James Webb Space Telescope spots the most distant galaxy ever seen (image)

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• James Webb Space Telescope spots 3 of our universe's earliest galaxies

The announcement of the discoveries, made in Oct. 2023 and Jan. 2024, are the latest developments in the ongoing investigation of cosmic dawn that the $10 billion telescope has facilitated as part of the JWST Advanced Deep Extragalactic Survey (JADES) program. JADES aims to provide vital insights into the ways in which the stars, gas, and black holes were evolving in primordial galaxies when the 13.8 billion-year-old universe was very young. 

"These galaxies join a small but growing population of galaxies from the first half billion years of cosmic history where we can really probe the stellar populations and the distinctive patterns of chemical elements within them," team member and Kavli Institute for Cosmology scientist Francesco D’Eugenio said in a statement.

JADES-GS-z14-0 isn't just remarkable for how distant it is from Earth and how early it existed in the cosmos, though. With a width of around 1,600 light-years across, this "cosmic dawn" galaxy is also remarkable for how big and bright it is.

"The size of the galaxy clearly proves that most of the light is being produced by large numbers of young stars, rather than material falling onto a supermassive black hole in the galaxy's center, which would [make it] appear much smaller, "JADES team leader Daniel Eisenstein from the Harvard & Smithsonian's Center for Astrophysics (CfA) said in a separate statement. 

The extreme brightness of JADES-GS-z14-0 and the fact this luminosity is powered by young stars means this galaxy represents the most striking evidence for the rapid formation of large, massive galaxies in the early universe found thus far.

JADES team member and University of California-Santa Cruz researcher Ben Johnson added that JADES-GS-z14-0 shows that galaxy formation in the early universe was very rapid and intense. 

"The JWST will allow us to find more of these galaxies, perhaps when the universe was even younger," he said. "It is a marvelous opportunity to study how galaxies get started."

The James Webb Space Telescope sees red to spot early galaxies

The JWST is adept at seeing early galaxies thanks to the high infrared sensitivity of its instruments, particularly its primary imager, the Near Infrared Camera (NIRCam). 

Light leaves these cosmic dawn galaxies with a wide range of wavelengths similar to light from galaxies that are closer to the Milky Way. It is the journey of billions of years that transforms this light into low-energy and long-wavelength light in the near-infrared and infrared regions of the electromagnetic spectrum.

The very fabric of space is expanding, and as light passes through it, its wavelength is stretched along with it. This causes the light to "shift" down to the red end of the electromagnetic spectrum, hence the name for this phenomenon, "redshift."

Galaxies that are farther away have to cross more space (which is being stretched as it expands) before their light reaches us, and thus, that light experiences more redshift. Redshift, denoted as z, can, therefore, be used to measure the distance to celestial objects with a known spectrum. And because light takes a finite amount of time to travel, this distance can be used to calculate how long ago these galaxies existed as we see them.

JADES-GS-z14-0 has a redshift of z = 14.32, while the previous most distant galaxy, JADES-GS-z13-0, has a redshift of z = 13.2, which placed it as existing 400 million years after the Big Bang. Clearly, this newly found galaxy has absolutely smashed that record, with the JWST seeing back in time by another 100 million years or so.

"JADES-GS-z14-0 now becomes the archetype of this phenomenon," JADES collaboration team member Stefano Carniani of the Scuola Normale Superiore said. "It is stunning that the universe can make such a galaxy in only 300 million years."

JADES-GS-z14-0 delived some surprises

Not everything about JADES-GS-z14-0 was immediately clear to the JADES team and some elements could confuse our picture of the early cosmos.

When it was first spotted, the primordial galaxy was so close to a closer foreground galaxy that the team suspected they could be celestial neighbors.  This idea was dispelled in October last year when the JADES crew spent five days performing a deep analysis of JADES-GS-z14-0 with NIRCam. The application of filters that are specifically tailored to identify early galaxies confirmed the extreme distance to JADES-GS-z14-0.

"We just couldn’t see any plausible way to explain this galaxy as being merely a neighbor of the more nearby galaxy," JADES team member and University of Arizona researcher Kevin Hainline said.

The galaxy also surprised its discoverers because its light is even redder than expected. That is because the light from JADES-GS-z14-0 is being "reddened" by dust within it that will become the building blocks of stars that will help this galaxy grow even larger.

Another surprise was the discovery of oxygen in JADES-GS-z14-0. Elements heavier than hydrogen and helium are forged by stars during their lifetimes and then distributed through galaxies when these stars explode. The observation of oxygen in JADES-GS-z14-0 could indicate that at least one generation of stars has already lived and died in this very early galaxy.

"All of these observations, together, tell us that JADES-GS-z14-0 is not like the types of galaxies that have been predicted by theoretical models and computer simulations to exist in the very early universe,"  JADES researcher Jake Helton of Steward Observatory and the University of Arizona said. "Given the observed brightness of the source, we can forecast how it might grow over cosmic time, and so far, we have not found any suitable analogs from the hundreds of other galaxies we’ve observed at high redshift in our survey."

Helton added that given the relatively small region of the sky that the JWST searched to find JADS-GS-z14-0, its discovery has profound implications for the predicted number of bright galaxies we see in the early universe.

"It is likely that astronomers will find many such luminous galaxies, possibly at even earlier times, over the next decade with the JWST," he concluded. "We're thrilled to see the extraordinary diversity of galaxies that existed at cosmic dawn!”

{ https://www.space.com/ }

31-05-2024 om 23:14 geschreven door peter  

Rare 'exo-Venus' with Earth-like temperature discovered

Gliese 12 b, which orbits a cool, red dwarf star located just 40 light-years away, promises to tell astronomers more about how planets close to their stars retain or lose their atmospheres. In this artist’s concept, Gliese 12 b is shown retaining a thin atmosphere.

Credit NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

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Astronomers have made the rare and tantalising discovery of an Earth-like exoplanet 40 light-years away that may be just a little warmer than our own world.

The potentially-habitable planet, named Gliese 12 b, orbits its host star every 12.8 days, is comparable in size to Venus - so slightly smaller than Earth - and has an estimated surface temperature of 42°C (107°F), which is lower than most of the 5,000-odd exoplanets confirmed so far.

That is assuming it has no atmosphere, however, which is the crucial next step to establishing if it is habitable.

It may have an Earth-like atmosphere, one more akin to Venus - which experienced a runaway greenhouse effect that made it a 400°C (752°F) hellhole - no atmosphere, or perhaps a different kind of atmosphere not found in our solar system.

Getting an answer is vital because it would reveal if Gliese 12 b can maintain temperatures suitable for liquid water - and possibly life - to exist on its surface, while also unlocking answers about how and why Earth and Venus evolved so differently.

Gliese 12 b is by no means the first Earth-like exoplanet to have been discovered, but as NASA has said, there are only a handful of worlds like it that warrant a closer look.

It has been billed as "the nearest, transiting, temperate, Earth-size world located to date" and a potential target for further investigation by the US space agency's £7.5billion James Webb Space Telescope.

The closest Earth-like exoplanet to us - and possibly the most famous - is Proxima Centauri b, which is only 4 light-years away. However, because it is not a transiting world we still have a lot to learn about it, including whether it has an atmosphere and the potential to harbour life.

Most exoplanets are discovered using the transit method, where a planet passes in front of its star from our point of view, causing a dip in the host star's brightness.

During a transit, the star's light also passes through an exoplanet's atmosphere and some wavelengths get absorbed. Different gas molecules absorb different colours, so the transit provides a set of chemical fingerprints that can be detected by telescopes like Webb.

Gliese 12 b’s estimated size may be as large as Earth or slightly smaller — comparable to Venus in our solar system. This artist’s concept compares Earth with different possible Gliese 12 b interpretations, from one with no atmosphere to one with a thick Venus-like one.

NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

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Attribution (CC BY 4.0)

Gliese 12 b could also be significant because it may help reveal whether the majority of stars in our Milky Way galaxy - i.e. cool stars - are capable of hosting temperate planets that have atmospheres and are therefore habitable.

The discovery of the 'exo-Venus', by two international teams of astronomers, has been published today in the Monthly Notices of the Royal Astronomical Society.

It orbits a cool red dwarf star called Gliese 12, which is almost 40 light-years away from Earth in the constellation Pisces.

"Gliese 12 b represents one of the best targets to study whether Earth-size planets orbiting cool stars can retain their atmospheres, a crucial step to advance our understanding of habitability on planets across our galaxy," said Shishir Dholakia, a doctoral student at the Centre for Astrophysics at the University of Southern Queensland in Australia.

He co-led a research team with Larissa Palethorpe, a doctoral student at the University of Edinburgh and University College London.

The exoplanet's host star is about 27 per cent of the size of our Sun and has a surface temperature that is around 60 per cent of our own star.

However, the distance separating Gliese 12 and the new planet is just 7 per cent of the distance between Earth and the Sun. Gliese 12 b therefore receives 1.6 times more energy from its star as Earth does from the Sun and about 85 per cent of what Venus experiences.

This difference in solar radiation is important because it means the planet's surface temperature is highly dependent on its atmospheric conditions. As a comparison to Gliese 12 b's estimated surface temperature of 42°C (107°F), Earth has an average surface temperature of 15°C (59°F).

"Atmospheres trap heat and - depending on the type - can change the actual surface temperature substantially," Dholakia explained. "We are quoting the planet's 'equilibrium temperature', which is the temperature the planet would be if it had no atmosphere.

"Much of the scientific value of this planet is to understand what kind of atmosphere it could have. Since Gliese 12 b gets in between the amount of light as Earth and Venus get from the Sun, it will be valuable for bridging the gap between these two planets in our solar system."

Palethorpe added: "It is thought that Earth's and Venus's first atmospheres were stripped away and then replenished by volcanic outgassing and bombardments from residual material in the solar system.

"The Earth is habitable, but Venus is not due to its complete loss of water. Because Gliese 12 b is between Earth and Venus in temperature, its atmosphere could teach us a lot about the habitability pathways planets take as they develop."

The closest Earth-like exoplanet to us - and possibly the most famous - is Proxima Centauri b (pictured in an artist's impression), which is only 4 light-years away. However, because it is not a transiting world we still have a lot to learn about it, including whether it has an atmosphere and the potential to harbour life.

NASA Visualization Technology Applications and Development (VTAD)

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Attribution (CC BY 4.0)

The researchers, along with another team in Tokyo, used observations by NASA's TESS (Transiting Exoplanet Survey Satellite) to help make their discovery.

"We've found the nearest, transiting, temperate, Earth-size world located to date," said Masayuki Kuzuhara, a project assistant professor at the Astrobiology Center in Tokyo, who co-led a research team with Akihiko Fukui, a project assistant professor at the University of Tokyo.

"Although we don't yet know whether it possesses an atmosphere, we've been thinking of it as an exo-Venus, with similar size and energy received from its star as our planetary neighbour in the solar system."

An important factor in retaining an atmosphere is the storminess of its star. Red dwarfs tend to be magnetically active, resulting in frequent, powerful X-ray flares.

However, analyses by both teams conclude that Gliese 12 shows no signs of such extreme behaviour, raising hopes that Gliese 12 b's atmosphere may still be intact.

"We know of only a handful of temperate planets similar to Earth that are both close enough to us and meet other criteria needed for this kind of study, called transmission spectroscopy, using current facilities," said Michael McElwain, a research astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and a co-author of the Kuzuhara and Fukui paper.

"To better understand the diversity of atmospheres and evolutionary outcomes for these planets, we need more examples like Gliese 12 b."

At 40 light-years from Earth, Gliese 12 b is about the same distance as the TRAPPIST-1 system.

This is made up of seven planets, all roughly in Earth's size range and likely rocky, orbiting a red dwarf star.

Three of these are in the habitable zone but at least two - and probably all of them - have no atmosphere and are likely barren, dismissing hopes when they were first discovered eight years ago that they could be water worlds hosting life.

• The new paper "Gliese 12 b, A Temperate Earth-sized Planet at 12 Parsecs Discovered with TESS and CHEOPS", Shishir Dholakia and Larissa Palethorpe et al., has been published in the Monthly Notices of the Royal Astronomical Society.

{ https://ras.ac.uk/ }

31-05-2024 om 20:54 geschreven door peter  

De planeet heeft een geschatte oppervlaktetemperatuur van slechts 42 graden Celsius en bevindt zich op ongeveer dezelfde afstand als het bekende TRAPPIST-1 systeem.

Al jaren speuren astronomen het universum af naar planeten die mogelijk leven kunnen ondersteunen of op zijn minst bewoonbaar zijn, in de hoop werelden te vinden die op de aarde lijken. En een nieuwe ontdekking heeft nu voor grote opwinding gezorgd. Op zo’n 40 lichtjaar afstand zijn onderzoekers namelijk op de veelbelovende planeet Gliese 12 b gestuit. Zou dit de planeet kunnen zijn waar we al zo lang naar op zoek zijn?

Gliese 12 b
De mogelijk bewoonbare planeet Gliese 12 b draait elke 12,8 dagen om zijn moederster. Qua grootte is de exoplaneet vergelijkbaar met Venus, wat betekent dat hij slechts iets kleiner is dan de aarde. Daarnaast heeft deze aardachtige planeet ook nog eens een aardachtige temperatuur. Zo wordt de oppervlaktetemperatuur geschat op 42 graden Celsius. Hiermee is hij iets warmer dan de aarde, maar opvallend koeler dan de meeste van de ongeveer 5.000 tot nu toe ontdekte exoplaneten. De ontdekking van deze ‘exo-Venus’, is vandaag gepubliceerd in de Monthly Notices of the Royal Astronomical Society.

Exo-Venus
Onderzoekers kwamen de veelbelovende planeet op het spoor met behulp van planetenjager TESS, die al heel wat exoplaneten aan het licht heeft gebracht. En onderzoekers zijn enthousiast. “We hebben de dichtstbijzijnde, gematigde wereld ter grootte van de aarde tot nu toe ontdekt,” benadrukt onderzoeker Masayuki Kuzuhara. “Hoewel we nog niet weten of Gliese 12 b een atmosfeer heeft, beschouwen we ‘m als een ‘exo-Venus’. Het heeft een vergelijkbare grootte en ontvangt een vergelijkbare hoeveelheid energie van zijn ster als onze buurplaneet in ons eigen zonnestelsel.”

Atmosfeer
Om er echter zeker van te zijn dat de planeet leefbaar is, is het van cruciaal belang om te bepalen of er wel of geen atmosfeer aanwezig is. Het is mogelijk dat de planeet een atmosfeer heeft die vergelijkbaar is met die van de aarde. Deze kan echter ook meer lijken op die van Venus, waar een omvangrijk broeikaseffect ervoor zorgde dat het oppervlak een verzengende 400 graden Celsius bereikte. Een andere mogelijkheid is dat de planeet geen atmosfeer heeft. Of misschien heeft ie wel een soort atmosfeer die we nog niet in ons eigen zonnestelsel hebben gezien. Het is erg belangrijk om hierop een antwoord te krijgen omdat het ons zal vertellen of Gliese 12 b temperaturen kan handhaven die geschikt zijn voor vloeibaar water – en mogelijk leven – op het oppervlak.

Moederster
Om dit te achterhalen, is ook de moederster relevant. De moederster van Gliese 12 b is een koele rode dwergster genaamd Gliese 12, die zich zoals gezegd op bijna 40 lichtjaar afstand van de aarde bevindt, in het sterrenbeeld Vissen. De ster is ongeveer 27 procent zo groot als onze zon en heeft een oppervlaktetemperatuur van ongeveer 60 procent van die van onze zon. Over rode dwergsterren is echter bekend dat het ‘opvliegende’ sterren zijn, die vaak magnetisch actief zijn. Dit resulteert in frequente, krachtige uitbarstingen, waardoor een mogelijk rondom cirkelende planeet van zijn atmosfeer wordt ontdaan. Toch lijkt Gliese 12 b er beter vanaf te komen. Analyses hebben namelijk aangetoond dat Gliese 12 geen tekenen vertoont van dergelijk extreem gedrag. Dit verhoogt de hoop dat de potentiële atmosfeer van Gliese 12 b nog steeds intact is.

Oppervlaktetemperatuur

Daarnaast is de afstand tussen Gliese 12 en de nieuw ontdekte planeet slechts 7 procent van de afstand tussen de aarde en de zon. Hierdoor ontvangt Gliese 12 b 1,6 keer meer energie van zijn ster dan de aarde van de zon, en ongeveer 85 procent van de hoeveelheid die Venus ontvangt. Dit verschil in de hoeveelheid zonnestraling die de planeet ontvangt, is van groot belang omdat het aangeeft dat de oppervlaktetemperatuur sterk wordt beïnvloed door de atmosferische omstandigheden. Voor je beeldvorming: de geschatte oppervlaktetemperatuur van Gliese 12 b is 42 graden Celsius, terwijl de gemiddelde oppervlaktetemperatuur van de aarde 15 graden Celsius bedraagt. “Atmosferen houden warmte vast en kunnen, afhankelijk van hun samenstelling, de werkelijke oppervlaktetemperatuur aanzienlijk beïnvloeden,” legt onderzoeker Shishir Dholakia uit.

Aarde en Venus
Het onderzoek naar Gliese 12 b heeft overigens niet alleen betrekking op de leefbaarheid van deze planeet. Het helpt ons ook om meer te weten te komen over waarom de aarde en Venus, die in veel opzichten erg op elkaar lijken, toch zo’n andere weg zijn ingeslagen. “Omdat Gliese 12 b een vergelijkbare hoeveelheid licht ontvangt als de aarde en Venus van de zon, kan het ons ook helpen om het verschil tussen deze twee planeten in ons eigen zonnestelsel te verklaren en te begrijpen,” aldus Dholakia. Dit kan waardevolle inzichten bieden in de atmosferische processen die de leefbaarheid van planeten beïnvloeden. Terwijl de aarde bewoonbaar is, is Venus dat niet, voornamelijk vanwege het volledige verlies van water. “Gliese 12 b, met een temperatuur tussen die van de aarde en Venus in, kan ons helpen begrijpen hoe planeten bewoonbaar worden, vooral door te kijken naar welke atmosfeer het heeft,” vertelt mede-auteur Larissa Palethorpe.

Onderzoek naar de veelbelovende exo-Venus gaat onverminderd door. Want het idee dat deze planeet mogelijk leefbaar is, prikkelt de verbeelding van menig astronoom. Gliese 12 b is zeker niet de eerste aardachtige exoplaneet die is ontdekt, maar volgens NASA zijn er maar een paar van zulke werelden die de moeite van nader onderzoek waard zijn. De volgende stap is om de krachtige ruimtetelescoop James Webb op Gliese 12 b te richten. Uiteindelijk hopen onderzoekers te achterhalen of deze planeet al dan geen atmosfeer herbergt. “Gliese 12 b vertegenwoordigt een van de beste doelen om te bestuderen of aardachtige planeten die om koele sterren draaien hun atmosferen kunnen behouden,” zegt Dholakia. “Dit is een cruciale stap om ons begrip van de bewoonbaarheid van planeten in ons sterrenstelsel te bevorderen.”

Bronmateriaal

• "Rare 'exo-Venus' with Earth-like temperature discovered" - Royal Astronomical Society.
  
• Afbeelding bovenaan dit artikel: NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

{ https://scientias.nl/ }

31-05-2024 om 20:41 geschreven door peter  

Nanoplastics nu ook op onverwachte plek in hart van foetus teruggevonden. En de kans is groot dat dat schadelijk is

Jeannette Kras

 

{ https://scientias.nl/ }

31-05-2024 om 20:22 geschreven door peter  

The breakthrough relied on the combination of annual growth ring measurements with the measurable spike in cosmogenic radiocarbon that occurred during the 5259 BC event. This allowed them to establish a chronological reference point for producing accurate dates for the historic settlement, which now may significantly aid archaeological dating at other sites in Southeast Europe.

Additionally, the team behind the new findings says their methods could mark a new standard for dating ancient sites through such processes.

AN EXTREME COSMIC EVENT IN ANCIENT TIMES

In 2022, researchers discovered a pair of extreme solar energetic particle (SEP) events by employing carbon isotope measurements in ancient tree rings dated to 7176 and 5259 BC. Each of the events yielded an increase in 14C of about 2%, a relatively small percentage, albeit one indicating events of far greater magnitude than all similar events previously observed.

Such occurrences happen periodically during eruptive events such as flares and coronal mass ejections, the most recent of which bombarded the planet with cosmogenic radiation beginning on May 10, 2024, producing visible aurorae in parts of the world where such colorful light displays are rarely seen.

Since the observational record is too short to provide an accurate estimation of the frequency of extremely rare SEP events, scientists look for the presence of radionuclides like 10Be, 14C, and 36Cl, all of which can be produced when cosmic rays strike Earth’s atmosphere—to help them reconstruct a clearer picture of past solar activity and highly energetic events like the one that occurred in 5259 BC.

STORIES TOLD IN TREE RINGS

Dendrochronology, the process of using annual growth discernible in tree rings to help date events from the past, is useful for more than just determining things like when extreme solar events have occurred: archaeologists also use it to help them reveal the ages of ancient artifacts and archaeological features that include tombs and settlements.

Above: Cross-section of a California Coast Redwood tree felled in 1934, with rings labeled to indicate several historical events that occurred between 1215 to 1620 AD

(Credit: Larry McElhiney/CC 2.5)

Now, a team from the University of Bern, led by the Institute of Archaeological Sciences, was successfully able to produce dates for the ancient site of Dispilio in northern Greece, using evidence of high-energy particles revealed in timber discovered at the site.

Previous attempts to date the site had proven difficult for a variety of reasons, which include the fact that while tree-ring data extending further back than 12,500 years is readily attainable in many parts of Europe, the same is rarely true for the Mediterranean, according to Andrej Maczkowski, lead author of a study outlining the University of Bern team’s findings.

In fact, there are only a handful of regions around the world where the presence of continuous tree-ring chronologies allows dating accuracy down to the year, such as parts of the American Southwest and northern Alpine foothills and parts of the British Isles. Because of this, dendrochronological dating methods have traditionally been limited.

MIYAKE EVENTS: A PARADIGM SHIFT IN DATING THE PAST

That is, until 2012, when a breakthrough made by Japanese physicist Fusa Miyake revealed that cosmic rays originating from solar flares resulted in spikes in radionuclides, specifically the presence of 14C content found in tree rings.

Now known as Miyake events, dendrochronological data related to these occurrences offer researchers a powerful tool in the form of global anchor points for dating under conditions where annual growth ring chronologies are normally absent. Scientists have now charted Miyake events as far back as 12,350 BC.

“Miyake’s discovery was a paradigm shift,” said Albert Hafner, a University of Bern Professor of Prehistoric Archaeology and senior author of the team’s new study.

Now, Hafner and his colleagues say the area has become “the first region to benefit from this paradigm shift, allowing for absolute dating independent of a consistent calendar.” This is a significant point given that the Balkans are home to many of Europe’s earliest settlements, many of which existed along ancient lakes and other bodies of water around or just after 6000 BC. These thriving ancient communities played a key role in the spread of agriculture throughout the rest of the continent during the ensuing thousands of years.

PRECISION DATING OF AN ANCIENT GREEK SETTLEMENT

In their recent research, the Bern team was able to define a growth ring chronology spanning more than 300 years that ends in 5140 BC, which they achieved by analyzing 787 timber samples collected at Dispilio. With knowledge of the Miyake event that occurred in 5259 BC, the team was able to determine very precise dating that aligned with existing global tree-ring chronologies.

Above: An assemblage of adornments and other artifacts dating to the Neolithic period, recovered during excavations at Dispilio

(Credit: Dispilio Excavation Archive).

Of key significance, the Bern team’s research greatly advances our understanding of prehistoric timelines, offering crucial information for archaeologists and historians about the spread of early farming communities throughout Europe.

“We expect other regional chronologies to rapidly link to the ‘Dispilio Chronology,’” Maczkowski said, “paving the way for a comprehensive dendrochronology for the southern Balkans.”

Maczkowski, Hafner, and the team’s new paper, “Absolute dating of the European Neolithic using the 5259 BC rapid 14C excursion,” was recently published in the journal Nature Communications.

• Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.

{ https://thedebrief.org/category/space/ }

31-05-2024 om 01:16 geschreven door peter  

New Data Reveals How Galaxies Grew in the Early Universe

These new galaxies in the early universe were still hungrily gobbling up nearby gas.

BY KIONA SMITH

 

University of Copenhagen astrophysicist Kasper Heintz and his colleagues published their work in the journal Science.

THE EPOCH OF REIONIZATION IS GONNA BE LIT

JWST’s instruments helpfully split the light from the distant galaxies into the individual wavelengths that make it up. The spectrum of light coming from an object, like a galaxy, is like a fingerprint of the chemicals that form it, because each chemical compound absorbs, emits, and reflects its own very specific wavelengths of light. Around the three distant galaxies, Heintz and his colleagues noticed that something seemed to be absorbing the same wavelengths of light as cold hydrogen gas – and lots of it.

“These galaxies are like sparkling islands in a sea of otherwise neutral, opaque gas,” says Heintz in a recent statement.

Hydrogen gas, when it’s cold and not electrically-charged (or ionized), absorbs light but doesn’t emit it. This neutral gas filled the early universe, making it impossible for light to travel very far, until a few hundred million years after the Big Bang: a period called the Cosmic Dark Ages.

It took powerful blasts of radiation from the first stars in the first galaxies to strip away electrons from all those hydrogen atoms, creating ionized gas (also called plasma) which is translucent instead of opaque. The Epoch of Reionization had begun – and the three galaxies in Heintz and his colleagues’ recent study are just starting to light it up.

BRAND NEW GALAXIES, SOME ASSEMBLY REQUIRED

Somewhere between 13.2 billion and 13.4 billion years ago — when the light that just reached JWST started its long journey across space — these three early galaxies were still in the process of assembling themselves from the surrounding gas.

“[The data] suggests that we are seeing the assembly of neutral hydrogen into galaxies,” says University of Copenhagen astrophysicist Darach Watson, a coauthor of the recent study, in a statement. And that’s a stage of galaxy formation that astronomers haven’t seen before, especially in the very early universe.

The galaxies, in their infancy, are still surrounded by a cloud of cold, dark, neutral hydrogen gas — the same stuff that caused the Cosmic Dark Ages. Most of that gas will be heated up as it falls into the galaxies, pulled in by their inexorable gravity. And then it will slowly cool, forming lumps like congealed oatmeal, and some of those lumps will be so heavy that they collapse on themselves to form new stars.

Right now (or as we see them right now, which actually happened billions of years ago), what stars these early galaxies contain are mostly young and newly-formed.

“The fact that we are seeing large gas reservoirs also suggests that the galaxies have not had enough time to form most of their stars yet.” But they’ll get there, most likely.

The data reveals not only a previously unseen moment in a galaxy’s life, but also a glimpse of what the early universe was like before the expansion of space pulled everything farther apart, turning most galaxies into lonely beacons, or at most isolated clusters of lights, in the void.

“We’re moving away from a picture of galaxies as isolated ecosystems,” says University of Copenhagen astrophysicist Simone Nielsen in a recent statement. “At this stage in the history of the universe, galaxies are all intimately connected to the intergalactic medium with its filaments and structures of pristine gas.”

In the very early universe, no galaxy was an island (yet).

 { https://www.inverse.com/ }

31-05-2024 om 00:20 geschreven door peter  

By Shanna Hogan

Sarah2/Shutterstock

As related in a 1950 book called "Behind the Flying Saucers," the tale features two men who pulled a couple of dead alien corpses from the wreckage and stored them in a freezer until the army picked them up. Another version has the spacecraft crashing miles away, in Cave Creek or Paradise Valley.

"What’s amazing and significant is that there were two UFO crashes, one in Roswell and one in Phoenix, within fairly close proximity, that occurred in the same year," Willes says. "As far as the dam being built over the crash site, that’s a possibility, but I don’t see why the government wouldn't just remove the wreckage and there wouldn't be anything left but desert landscape."

A 1945 U.S. government Phoenix Sectional Chart showing Marana Army Air Field and Marana Auxiliary Army Airfield No. 2, No. 4, No. 5

Chris Kennedy/Public domain

A screengrab of camcorder footage of the V-shaped formation of lights that appeared over the Valley on March 13, 1997.

Screen Grab

5. The Phoenix Lights (1997)

As most Arizonans know, the otherworldly event that elevated Phoenix's prominence in the annals of UFO lore was the Phoenix Lights — one of the largest mass UFO sightings of all time.

On March 13, 1997, a string of glowing orbs hovered over Paradise Valley skies. For three hours the huge, V-shaped formation passed silently over a 300-mile corridor from the Nevada line through Phoenix to the northern edge of Tucson.

The lights were witnessed by thousands and photographed by hundreds, who had been watching the skies that night to catch a glimpse of a passing comet.

"Much has happened since the historic and still-unexplained March 13, 1997, mass sighting, propelling the Phoenix Lights into the international limelight as the most witnessed, most documented, and most important mass anomalous aerial events in modern history,” she tells New Times. 

Jeff Willes says the Phoenix Lights was impossible for the government to conceal. 

"The Phoenix Lights is Arizona's biggest UFO story," he says. "Thousands of witnesses saw this V-shaped object that flew all across the state. There still hasn’t been a UFO sighting like that in UFO history."

    - (This article originally appeared in 2016 and has been updated.)

30-05-2024 om 22:13 geschreven door peter  

Webb-telescoop legt melkwegstelsel vast van 290 miljoen jaar na oerknal

Wetenschappers hebben, met behulp van de James Webb-ruimtetelescoop (JWST), een melkwegstelsel gevonden dat "slechts" 290 miljoen jaar na de oerknal bestond. Dat meldt het Europese ruimtevaartagentschap ESA, dat spreekt van een record, donderdag.

De afgelopen twee jaar hebben wetenschappers de telescoop gebruikt om de zogenaamde Cosmic Dawn, of kosmische dageraad, te onderzoeken, de periode in de eerste paar honderd miljoen jaar na de oerknal waarin de eerste sterrenstelsels ontstonden. "Die sterrenstelsels geven vitaal inzicht in de manieren waarop het gas, de sterren en de zwarte gaten veranderden toen het heelal nog heel jong was", aldus ESA.

In oktober 2023 en januari 2024 gebruikte een internationaal team van astronomen de ruimtetelescoop om sterrenstelsels te observeren als onderdeel van het JWST Advanced Deep Extragalactic Survey (JADES) programma. Het gaat om een observatieprogramma dat zich, gebruikmakend van Webb's NIRSpec (Near-Infrared Spectrograph), focust op een heel klein deel van de hemel en die focus behoudt voor langere tijd. Het resultaat zijn zogenaamde deep field-beelden van verafgelegen hemellichamen.

"Wetenschappers hebben op die manier een melkwegstelsel ontdekt dat slechts 290 miljoen jaar na de oerknal werd waargenomen", zo klinkt het.

De Webb-telescoop, de opvolger van de beroemde ruimtetelescoop Hubble, is ontwikkeld door de Verenigde Staten, Europa en Canada. Hij werd in 2021 gelanceerd.

Ter info: de oerknal, of Big Bang, zou zo'n 13,7 miljard jaar geleden hebben plaatsgevonden.

{ https://www.msn.com/nl-be/feed?ocid=msedgntp&pc=acts }

30-05-2024 om 20:31 geschreven door peter  

The Meteor’s Appearance

To most observers, the meteor over Portugal and Spain looked blue-green and very bright. Those colors are created as various elements in the meteor get heated up by friction with our atmosphere. That vaporizes them and we see the “fiery” aspect light up the sky. If it was a piece of a comet, then the colors also indicate the materials it contained. Most comets contain water, carbon dioxide, ammonia, and methane ice. Other comet “stuff” consists of silica dust, carbon, various metals, and organic molecules. The metals, in particular, could show spectacular colors as they heat up and vaporize.

It’s not known which comet supplied the chunk that broke up and vaporized that night. Earth’s orbit crosses the orbit of several different comets. As they travel through space, particularly as they get close to the Sun, comets shed pieces of themselves. That cometary debris stays in the original orbit around the Sun. Occasionally, Earth’s orbit intersects that cometary path. Its particles particles eventually end up in our atmosphere. The best-known path creates the Orionid Meteor Shower and we can thank Comet Halley for that show from late September to mid-November.

Surveys to Detect an Incoming Space Rock

As planetary scientists learn more about the near-Earth environment and its population of asteroids and other space debris, they’ve formed observation groups within NASA and ESA. There’s a network of ground-based observers and facilities that watch the sky each night, looking for incoming impactors. Most of the time, their search is limited to objects larger than the Portugal/Spain object. In addition, satellites such as MeteoSat can pick up these intruders. MeteoSat was launched by ESA to monitor weather conditions and detect lightning strikes. The instrument has four cameras covering Europe, Africa, the Middle East, and parts of South America. Each can capture up to a thousand images per second, allowing the satellite to monitor lightning continuously from space.

ESA’s Planetary Defence Office is in charge of monitoring the positions and approaches of near-Earth objects that could pose a threat to any portion of our planet. It does regular observing campaigns to search for bits of asteroids and comets. NASA operates the Center for Near Earth Object Studies (CNEOS) to do similar searches for possibly dangerous rocks. The Near-Earth objects it’s most concerned about are asteroids and comets with orbits that bring them to within 195 million kilometers of the Sun. Their orbits can move through our planet’s neighborhood. Most of these small bodies are asteroids as small as a few meters wide to nearly 40 kilometers across.

The office uses data from observatories around the world—both professional and amateur. Much of this data comes from larger facilities, including Pan-STARRS, the Catalina Sky Survey, and NASA’s NEOWISE mission. In addition, there’s a significant program of planetary radar measurements that contribute data to the NEO observations effort. All of these skywatching campaigns contribute to increased awareness and predictions of near-Earth objects that could pose a threat to our planet.

For More Information

• Fireball Witnessed by Weather Satellite
• Asteroid Watch
• ESA Planetary Defence Office

{ https://www.universetoday.com/ }

30-05-2024 om 00:41 geschreven door peter  

“Euclid is a unique, ground-breaking mission, and these are the first datasets to be made public – it’s an important milestone,” says Valeria Pettorino, ESA’s Euclid Project Scientist. “The images and associated science findings are impressively diverse in terms of the objects and distances observed. They include a variety of science applications, and yet represent a mere 24 hours of observations. They give just a hint of what Euclid can do. We are looking forward to six more years of data to come!”

The leading image is the most stunning and perhaps the most relatable. It shows Messier 78, aka NGC 2068. It’s a reflection nebula and star-forming region contained in the vast Orion B molecular cloud complex. Euclid used its infrared capabilities to see through the dust that shrouds the star-formation region. It’s given us our most detailed look at the filaments of gas and dust that give the region its ghostly appearance.

Euclid can detect objects that are just a few times more massive than Jupiter, an impressive feat. In its M78 image, it found over 300,000 objects in that mass range.

One of Euclid’s objectives is to study dark matter and how it’s distributed in the Universe. It uses gravitational lensing to probe dark matter, and its image of the Abell 2390 galaxy cluster exhibits the tell-tale curved arcs of light coming from distant background objects created by gravitational lensing. The image also shows more than 50,000 galaxies.

Most of the stars currently forming in the Universe are forming in spiral galaxies. Euclid captured this image of NGC 6744 as an archetype of that galaxy type. The telescope’s wide-angle lens and depth of field capture the entire galaxy and also small details. It shows lanes of dust that emerge as spurs on the spiral arms.

With this image, astronomers can map individual stars and the gas that feeds their formation. They can also identify globular clusters and new dwarf galaxies. Euclid already found one new dwarf galaxy astronomers have never seen before, which is impressive for a galaxy that’s already been studied so intently.

Euclid also imaged another galaxy cluster, Abell 2764. This cluster contains hundreds of galaxies within a halo of dark matter. Euclid’s impressive wide-field view comes into play in this image. Not only does it show Abell 2764 in the image’s upper right, but it also shows other clusters that are even more distant, multiple background galaxies, and interacting galaxies with their streams of stars.

The image highlights one of Euclid’s other capabilities. The foreground star is in our own galaxy, and when viewed with a telescope, its diffuse light creates a halo that obscures distant objects behind it. Euclid was built to minimize that diffuse halo effect. The disturbance from the star’s diffuse light is minimal, meaning Euclid can see distant background objects near the star’s line of sight.

The final of the five new images is of galaxies in the Dorado Group. Euclid’s image shows signs of galaxies merging. The Dorado Group is a relatively young group, and many of its member galaxies are still forming stars. The image helps astronomers study how galaxies form and evolve inside halos of dark matter.

A zoomed-in image shows more detail of the main pair of galaxies in the image. Euclid’s unique large field-of-view and high spatial resolution means that for the first time, astronomers can use the same instrument and observations to deeply study tiny objects the size of star clusters, intermediate objects like the central regions of galaxies, and larger features like tidal tails in one large region of the sky.

Prior to Euclid, astronomers had to use small chunks of data to painstakingly catalogue globular clusters around galaxies. But Euclid’s wide images capture far more data in a single image, simplifying the task. Globular clusters provide important clues to how galaxies evolve over time.

Euclid’s mission is only starting. The telescope’s images so far have no equivalent, and there’s much more to come. Euclid hasn’t even begun its main survey yet. That survey will comprise both a wide survey covering about 15,000 square degrees of the sky and a deep survey covering about 50 square degrees.

“It’s no exaggeration to say that the results we’re seeing from Euclid are unprecedented,” says ESA Director of Science, Prof. Carole Mundell. “Euclid’s first images, published in November, clearly illustrated the telescope’s vast potential to explore the dark Universe, and this second batch is no different.”

“The beauty of Euclid is that it covers large regions of the sky in great detail and depth, and can capture a wide range of different objects all in the same image – from faint to bright, from distant to nearby, from the most massive of galaxy clusters to small planets,” said Mundell. “We get both a very detailed and very wide view all at once. This amazing versatility has resulted in numerous new science results that, when combined with the results from Euclid’s surveying over the coming years, will significantly alter our understanding of the Universe.”

• The scientific papers released with these images are available here.

{ https://www.universetoday.com/ }

30-05-2024 om 00:24 geschreven door peter  

Pour one out for NASA’s large flying laboratory, an old and hardworking DC-8 aircraft that the space and aeronautics agency just retired. The plane came into the world in 1969, the same year that NASA astronauts first walked on the moon during the Apollo era. The agency converted it to be a flying lab after buying the aircraft from Alitalia in 1985 and started using it for missions in 1987, during the space shuttle era. Its final resting place is at Idaho State University, where it will serve as a ground-based training aircraft for mechanics.

But life, and science, keep cruising onward: The plane’s successor is an even bigger aircraft, a modern Boeing 777 that will become NASA’s next flying laboratory. It’s due to start conducting science flights late next year.

“The DC-8 is a special plane,” says Nicki Reid, the aircraft’s operations engineer. “It’s accomplished a lot in its life.” That may be an understatement. There are big shoes to fill to replace what NASA has dubbed “the largest flying science laboratory in the world.”

NASA’S JACK OF ALL TRADES

NASA’s retiring DC-8 carried out many different types of scientific research while airborne. It could fly for as long as 10 or even 12 hours, although Reid says a standard mission would last between six and 10 hours. The flying lab, she says, could hold dozens of instruments — the exact equipment could change based on the mission — and as many as 55 people.

Those instruments were surprisingly versatile. One of the most straightforward things the plane studied was the air it was flying through. Its most recent mission had it measuring air quality in Asia, for example, and it also trailed a Boeing 737 to study its contrails.

It also had a key role in larger scale science. Historically, and probably most famously, it played a key role in studying the recovery of the hole in the ozone layer, a problem that the United Nations said in 2023 was thankfully moving in the right direction after the global ban on ozone-depleting substances. Turning from atmosphere to the ground, from 2009 to 2019, the aircraft studied the thickness of ice in Antarctica as part of a mission called Operation IceBridge.

The plane also acted as a test bed for satellite instruments before they were launched into space. And after they were, it could check to see if they were staying in working order, validating how satellite instruments were doing once they were in space by flying under the satellite’s path, and taking its own measurements, thus allowing researchers to compare those with what the satellite saw.

Using an aircraft to carry out research allows scientists to get an important viewpoint. “We go out and do things on aircraft that we can’t do with satellites or ground-based measurement,” says Amin Nehrir, a research scientist with NASA. We “look at processes in the atmosphere and the surface that are on short-enough time scales that we can’t see them from space — because from space, we sample them once a day, or maybe once every 16 days — and from the ground, we only have one data point in one location. And so the aircraft allows us to bridge these spatial and temporal scales.”

Nehrir highlights one particular instrument on the aircraft: an ozone lidar called DIAL, which employs lasers to measure what’s going on with the air outside the plane. It “was integral to finding the ozone hole,” he says.

TIME FOR RETIREMENT

Operating an old plane like the DC-8 — a four-engine type of passenger aircraft that Delta Air Lines, for example, flew between 1959 and 1989 — came with a cost. “It was getting hard to maintain,” says Reid. “We had to buy our tires custom-made, we had to buy brakes custom-made, and those get expensive when you’re a customer of one.”

Besides that, on board the DC-8, the climate situation wasn’t exactly perfectly temperature controlled. “It’s rarely a pleasant flight,” Reid says. And it was loud, too. “We took out a lot of the insulation, so that we could have access to a lot of the wiring running through the walls, so we can hear the engine noise quite a bit,” she says. Noise-canceling headphones with a built-in communications system helped with that issue.

The old-school nature of the aircraft compels Carrie Worth, a NASA Gulfstream pilot who has also flown the DC-8, to compare it to a “dump truck with wings.” That’s because it was a very hands-on aircraft to fly and had little automation, the equivalent of an older car that requires you to manually roll up or down the windows instead of pushing a button.

WHAT’S NEXT

The new aircraft is a Boeing 777 that, like the DC-8, used to be a passenger airliner. A widebody plane with two engines built in 2003, this 777 was owned by Japan Airlines before NASA bought it. Right now, the aircraft is having work done on it in Louisiana.

Its mission, says Glenn Jamison, who directs the Research Services Directorate at NASA, will be “understanding our Earth.”

As a successor to the DC-8, the new aircraft “brings a significant increase in the capacity,” Jamison says. “It also brings a significant increase in reach and endurance.” That means it can go farther and stay in the air for longer — as long as 18 hours.

This is one factor that’s important for doing science. “How long can you stay over an area and take measurements that are not broken by having to return to base?” says Jamison. That’s why an aircraft that can stay in the air for a long time is useful for scientists. It is being designed to be able to carry some 100 researchers, he says. And students may be able to fly on it someday, through a program called SARP.

NASA does have other research aircraft at its disposal, such as Gulfstream jets, a P-3 Orion, and two ER-2s, which are similar to the Air Force’s U-2 aircraft and can soar as high as 70,000 feet.

But the DC-8’s end of life comes, as The New York Times reports, as a trio of important NASA satellites — Terra, Aqua, and Aura — are nearing the end of their lifetimes, too. Satellites and research aircraft work well together, because the aircraft can essentially check the satellite’s work.

“The aircraft will never be able to pick up the slack from a satellite — because the satellite is 24/7, it’s global,” says Nehrir. When NASA loses satellites, he says, another aspect that gets lost is the way the plane works with them. “We typically go do these science investigations within the context of the satellite measurements — so we place the aircraft under the satellite, so that we can understand how to better interpret the satellite measurements, how to calibrate and validate them, and so we lose that component once the satellites turn off.”

In regard to the sunsetting of the three satellites, a NASA representative says that other existing instruments, such as SAGE on the International Space Station and a Canadian instrument on a Swedish satellite, can study the atmosphere and that they’re also looking into a proposal called STRIVE. Among other tasks, STRIVE would focus on studying the state of the ozone layer.

Whatever the future may hold, there’s no doubt that one 55-year-old DC-8 has done its part for science as the little flying laboratory that could.

{ https://www.inverse.com/ }

29-05-2024 om 21:07 geschreven door peter  

Arizona Man Filmed Huge Solid UFO In Phoenix Lights: MIB Took Video & Man Vanished

On the night of March 13, 1997, the people of the United States witnessed one of the largest and best-known UFO sightings in history. The UAP phenomenon was observed in the skies over the southwestern states of Arizona and Nevada and the Mexican state of Sonora. According to a Rocky Mountain Poll conducted at the time, as well as the commotion that ensued, around 10% of Arizonans claimed to have witnessed the incident that is now known as “The  Phoenix Lights.”

One of the eyewitnesses named Richard Curtis from Arizona, claiming to have solid evidence of the incident, contacted local Councilwoman Frances Barwood. He vanished following an encounter with  MIB and a media revelation.

Frances Barwood, a member of the city council, opened an investigation into the incident. Since the military and local authorities had already managed to claim that the lights seen by the eyewitnesses were only flares, her coworkers thought her behavior was ludicrous.

Barwood received a call from Richard Curtis a few months later. He said right away that he had extremely detailed footage of the  Phoenix Lights despite being an injured former soldier. He claimed that had personally captured them using high-quality equipment.

“He said you could see the shape. He said you could see how big it was in comparison to the surrounding buildings and everything. He described that the lights were gaseous. He was so excited that he had gotten all this on video,” Barwood recalled him telling her. Additionally, Curtis admitted to Barwood that he had no idea who else to call and that he trusted her.

Since the majority of the  Phoenix Lights video footage up until this point had been merely specks of light on a dark background, Barwood was intrigued by this message. Curtis agreed to provide copies of the footage to Barwood’s office after she urged him to do so. However, days passed, and she did not receive films either by mail or by courier. “I thought he made this up. He didn’t have video, you know, all this stuff,” she said.

A week later, Curtis telephoned Barwood at her house and inquired about her thoughts on the films. Barwood informed him that she had not received them and expressed her amazement. Curtis continued by telling her that following their phone call, two men from her workplace stopped up at his home. The two “similar-looking” individuals were fully covered in black (three-piece black suits, black shoes, black hats, black suitcases, etc.). The men were not dressed in jackets or other gear, even though it was fairly chilly outside. It struck Curtis as weird.

He asked the men if they were from Barwood’s office and they confirmed it. Then they inquired about the  Phoenix Lights videos, specifically to find out if Curtis had copied them. They responded that they would make copies for him themselves when he said he had not been able to. Curtis then handed them his videos and the two men left his house in a black sedan.

Barwood informed Curtis that she had no men in her office and that all of her staff were female. “I had no idea who these guys were. It sounds so bizarre. Nothing made sense to me,” Barwood recalled thinking. All of this infuriated Richard Curtis, who concluded that the authorities had misled him. In an interview with  Phoenix TV, he discussed everything that had happened, including the “Men in Black” visit and that they took his videos.

Read also:

• Neil Armstrong Confided Italian Journalist That UFOs Observed Them Insistently On Moon
• Harvard Scientist Explains Which UFOs Over Ukraine Could Be Extraterrestrial Spacecraft
• Ex-US Army Major Released NASA Footage Of 2000-Mile-Long UFO Near Saturn
• Ex-CIA Officer: Truth About UFOs Is Terrifying & Interdimensional Beings Are Within Us

And shortly after that, when Barwood tried to call Curtis, she discovered that he was not answering. When she got to his apartment, he was not there, but the neighbors informed her that Curtis had supposedly taken a faulty medication and had been transported by ambulance to the hospital. There were no records of Curtis ever being admitted to any Phoenix-area hospitals when Barwood started looking for him there.

Barwood made the decision to have her phone lines checked by a professional when she questioned how the odd men even knew about the tapes. He visited her house and conducted his tests there. After that, he went outdoors. “He wouldn’t come back in the house. He came to the backdoor and said, “No, I’m not coming in. Yes, your phone is tapped, it’s a government tap,” she said.

Since the military and authorities insisted that the  Phoenix Lights were nothing more than flares, Barwood was astounded to learn that someone in the US government had tapped her phones. Richard Curtis vanished without a trace.

It became a worldwide sensation throughout the course of the subsequent months. It was “the second biggest case in UFOlogy after  Roswell,” according to the late Art Bell, host of the syndicated paranormal radio program Coast to Coast AM.

The bizarre light show, according to skeptics, was caused by man-made aircraft from Glendale’s Luke Air Force Base or other neighboring military installations conducting training drills. The  Phoenix Lights, according to UFOlogists, were not of this world.

Below you can find a transcript from a FOX10 NEWS ( Phoenix Lights) reported by Jim Schnabel: (Source)

Voiceover: Months after this (March 13) sighting there are many questions regarding the strange lights over Phoenix. Is this a solid craft, or merely lights in an empty sky? What could be the conclusive evidence is now mysteriously missing. Richard Curtis claims his home video is proof that this sighting was a huge flying craft. And he claims his video shows a solid object in the sky passing over his home.

Curtis: I saw the bottom part (of the craft) as it went over  Phoenix, because the lights lit the bottom of it, and it partially blocked out the clouds and the stars. : voiceover: Curtis called city councilwoman Frances Emma Barwood, wanting to show her the footage. : (on screen: cut to a headshot of Barwood)

Barwood: He said he had it on two videotapes, and would I like them, so I said, “Of course I would.”, and could he give me copies of them. He said he would. I told him how to get them to my office and to mark them ‘personal and confidential’.

Voiceover: But before Curtis could send copies to Barwood, he’s paid a visit by two mysterious men in black. : Curtis:(voiced over  MIB reenactments) They were dressed in black suits, with black hats and sunglasses. They asked me if I had tapes for councilwoman Barwood, and I said “Yah, they’re laying right here”. They said, “We’ve stopped by to pick them up.” So I said, “Great!” and just handed (the original tapes) to them.

Barwood: I didn’t get them, and I have no idea who these two men were since I have just females working in my office. It’s absolutely puzzling to me.

Voiceover: Did the tapes ever exist, and if so were they proof of more than “lights” in the sky? And who were these mysterious  Men in Black who allegedly took them?

Curtis (voiced over): I think someone listened in on that phone call and wanted those tapes.

Barwood (voiced over): I can’t explain it. It’s just eerie. Voiceover: The mystery continues.

• Source: Encounter: UFO, Season 1, Episode 5, Episode aired Sep 21, 2021

{ https://www.howandwhys.com/ }

29-05-2024 om 01:31 geschreven door peter  

Orlando Sentinel/Tribune News Service/Getty Images

NASA and its space aviation partners are in the midst of a major problem. Their newest human-rated spacecraft, Boeing’s Starliner, is in the middle of a string of issues. The latest? A second helium leak. While it might seem easy to place full blame on Boeing, in reality, rocketry is, put simply, extremely difficult.

Boeing and SpaceX received contracts a decade ago to build out the space agency’s Commercial Crew Program. This would see astronauts launch into space from American soil for the first time since the Space Shuttle retired. In the interim, NASA paid Russia tens of millions of dollars to purchase individual seats on their Soyuz spacecraft. This mostly wrapped up when SpaceX’s Crew Dragon aced its summer 2020 astronaut debut flight.

Boeing’s Starliner is meant to join the Crew Dragon as a go-to transportation vehicle, but its been delayed longer than expected. Earlier this month, it was moments from flying Suni Williams and Butch Wilmore to the International Space Station. But two hours before the targeted launch window, officials from the company that supplied the rocket, United Launch Alliance, recommended standing down. The initial problem was a liquid oxygen valve. That was swiftly addressed. But as teams reviewed the crew capsule, they detected a helium leak. That, too, was quickly fixed. But a new, unrelated, helium leak has now emerged.

Helium is important because it allows the spacecraft thrusters to fire, and isn’t combustible or toxic, according to NASA.

NASA will conduct a flight readiness review probably next week, the space agency reported on Thursday. The new target launch date is June 1.

PUTTING THE DELAY INTO PERSPECTIVE

Delays stemming from mechanical issues are not uncommon.

Even tried and tested launch vehicles, like the SpaceX reusable Falcon fleet, have experienced ongoing issues like corrosion from salt water.

When the SpaceX Crew Dragon was at the same stage as the Boeing Starliner is now, with a successful uncrewed docking at the orbiting laboratory under its belt, and in the midst of preparations for sending its first astronauts into space, the Crew Dragon literally blew up.

As CBS News reported in 2019, teams were just about to fire up its “fault-tolerant propulsion” engines, which would bring the crew capsule away from the rocket in less than eight seconds in case of an emergency during liftoff. But just before beginning this test of its launch escape system, there was an anomaly. Beachgoers witnessed reddish-orange smoke rising after the incident. Crew Dragon didn’t fly its first astronauts, for the Demo-2 mission, until a year later.

Artemis I, NASA’s most-recent foray around the Moon with a human-rated spacecraft, is another example of this liminal space.

The premier mission of the Artemis program established that the Orion capsule could successfully swing out past the Moon, farther than any such spacecraft has flown before, and land back on Earth, coming in faster and hotter than Apollo astronauts ever did. But the first trip with astronauts, Artemis II, has been delayed by a year due to an issue with the heat shield. Charred material unexpectedly came off the capsule during descent, posing a potential risk to the integrity of the spacecraft if it happened to be entering a different orientation than its entry in late 2022.

In the grand scheme of spaceflight history, delays tend to fade from memory. What people remember is the awe of a successful trip, and the sad moments when they’ve failed. Space is undeniably hard.

{ https://www.inverse.com/ }

29-05-2024 om 00:37 geschreven door peter  

Cornell University

Someday, she hopes that the vials of well-tended microbes, tiny samples of hot lava, and thousands of lines of computer code in her labs will help astronomers recognize the chemical signs of life in the atmosphere of a distant planet.

In her recent book, Alien Earths: The New Science of Planet Hunting in the Cosmos, Kaltenegger describes the result as a “light fingerprint” for life (and one of its telltale features is a combination of oxygen and methane).

Inverse talked with Kaltenegger about exoplanets, aliens, and how science mixes caution with optimism.

Kaltenegger: I started thinking about how to do this in 1999 or 2000, and I really started modeling it around 2004. People were finding the first planets in the habitable zone, but it was with the wobble technique, so we didn't really know their mass; they could still be gas balls or rocks. It took about a decade until 2013, until we found the first Kepler planets in the habitable zone that were small enough to be rocky.

It was a long stretch where there were still some hints that those planets would exist, like from radial velocity measurements, but we just were unsure.

I think when we found that first exoplanet around another star, it was an educated guess that there should be other ones. But the one problem we had was the timeline; that the work would be needed at some point seemed like a logical conclusion, but the problem was, was it going to be within my lifetime? There were people telling me that this was way too far advanced, that this is something nobody would need in our lifetimes. And I usually fall back to this idea that I have on science, that you're basically putting these stepping stones into place. Even if it might not be you who actually can do the observations, the ideas that we put together can vibrate through time.

I usually fall back to this idea that I have on science, that you're basically putting these stepping stones into place. Even if it might not be you who actually can do the observations, the ideas that we put together can vibrate through time.

Your book describes one lab full of colorful microbe colonies in vials, and another where you actually make lava by melting powdered rock samples. That sounds like so much fun! What is your normal work day like?

I work a lot on my computer. What I do most of the time is actually putting these pieces together and putting it into this atmospheric model to figure out how these signs of life would appear to a telescope. I do get to go to the biology lab, to the Earth and atmospheric lab, and to the lava lab.

But I have people who actually have those as their specific things, because otherwise I could get going and forget to feed the bacteria. I could see myself forgetting something critical. In our team, we have a person who trained in microbiology who's growing most of these biota, so that's a big step forward from me killing half of the biota when I tried this. And then we have somebody else whose specific expertise is lava, that actually knows how to handle molten rock. I have to say in my head 'Don't touch it, it's molten rock.'

Your tone in the book is very hopeful. How optimistic are you that we’ll detect life on another planet during your career?

We have billions and billions of possibilities out there, so I think the numbers are forever in our favor. The question is how to spot it, and this is what we are learning.

It requires these databases of signatures, like biopigments, that you could see as mixtures of gases in an atmosphere. It requires you to understand your data well, and to understand the star well. Where we are right now is learning how to take the star's signal out to figure out what's going on with the small planets, and the TRAPPIST-1 system is the one that we've started with. It's really hard to do even with the biggest telescope we have.

We have billions and billions of possibilities out there, so I think the numbers are forever in our favor. The question is how to spot it, and this is what we are learning.

One of the first questions that I asked myself is if you looked at the Earth through time, how long could you have spotted life? Because that was a completely open question. Just in terms of how long Earth's atmosphere has had unique signatures of life, it's about half the planet's lifetime, so 2 billion years. If we assume that the evolution of a planet is the same everywhere, time-wise, then I think we have a great chance to find signs of life. If the evolution of life to do photosynthesis and produce oxygen is faster, then we have a higher chance. If it's slower, then it's going to become more tricky to identify it. But being that generation and the group of people who figure out what this probability is, is actually a fascinating journey.

So how optimistic am I? The bigger surprise to me would be if we find nothing. If life is everywhere it can be, and it developed to leave unique signs, then we have a shot with the JWST in the next 5 to 10 years.

Speaking of TRAPPIST-1, some of the first round of observations with JWST have been pretty discouraging; it looks like the innermost TRAPPIST-1 planets may not have much in the way of atmospheres. What does this mean for the odds of life on rocky worlds in the habitable zones of red dwarf stars?

The problem is that if you make a certain assumption for the model of the star, and you apply it to your data, you get a solution. Then you come to the second observation, and we figure out the star is actually completely different than we thought it was. The problem is that results in error bars that are very big, and those big error bars do not preclude us from saying either way if there's an atmosphere enough, so I'm not worried yet. Once we have beaten down the error bars from the star, if we still don't find anything, then it can exclude things like a Martian atmosphere. But we're not there yet.

Currently, what [the JWST data] means is that we can exclude a 'substantial atmosphere,' but the Earth doesn't have a 'substantial atmosphere.' We never expected the TRAPPIST systems to have 10 or 100 bars of hydrogen and CO2, because they're too small, so it's not really surprising, what we've found.

Let's assume that that we find there is no atmosphere on any of the TRAPPIST-1 planets. That actually doesn't mean that the next M star over will also have planets with no atmosphere. TRAPPIST-1 is of the smallest systems, extremely active, and very tightly packed. In science, we have to be very careful not to take one example and extrapolate it to everything else.

Once you find an exoplanet atmosphere with a mix of chemicals that looks like a fingerprint of life, how do you decide when to make the ‘we found aliens’ claim?

The scientific community generally agrees on something called three sigma detection. When you run the model, and it does machine learning and lots of super cool things to figure out what's in the atmosphere [of an exoplanet], if that signal doesn't hit the three times higher than the noise, a lot of times [those signals] are artifacts. And so we've already seen this when we have the first hints that there could be dimethyl sulfide [in a planet’s atmosphere] — that is like a 1.2 sigma, so not anywhere near this threshold yet.

And then I think what needs to happen is that the data needs to be scrutinized by way more than one team. Because you never know; there could be an error in your model, or there could be something you program differently that gives you better results than other teams.

If two independent teams find a confirmation, then the next step is you put all the criticism you can out there: What else could it be? Like exotic geophysics or photochemistry. That's what I do with the light fingerprints, to say [when a planet] might look like it has life, but it doesn't — under what circumstances do we have to be very careful? It's not to say that I'm not excited every time someboday says 'Oh, this could be life.' But it's like the methane on Mars; I wish for it to be life, but if I have 99 or 100 explanations that don't require life, then as a scientist, I do have to say, 'I wish it were life, but it seems like that it's not.'

The more the planet becomes not Earth-like, the more cautious we have to be with our interpretation of the results.

Your book describes a lot of really strange, interesting planets — some you’ve simulated in your lab, and some you’ve actually studied telescope data from. Of all of them, which do you think would make the most interesting science fiction story?

So, when we found Kepler 62 e and f, the two first Kepler words: Just the vision that this would be a water world, that when you dive in, there would be ice on the bottom of this ocean, which because of the pressure, would be warm ice. There would be waves that would never break.

The other one that I'd love to see a sci-fi novel about is that giant planet we found around the white dwarf. We can only wonder, when the star exploded, did they go underground and shelter through the explosion of the star? Did they have any idea if they could survive this? You know that the white dwarf, even over billions of years, would get colder, so they would actually have to do climate change – create as much CO2 as humanly possible. And so I think that would be a super cool sci-fi plot, where your planet or moon is a spaceship that goes to the exploded planet of a star, and that's where you have to survive.

{ https://www.inverse.com/ }

28-05-2024 om 21:31 geschreven door peter  

Venus is Currently Volcanically Active, New Study Confirms

Using radar data from NASA’s Magellan mission, planetary scientists have detected volcanic-related flow features in two different regions of Venus: on the western flank of Sif Mons and in western Niobe Planitia.

This image shows the Sif Mons area with the active volcanic region highlighted in red. Image credit: Davide Sulcanese, IRSPS – Università d’Annunzio.

Venus’ thick atmosphere has made it difficult to directly observe the surface of the planet.

However, global radar mapping performed in the 1990s by the Magellan spacecraft showed that Venus’ surface is covered with many volcanoes and has likely been shaped by widespread volcanic activity in its past — though the role of volcanism in the planet’s geologic present remained unclear.

However, evidence of more recent activity from one volcanic vent on the planet’s surface was identified in the Magellan data in 2023.

In the new study, d’Annunzio University researcher Davide Sulcanese and his colleagues analyzed two sets of Magellan radar data obtained in 1990 and 1992 to look for evidence of volcanic activity.

They found surface changes that could indicate volcanism in two areas where volcanic-related features are present, located on the western flank of Sif Mons and in western Niobe Planitia.

After analyzing the various possible sources, the authors suggest that these variations were likely caused by fresh lava flows.

They suggest that Venus is a geologically active planet in the present day, but also that present-day volcanism is rather widespread.

They also suggest that volcanic activity on Venus is comparable to that of Earth, indicating that Venus is more volcanically active than previously thought.

Artist’s impression of a volcano erupting on Venus. Image credit: ESA / AOES Medialab.

“Using these maps as a guide, our results show that Venus may be far more volcanically active than previously thought,” Dr. Sulcanese said.

“By analyzing the lava flows we observed in two locations on the planet, we have discovered that the volcanic activity on Venus could be comparable to that on Earth.”

“We interpret these signals as flows along slopes or volcanic plains that can deviate around obstacles such as shield volcanoes like a fluid,” added Dr. Marco Mastrogiuseppe, a researcher at Sapienza University of Rome.

“After ruling out other possibilities, we confirmed our best interpretation is that these are new lava flows.”

“These new discoveries of recent volcanic activity on Venus provide compelling evidence of the kinds of regions we should target with NASA’s upcoming VERITAS mission when it arrives at Venus,” said Dr. Suzanne Smrekar, a researcher at NASA’s Jet Propulsion Laboratory and principal investigator for VERITAS.

“Our spacecraft will have a suite of approaches for identifying surface changes that are far more comprehensive and higher resolution than Magellan images.”

“Evidence for activity, even in the lower-resolution Magellan data, supercharges the potential to revolutionize our understanding of this enigmatic world.”

• The results were published this week in the journal Nature Astronomy.
• D. Sulcanese et al. Evidence of ongoing volcanic activity on Venus revealed by Magellan radar. Nat Astron, published online May 27, 2024; doi: 10.1038/s41550-024-02272-1

{ https://www.sci.news/ }

28-05-2024 om 19:58 geschreven door peter  

28-05-2024 om 18:29 geschreven door peter  

NASA-foto's tonen het ruimtepak zoals het nog nooit eerder is gezien: zonder armen en vizieren

 Door Janine

Dat NASA van plan is terug te keren naar de maan met een menselijke bemanning is geen mysterie. Ter voorbereiding op de Artemis III-missie testte de Amerikaanse ruimtevaartorganisatie enkele nieuwe technologieën voor toekomstige maanwandelingen. Daarvoor stuurde het enkele astronauten naar een vulkanisch veld in de staat Arizona, maar met een heel speciale uitrusting. Laten we eens kijken waar het om gaat!

De reden voor de NASA-tests in Arizona

NASA/Josh Valcarcel

We bevinden ons in Arizona, in de Verenigde Staten, en meer precies in het vulkanische veld San Francisco, dat bestaat uit meer dan 500 vulkanische kloven. Dit is een ideale omgeving, onder de omstandigheden die hier op aarde beschikbaar zijn, om de apparatuur te testen waarmee het mogelijk zal zijn om met de Artemis III-missie naar de maan te gaan. Nadat ze speciale ruimtepakken hadden aangetrokken, simuleerden de astronauten enkele maanwandelingen, om op alle eventualiteiten voorbereid te zijn.

Twee verschillende NASA-teams voerden de tests uit. Het eerste team bestaat uit vluchtleiders en wetenschappers van het Johnson Space Center en houdt op afstand toezicht op de activiteiten van de astronauten. Het tweede team bestaat uit ingenieurs en werkt in het veld en voert “maanwandelingen” uit in de woestijn van Arizona.

Is alles klaar voor de Artemis III-missie?

NASA/Josh Valcarcel / NASA

Bij de vier door NASA gesimuleerde maanwandelingen maakten de teams gebruik van augmented reality-displays en navigatie met heldere lichten. Maar als je naar de gedeelde foto’s kijkt, is het bijzondere ontwerp van de ruimtepakken die de astronauten gebruikten duidelijk. Kort gezegd: ze zien er beslist incompleet uit.

De waarheid is dat het testen op Artemis III op verschillende locaties plaatsvindt en verschillende doeleinden heeft. In Arizona is het niet nodig om de hele opstelling van het ruimtepak uit te proberen, maar eerder om de werking van enkele componenten te evalueren tijdens een wandeling over het oppervlak van onze satelliet. Dit zijn simulaties waarvan het belang voor het succes van missies te vaak wordt gebagatelliseerd. In werkelijkheid maken tests zoals die in Arizona het mogelijk om te oefenen in geologische omstandigheden die vergelijkbaar zijn met die op de maan: eenmaal daar zul je immers niet gemakkelijk naar huis kunnen terugkeren.

Van Arizona tot de zuidpool van de maan

NASA/Josh Valcarcel

De gesimuleerde maanwandelingen met de vreemde ruimtepakken zijn momenteel de meest getrouwe simulatie van de Artemis III-missie die tot nu toe is uitgevoerd. De omstandigheden in de woestijn van Arizona lijken immers erg op die van de maangrond waarop de astronauten zich voorbereiden om te betreden.

Het doel van de veldtesten is immers om de uitdagingen die de Artemis III-missie op de zuidpool van de maan zal tegenkomen beter in te schatten. Deze omvatten het verzamelen van gegevens en communicatie met het team dat de vlucht bestuurt en het wetenschapsteam in Houston. Kortom: het duurt niet lang meer voordat een bemanning astronauten terugkeert naar de maan, en het is beter dat alles tot in de puntjes geregeld is. Misschien zullen er nog steeds onvoorziene gebeurtenissen plaatsvinden, maar dat betekent niet dat je niet voorbereid kunt zijn door in vreemde ruimtepakken rond te lopen in de woestijn van Arizona.

{ https://www.curioctopus.nl/ }

27-05-2024 om 20:58 geschreven door peter  

Japan ontwerpt de eerste ruimtelift: hij zal klaar zijn in 2050

 Door Janine

Tot voor kort betekende praten over een ruimtelift dat je je op sciencefictionterrein begaf. In staat zijn om naar een ruimtestation in een baan om de aarde te gaan zonder gebruik te maken van een ruimteschip lijkt iets onrealistisch, maar toch is het een steeds reëler wordende mogelijkheid. Het nieuwste bedrijf dat aan dit ambitieuze project is begonnen, is de Japanse Obayashi Corporation. Maar is het echt mogelijk om een ruimtelift te bouwen? En wanneer zal hij klaar zijn? Laten we daar samen achter komen!

Wat is een ruimtelift?

Liftport/Wikimedia Commons - CC BY-SA 3.0 DEED

Een ruimtelift is een hypothetische constructie die het aardoppervlak moet verbinden met een geostationaire baan, zo'n 36.000 kilometer boven de aarde. Dit speciale transportmiddel zou werken als een klassieke lift, met cabines die langs een lange, sterke kabel omhoog en omlaag gaan. Kortom, een ruimtelift zou mensen en goederen in de ruimte kunnen vervoeren zonder dat daar raketten en ruimtevaartuigen voor nodig zijn.

Hoewel het idee op zich niet nieuw is - een eerste vermelding dateert al uit 1895 - lijkt de aanpak van de Obayashi Corporation een concrete interesse in de realisatie van de eerste ruimtelift op aarde te bevestigen. Aan de andere kant zou zo'n constructie enorme voordelen bieden bij het transport van en naar de ruimte, maar tegelijkertijd ook aanzienlijke uitdagingen met zich meebrengen.

Het idee van Obayashi Corporation

大林組広報部/Youtube

De realisatie van een ruimtelift zou mogelijk worden gemaakt door de vooruitgang in het onderzoek naar koolstofnanobuizen, dat de kern van het project vormt. Volgens de Obayashi Corporation zou deze ruimtelift zich over ongeveer 96.000 kilometer van de aarde naar de ruimte kunnen uitstrekken en resistente kabels gebruiken om mensen en goederen naar een ruimtestation in een geostationaire baan te brengen. Op deze manier zou de omwentelingsperiode van het station gelijk zijn aan de rotatieperiode van de aarde.

Voor de bouw van de lift zijn echter verschillende stappen nodig. Eerst zouden materialen door raketten naar een lage baan om de aarde worden gestuurd, waar ze zouden worden gebruikt om een ruimtestation in elkaar te zetten dat wordt aangedreven door elektromotoren. Eenmaal klaar zou dit ruimteschip een geostationaire baan moeten bereiken om vervolgens de kabel naar de aarde te verlengen. Eenvoudig, toch?

Is een ruimtelift echt haalbaar?

大林組広報部/Youtube

Volgens Obayashi Corporation zeker wel. Het bedrijf wil zo snel mogelijk beginnen met de bouw en de ruimtelift operationeel hebben voor 2050, met alle positieve gevolgen voor de kosten van ruimtevaart, koolstofuitstoot en het transport van mensen en goederen.

Kortom, vandaag de dag wil het idee van een ruimtelift meer dan ooit breken met science fiction en onze dagelijkse realiteit binnendringen. In theorie is dit een haalbaar project, maar het vergt een gecoördineerde internationale inspanning. Velen zien het project wellicht als slechts een poging van de mens om het bereik van zijn doelstellingen uit te breiden naar de ruimte, duizenden kilometers voorbij het Internationale Ruimtestation. En dit behoort zeker ook tot de doelstellingen van de Obayashi Corporation, maar dat niet alleen. Het is ook een poging om iets werkelijkheid te laten worden wat tot voor kort alleen een verbeelding was. Een toekomstige realiteit, zeker, maar een concrete en tastbare realiteit.

Source:

• https://www.obayashi.co.jp/en/news/detail/the_space_elevator_construction_concept.html

{ https://www.curioctopus.nl/ }

26-05-2024 om 23:51 geschreven door peter  

Een oude Maya-techniek zou de groei van planten op Mars kunnen bevorderen, zo beweert een onderzoek

 Door Janine

Vroeg of laat zullen mensen naar Mars gaan. Misschien zal de missie niet in de nabije toekomst plaatsvinden, maar het staat vast dat het koloniseren van de rode planeet een van de doelstellingen van ruimtevaartorganisaties is. De vraag is: wat zullen toekomstige kolonisten eten? Leveringen vanaf de aarde zijn allesbehalve duurzaam, en dus blijft er maar één optie over: voedsel direct op Mars verbouwen, met enige hulp van oude Maya-praktijken.

De Maya's en de landbouw op Mars

PLOS ONE/Gonçalves et al./2024

De voedselvoorziening en de landbouw op Mars zijn verre van een ondergeschikt probleem, maar uiterst belangrijke kwesties. Met name een onderzoek van Wageningen University & Research in Nederland heeft mogelijk de eerste stappen gezet om het probleem op te lossen. De onderzoekers hebben in feite een moderne versie van een oude Maya-techniek overgenomen, genaamd intercropping of tussenteelt, en zijn begonnen met het telen van tomaten, erwten en wortels in dezelfde potten.

De resultaten, gepubliceerd in PLOS ONE, waren verrassend. Tomaten geteeld door middel van tussenteelt verdubbelden hun productie vergeleken met individueel geteelde tomaten, met grotere vruchten en in minder tijd. Hetzelfde gebeurde niet met erwten, die een onveranderde opbrengst behielden, en wortelen, die daarentegen een lagere opbrengst vertoonden. Terwijl aan de ene kant intercropping veelbelovende resultaten oplevert, is het aan de andere kant essentieel om zorgvuldig gewassen, grond en additieven te kiezen.

Verbouwen op Marsgrond: is dat mogelijk?

PLOS ONE/Gonçalves et al./2024

Bij het experiment van de onderzoekers van de Nederlandse universiteit waren in deze eerste fase drie soorten gewassen betrokken. Zoals we al zeiden, zijn de grondsoort en eventuele toevoegingen even belangrijk. Om de bodem van Mars te simuleren, ontwikkelden wetenschappers een bodem die bestaat uit regoliet, zonder organisch materiaal, waaraan ze vervolgens bacteriën en voedingsstoffen toevoegden. Een proces dat sterk lijkt op het proces dat toekomstige kolonisten zouden kunnen gebruiken om gewassen op Mars te verbouwen.

Als aanvoer vanaf de aarde moet worden uitgesloten vanwege de kosten en tijd die daarvoor nodig is, lijkt teelt op de rode planeet de enige optie. En intercropping, oftewel het gebruik van planten met complementaire eigenschappen, zou echt een levensvatbare toekomst kunnen vertegenwoordigen. Evenals een manier om het gebruik van water en voedingsstoffen te optimaliseren.

De nieuwe landbouw op Mars en de kunst van het kiezen van de juiste planten

PLOSE ONE/Gonçalves et al./2024 / 中国新闻网/Wikimedia Commons - CC BY 3.0 DEED

Uit de resultaten van hun experiment ontdekten de onderzoekers dat de tomatenplanten een concreet voordeel haalden uit de nabijheid van erwten. Deze laatste kunnen namelijk zeer efficiënt stikstof uit de lucht opnemen en omzetten in voedingsstoffen. Tegelijkertijd profiteerden de wortels niet alleen niet van de nabijheid van de erwten, maar werden ze er ook door geschaad, waarschijnlijk als gevolg van de concurrentie om licht. En we weten dat zonlicht op Mars niet in grote hoeveelheden beschikbaar is: ook in dit geval zal het nodig zijn om na te denken over duurzame alternatieven voor een menselijke kolonie.

Het succes van toekomstige missies naar de rode planeet hangt inderdaad ook af van het vermogen van de kolonisten om zelfvoorzienend te zijn. En deze capaciteit hangt op zijn beurt af van duurzame landbouw op Marsgrond, dat wil zeggen van de tussenteelt van de oude Maya’s. Naast het kiezen van de juiste gewassen om het project te starten, rest er vandaag nog maar één twijfel: niemand heeft de tomaten, erwten en wortelen geproefd. Wie weet hoe ze zullen smaken.

{ https://www.curioctopus.nl/ }

25-05-2024 om 17:19 geschreven door peter  

{ https://www.universetoday.com/ }

25-05-2024 om 17:06 geschreven door peter