Scientists find signs of earliest life on Earth after 3.5 billion-year-old discovery

Researchers have discovered biological material some 3.5 billion years-old hidden in remote, crystal-clear lagoons.

Located more than 12,000 feet above sea level on Argentina’s Atacama Plateau near the Chile-Bolivia border are shallow lakes that are home to stromatolites – rocky masses of calcareous material and sediment formed by the prolific growth of photosynthesising microbes called cyanobacteria.

Stromatolites (Greek for "layered rock") are living fossils found only in a few salty lagoons or bays on Earth. Their unique ecosystem provides a glimpse into what Earth was like billions of years ago, when primitive organisms first appeared on the planet.

Geologist Brian Hynek said: "They could be one of the best modern examples of the earliest signs of life on Earth. It’s unlike anything I’ve ever seen or, really like anything any scientist has ever seen. It’s just amazing that you can still find undocumented things like that on our planet."

Hynek first noticed the network of lagoons last April, when he was looking through satellite images of the Atacama Plateau. He and microbiologist Maria Farias proceeded to drive as far as they could towards the formations and hike several miles in the sun.

"In some places, we were sinking up to our knees in salt slush," Hynek recalled. Some of the stromatolites they found were about 15 feet across and several feet high, resembling giant green mounds.

He believes the unforgiving environment of the Atacama Plateau – a cold, desolate zone where rainfall is rare and sun exposure is nearly constant – is similar to the harsh conditions of ancient Earth, when oxygen was almost nonexistent in the atmosphere. And he hopes the discovery may aid the search for life on Mars.

"If life ever evolved on Mars to the level of fossils, it would have been like this. Understanding these modern communities on Earth could inform us about what we should look for as we search for similar features in the Martian rocks," Hynek explained.

Hynek and co-researcher microbiologist Maria Far plan to carry out further experiments but an international company has already earmarked the area for lithium mining, so time is running out.

"This entire, unique ecosystem could be gone in a matter of years," Hynek said. "We’re hoping that we can protect some of these sites, or at least detail what’s there before it’s gone or disturbed forever."

Modern stromatolites can be found elsewhere on Earth today, such as off the coast of the Bahamas and in parts of Australia, but they tend to be small. In contrast, their ancient predecessors could stretch to 20 feet tall and grew by sucking in calcium and carbon dioxide from the surrounding water.

Source: https://www.msn.com/en-za/news/world/scientists-find-signs-of-earliest-life-on-earth-after-3-5-billion-year-old-discovery/ar-AA1lCAj4?ocid=msedgdhp&pc=U531&cvid=0a3c662f54b541cca2956689a1ddc274&ei=69

Astronomy: What happened when the moon turned itself inside out billions of years ago?

Over 4.2 billion years ago, the moon turned itself inside out to create the lunar surface that has become familiar to humanity.

Most scientists would agree the moon was created around 4.5 billion years ago, when another massive body in the solar system smashed into Earth, flinging molten material into space that coalesced as our natural satellite.

How the birth of the moon proceeded after this violent start, however, has been described as "more of a choose-your-own-adventure novel" by a team of scientists from the University of Arizona’s Lunar and Planetary Laboratory (LPL).

They say there are many possible paths Earth’s natural satellite could have taken to form in full, ultimately leading to the moon-Earth system we see today. The team of course has its own ideas about the major incidences that might have formed the moon. The researchers say rock samples collected during the Apollo mission, for instance, may indicate there was a time when the moon "flipped inside out."

This result, if true, might also solve a lingering mystery about the moon’s composition.

"Our moon literally turned itself inside out," research co-author and LPL associate professor Jeff Andrews-Hanna said in a statement. "But there has been little physical evidence to shed light on the exact sequence of events during this critical phase of lunar history, and there is a lot of disagreement in the details of what went down — literally."

Titanium on the near side of the moon?

Basaltic lava rocks brought back from the moon have shown surprisingly high concentrations of titanium. In addition to this, satellite observations have revealed that titanium-rich volcanic rocks are primarily located at the lunar nearside. This left scientists scratching their heads about how these particular rocks got there and aren’t more widely dispersed.

The University of Arizona team suggests the moon formed rapidly, leaving it entirely covered with a hot magma ocean at first. As this ocean cooled and hardened, it would have formed the outer layers of the moon, including its mantle and crust. Yet, at lower layers, the infant moon would have still been in turmoil.

Models of moon formation suggest the last remains of this giant lunar ocean crystallized into dense materials including ilmenite, a mineral rich in iron and titanium.

"Because these heavy minerals are denser than the mantle underneath, they create a gravitational instability, and you would expect this layer to sink deeper into the moon’s interior," said research leader and former LPL doctoral candidate Weigang Liang, said.

Three diagrams of the moon, slightly overlain.

Questions remain: Would this material sink all at once as a single "blob" after the moon solidified, or a little at a time as smaller blobs? And, if it sank within the interior of the moon on a global scale, how did some of it rise to carry titanium to the moon’s nearside?

"Without evidence, you can pick your favorite model," researcher co-lead author and German Aerospace Center scientist Adrien Broquet said in the statement. "Each model holds profound implications for the geologic evolution of our moon."

Co-author and Peking University scientist Nan Zhang previously developed models that suggested a giant impact on the moon could have caused a dense layer of titanium-rich material beneath the crust to shift to its nearside. Once there, this material would have sunk, formed sheet-like slabs and cascaded to the interior of the moon, leaving a remnant beneath the crust in the form of intersecting bodies of dense titanium-rich deposits.

"When we saw those model predictions, it was like a lightbulb went on," Andrews-Hanna said. "We see the exact same pattern when we look at subtle variations in the moon’s gravity field, revealing a network of dense material lurking below the crust."

The GRAIL of moon formation models
To solidify its molten theories of titanium-rich ilmenite material and observations of the moon, the team turned to data surrounding lunar gravity anomalies detected by NASA’s Gravity Recovery and Interior Laboratory (GRAIL) dual-spacecraft mission.

"Analyzing these variations in the moon’s gravity field allowed us to peek under the moon’s surface and see what lies beneath," Broque said.

This confirmed that GRAIL data conforms with ilmenite layer simulations.

Such confirmation also showed that gravity-field observations could be used to trace the distribution of ilmenite remnants left behind after a majority of the dense layer had sunk to the deep interior of the moon.

"Our analyses show that the models and data tell one remarkably consistent story," Liang said. "Ilmenite materials migrated to the nearside and sunk into the interior in sheet-like cascades, leaving behind a vestige that causes anomalies in the moon’s gravity field, as seen by GRAIL."

An artist’s illustration shows two solar-winged spacecraft connected by wiggly lines representing communication. The lines extend to Earth; the spacecraft float above the moon.

The team was also able to determine when the moon flipped inside out. They say the interruption of gravity anomalies by large and ancient lunar impact basins indicates the ilmenite-rich layer sank prior to these impacts. This "cross-cutting" means the sinking event would have happened earlier than 4.22 billion years ago, indicating that the sinking could have triggered volcanism, which was seen at later times across the lunar surface.

This research also adds nuance to an interesting picture of the moon we see today. The overturn of the lunar mantle billions of years ago would have led to the creation of a dark region known as the Oceanus Procellarum region, as well as on the side of the moon close to Earth.

This area of the moon is lower in elevation and has a thinner crust that’s mostly blanketed by lava flows unlike the thicker crust of far side regions of the moon. It also has a higher concentration of rare elements like titanium and thorium. "The moon is fundamentally lopsided in every respect," Andrews-Hanna said. "For the first time, we have physical evidence showing us what was happening in the moon’s interior during this critical stage of its evolution, and that’s really exciting.

"It turns out that the moon’s earliest history is written below the surface, and it just took the right combination of models and data to unveil that story."

Broquet added: "The vestiges of early lunar evolution are present below the crust today, which is mesmerizing.

"Future missions, such as with a seismic network, would allow a better investigation of the geometry of these structures."

The findings could also help inform future investigations of our loyal lunar companions if and when, in 2025, NASA’s Artemis III mission returns humanity to the moon for the first time since the Apollo missions drew to an end 50 years ago.

"When the Artemis astronauts eventually land on the moon to begin a new era of human exploration," Liang concluded. "We will have a very different understanding of our neighbor than we did when the Apollo astronauts first set foot on it."

The team’s research is published in the journal Nature Geoscience.

Source: https://www.space.com/moon-inside-out-billions-years-ago

Astronomy: The only Oceans ever discovered on another world: Titan’s weird oceans

[Remember Titan is insanely cold, so these are not even oceans composed of water. These are liquid hydrocarbon lakes, seas and rivers. Sadly this is a paid article and this is all I can show you now. I'll try to find other info on this. This is really fascinating. Jan]

Our most detailed look yet at the strange lakes of Saturn’s moon Titan has revealed a diverse seascape, similar to Earth’s combination of freshwater rivers and salty oceans.

Source: https://www.newscientist.com/article/2439695-moon-of-saturn-has-an-equivalent-of-freshwater-rivers-and-salty-oceans/?utm_source=nsday&utm_medium=email&utm_campaign=nsday_170724&utm_term=Newsletter%20NSDAY_Daily

Astronomy: Alien weather report: James Webb Space Telescope detects hot, sandy wind on 2 brown dwarfs

[I find the science relating to distant stars and planets fascinating. It is amazing the kinds of things they can deduce. The heroes you never hear about are the people who built the amazing equipment like the telescopes. Jan]

Coarse clouds of hot sand blow in the powerful winds of these two failed stars.

An illustration of the powerful storms and clouds of silicate found in the atmosphere of the brown dwarfs. (Image credit: NASA/JPL–Caltech/University of Western Ontario/Stony Brook University/Tim Pyle)
The James Webb Space Telescope (JWST) has discovered stormy weather in the sky of two brown dwarfs in the most detailed weather report yet from such "failed stars."

The two brown dwarfs form a binary pair called WISE 1049AB that was discovered by NASA’s Wide-field Infrared Survey Explorer (WISE) in 2013; the duo sits just 6.5 light-years away from us. They are the closest brown dwarfs to our sun, and thus make an excellent target for the James Webb Space Telescope’s powerful infrared instruments.

A brown dwarf is an object that isn’t quite massive enough to ignite the nuclear fusion of hydrogen to helium in its core and become a fully fledged star — yet is also considered too massive to be a planet and thought to form like stars do (via the gravitational collapse of a cloud of molecular gas). As such, brown dwarfs are thought of as a missing link between gas giant planets like Jupiter, and the lowest mass stars, M-dwarfs.

Previous observations have probed the atmosphere of various brown dwarfs, but they have always been limited to time-averaged snapshots, meaning we could not see things in the brown-dwarf atmosphere changing with time. However, brown dwarfs are fast rotators — WISE 1049A spins on its axis once every 7 hours, and B once every 5 hours — and the conditions in their atmospheres can alter over time, meaning that previous observations that didn’t factor in the objects’ evolutions could have missed lots of variability.

The JWST, however, does have the ability to detect these changes over time. A team led by Beth Biller of the University of Edinburgh observed WISE 1049AB for 8 hours with the JWST’s Mid-Infrared Instrument (MIRI), and then immediately afterward for another 7 hours with its Near-Infrared Spectrometer (NIRSpec).

The researchers found that both brown dwarfs are covered in tumultuous clouds, probably composed of silicate grains, sweltering in temperatures between 875 degrees Celsius (1,610 degrees F) and 1,026 degrees Celsius (1880 degrees F). In other words, hot sand is being blown in the winds of the brown dwarfs. The absorption signatures of carbon monoxide, methane and water vapor were also identified.

Intriguingly, the light curve for each brown dwarf (a graph of each brown dwarf’s brightness over time) displays considerable variability. This has been interpreted as stormy conditions blowing clouds at various altitudes, and gaps appearing between those clouds that allows for views into deeper layers of the atmosphere. The light curves also show peaks at specific wavelengths — carbon monoxide at 2.3 microns and 4.2 microns (millionths of a meter), methane at 3.3 microns, and silicate grains tentatively at 8.3 microns to 8.5 microns.

A large orange sphere in space. A smaller glowing object is in the background toward the left.

Biller’s team interpret the peaks at these wavelengths as indicating three different layers where there is a significant change in atmospheric pressure on each brown dwarf. There’s a deep layer producing signals greater than 2.3 microns but less than 8.5 microns, an intermediate altitude layer absorbing light at between 2.3 and 4.2 microns, and a high altitude layer with exhibiting signals between 4.2 and 8.5 microns.

The findings indicate the power of the JWST to be able to probe, for the first time, the vertical profile (i.e. the conditions at different depths) of the atmosphere of a brown dwarf, and, in fact, there’s no reason the JWST has to stop there. As the research paper describing the findings concludes: "This is the first such study, but will not be the last — in the next few observing cycles, JWST will transform our understanding of both brown dwarf and young, giant exoplanet atmospheres."

"Our findings show that we are on the cusp of transforming our understanding of worlds far beyond our own," said Biller in a statement. "Insights such as these can help us understand the conditions not just on celestial objects like brown dwarfs, but also on giant exoplanets beyond our solar system. Eventually, the techniques we are refining here may enable the first detections of weather on habitable planets like our own, which orbit other stars."

The findings were published on July 15 in the Monthly Notices of the Royal Astronomical Society.

Source: https://www.space.com/brown-dwarf-alien-weather-report-jwst?utm_term=AF536F6D-055D-443A-91F7-FD448D0CCA73&lrh=4cd1bd23c622eeb1274411ac3b55b43215b8c098a20f14a3285c9e8ae13a98ca&utm_campaign=58E4DE65-C57F-4CD3-9A5A-609994E2C5A9&utm_medium=email&utm_content=68A6599E-B1E6-4C4A-8A32-089A418403E1&utm_source=SmartBrief

Astronomy: Jupiter’s raging gas cyclones may actually mirror Earth’s oceans. Here’s how

Jupiter is essentially an "ocean of gas."

How different are Jupiter’s gaseous layers and Earth’s oceans? Perhaps not as much as you expect.

Lia Siegelman, a physical oceanographer at the University of California, San Diego’s Scripps Institution of Oceanography, has been studying Jupiter through the lens of Earth’s oceans to determine what powers the gas giant’s raging cyclones. "Jupiter is basically an ocean of gas," she said in a statement.

Siegelman’s original research, published in 2022, demonstrated that Jovian cyclones are powered by convection much in the same way Earth’s storms are. Following up on that study, she and her team are now analyzing filaments, or "wispy tendrils" found between the Jupiter’s vortices, seen in satellite imagery of the gas giant taken by NASA’s Juno spacecraft.

Calculating the horizontal wind speed of the world’s clouds and filaments through an analysis of infrared images, Siegelman noticed that the filaments appeared to behave similarly to fronts in Earth’s ocean and atmosphere, like cold fronts or storm fronts. These fronts represent a boundary between masses with different densities (on Earth, that’s usually dependent on temperature of the atmosphere and salinity of the ocean). Fronts are typically associated with strong winds or currents along their edges, which could help power Jupiter’s cyclones.

The team then used methods from oceanography and atmospheric science to calculate the vertical wind speeds of the filaments, which confirmed the similarity in behavior between Earth-based fronts and Jovian ones. Through this process, the team determined that the filaments help transport heat energy from Jupiter’s interior to its upper atmosphere, thus contributing to approximately "a quarter of the total kinetic energy powering Jupiter’s cyclones and forty percent of the vertical heat transport," per the statement.

"It’s fascinating that fronts and convection are present and influential on Earth and Jupiter — it suggests that these processes may also be present on other turbulent fluid bodies in the universe,” said Siegelman. "There is some cosmic beauty in finding out that these physical mechanisms on Earth exist on other faraway planets."

Source: https://www.space.com/jupiter-gas-cyclones-earth-oceans