Personally, I don't think there's intelligent life on other planets. Why should other planets be any different from this one?

— Bob Monkhouse

Astronomy

Should we be worried about a bird flu pandemic in the US?

New Scientist Space - Space Headlines - Thu, 04/04/2024 - 1:27pm
One person in the US has contracted bird flu after being exposed to dairy cows that have the virus, but experts say there is no immediate threat of a wider outbreak in people
Categories: Astronomy

Perseverance Finds its Dream Rock

Universe Today - Thu, 04/04/2024 - 1:02pm

If there’s a Holy Grail on Mars, it’s probably a specific type of rock: A rock so important that it holds convincing clues to Mars’ ancient habitability.

Perseverance might have just found it.

If scientists could design the perfect rock for Perseverance to find, it would be one that displayed evidence of ancient water and was the type that preserves ancient organic material. The rover may have found it as it explores the Margin Unit, a geologic region on the inner edge of Jezero Crater’s rim. The Margin Unit was one of the reasons Jezero Crater was selected for Perseverance’s mission.

“To put it simply, this is the kind of rock we had hoped to find when we decided to investigate Jezero Crater.”

Ken Farley, Perseverance project scientist, Caltech.

The Margin Unit is in a narrow band along the crater’s western rim. Orbital observations showed that it’s one of the most carbonate-rich regions on the planet. “Its presence, along with the adjacent fluvial delta, made Jezero crater the most compelling landing site for the Mars 2020 <Perseverance> mission,” presenters at the 2024 Lunar and Planetary Science Conference wrote.

The Margin Unit lies near the western rim of Jezero Crater. White dots show Perseverance’s stopping points, and the blue line shows the rover’s future route. Image Credit: R.C. Wiens et al. 2024

The decision to send Perseverance to the Jezero Crater and the Margin Unit seems to be paying off. Bunsen Peak caught scientists’ attention because it stands tall compared to its surroundings. One of the rock’s faces also has an interesting texture. Scientists thought the rock would allow for nice cross-sections, and since it stood vertically, there’d be less dust when working on it. Surface dust is a problem for Perseverance because it can obscure the rock’s chemistry.

The Perseverance team decided to sample it and cache the sample along with the rest of its cores for eventual return to Earth. But first, they scanned the rock’s surface with SuperCam and PIXL, the rover’s spectrometers. Then, they abraded the rock’s surface and scanned it again. The results show that Bunsen Peak is 75% carbonate grains cemented together by nearly pure silica.

This image mosaic shows the Bunsen Peak rock that has ignited scientists’ excitement. The rover abraded a circular patch to test its composition and extracted a core sample for return to Earth. The lighter surfaces are dust-covered, so Perseverance avoided those areas as the dust can obscure the rock’s chemistry from the rover’s instruments. Image Credit: NASA/JPL-Caltech/ASU/MSSS

“To put it simply, this is the kind of rock we had hoped to find when we decided to investigate Jezero Crater,” said Ken Farley, project scientist for Perseverance at Caltech in Pasadena, California. “Nearly all the minerals in the rock we just sampled were made in water; on Earth, water-deposited minerals are often good at trapping and preserving ancient organic material and biosignatures. The rock can even tell us about Mars’s climate conditions that were present when it was formed.”

This image shows the bottom of the Bunsen Peak sample core. The sample contains about 75% carbonate minerals cemented by almost pure silica. Image Credit: NASA/JPL-Caltech

Here on our planet, carbonate minerals can form directly around microbe cells. Once encapsulated, the cells can quickly become fossils, and are preserved for a long time. This is what happened to stromatolites here on Earth, and they now constitute some of the earliest evidence of life on our planet.

These minerals are a high priority for return to Earth. This sample is number 24, named Comet Geyser, because everything gets a name when you intend to transport it to Earth from another planet.

There’s something specific that makes this sample even more intriguing. They’re microcrystalline rocks, meaning they’re made of crystals so small that only microscopes can see them. On Earth, microcrystalline rocks like Precambrian chert hold fossilized cyanobacteria. Could the same be true of Bunsen Peak?

“The silica and parts of the carbonate appear microcrystalline, which makes them extremely good at trapping and preserving signs of microbial life that might have once lived in this environment,” said Sandra Siljeström, a Perseverance scientist from the Research Institutes of Sweden (RISE) in Stockholm. “That makes this sample great for biosignature studies if returned to Earth. Additionally, the sample might be one of the older cores collected so far by Perseverance, and that is important because Mars was at its most habitable early in its history.”

via GIPHY

Comet Geyser is Perseverance’s third sample from the Margin Unit. There’s still more work to do, but the samples support what scientists thought about Jezero Crater before Perseverance landed there: it was once a paleolake.

“We’re still exploring the margin and gathering data, but results so far may support our hypothesis that the rocks here formed along the shores of an ancient lake,” said Briony Horgan, a Perseverance scientist from Purdue University. “The science team is also considering other ideas for the origin of the Margin Unit, as there are other ways to form carbonate and silica. But no matter how this rock formed, it is really exciting to get a sample.”

It wasn’t that long ago that we knew very little about Mars. In the absence of knowledge, imagination took over. American astronomer Percival Lowell wrote three books about canals on Mars, popularizing the idea that intelligent life was extant on Mars and engineering the planet’s surface.

Astronomers didn’t buy the idea, which turned out to be untrue. But now we know that Lowell was at least partially, though inadvertently, correct. There are no canals, but there may have been lakes.

There was no intelligent life, but there may have been simple life in those lakes. Once we get Comet Geyser and the other samples back to Earth, we may find out for sure.

The post Perseverance Finds its Dream Rock appeared first on Universe Today.

Categories: Astronomy

There are hints that dark energy may be getting weaker

New Scientist Space - Cosmology - Thu, 04/04/2024 - 1:00pm
The standard model of cosmology says that the strength of dark energy should be constant, but tentative hints are emerging that it may have weakened recently
Categories: Astronomy

There are hints that dark energy may be getting weaker

New Scientist Space - Space Headlines - Thu, 04/04/2024 - 1:00pm
The standard model of cosmology says that the strength of dark energy should be constant, but tentative hints are emerging that it may have weakened recently
Categories: Astronomy

I screwed up and missed the solar eclipse in 2017. I won't make that same mistake on April 8.

Space.com - Thu, 04/04/2024 - 1:00pm
I didn't get to experience totality during 2017's solar eclipse, despite being just a few hours' drive away. I'm flying to Dallas so I don't make that mistake for the April 8 event.
Categories: Astronomy

To Ancient Maya, Solar Eclipses Signified Clashing Gods

Scientific American.com - Thu, 04/04/2024 - 1:00pm

Ancient Maya saw solar eclipses as a “broken sun” that was a sign of possible destruction

Categories: Astronomy

Decades-old Cans of Salmon Reveal Changes in Ocean Health

Scientific American.com - Thu, 04/04/2024 - 12:15pm

Researchers used tinned fish to reconstruct parasitic population change, giving new meaning to the phrase “opening a can of worms”

Categories: Astronomy

Exobiology Deputy Branch Chief Melissa Kirven-Brooks

NASA Image of the Day - Thu, 04/04/2024 - 12:09pm
“… I've just seen such tremendous things happen since I've been part of the Astrobiology Program, and that's why I'm pretty confident we're going to find life elsewhere, because there are just so many brilliant people working on this.” — Melissa Kirven-Brooks, Exobiology Deputy Branch Chief and Future Workforce Lead of the NASA Astrobiology Program, NASA’s Ames Research Center
Categories: Astronomy, NASA

Why some songs make our heart swell and others give us butterflies

New Scientist Space - Cosmology - Thu, 04/04/2024 - 12:00pm
Where in our body we feel the physical sensation of hearing music seems to depend on how surprising the piece's chords are
Categories: Astronomy

Why some songs make our heart swell and others give us butterflies

New Scientist Space - Space Headlines - Thu, 04/04/2024 - 12:00pm
Where in our body we feel the physical sensation of hearing music seems to depend on how surprising the piece's chords are
Categories: Astronomy

Colors will look different during the April 8 solar eclipse. Here's why

Space.com - Thu, 04/04/2024 - 12:00pm
When the moon fully eclipses the sun, it's not just the sky that changes. Your eyes do, too.
Categories: Astronomy

The Victorian Woman Who Chased Eclipses

Scientific American.com - Thu, 04/04/2024 - 12:00pm

Annie Maunder was an astronomer who expanded our understanding of the sun at the turn of the 20th century. Her passion was photographing eclipses.

Categories: Astronomy

'Star Trek: Discovery' season 5 episode 2 sows the seeds of seasonal plot threads (Under the Twin Moons recap)

Space.com - Thu, 04/04/2024 - 11:38am
Will a chase for long-lost alien artifacts turn into an intergalactic arms race on Star Trek: Discovery? But more importantly, Grudge is back for season 5, episode 2.
Categories: Astronomy

'Star Trek: Discovery' opens its 5th and final season in unremarkable fashion (Red Directive recap)

Space.com - Thu, 04/04/2024 - 11:29am
It's the fifth and final time around for "Star Trek: Discovery" and the single biggest question every sci-fan will be asking themselves is, will this season actually be any good.
Categories: Astronomy

The James Webb Space Telescope has solved a lot of puzzles, and created a few more

Space.com - Thu, 04/04/2024 - 11:00am
Hosted by Neil deGrasse Tyson, the 2024 Isaac Asimov Memorial Debate surrounded the James Webb Space Telescope's scientific revolution.
Categories: Astronomy

NASA's James Webb Space Telescope mission — Live updates

Space.com - Thu, 04/04/2024 - 10:31am
Read the latest news about NASA's James Webb Space Telescope.
Categories: Astronomy

How Rats Took Over North America

Scientific American.com - Thu, 04/04/2024 - 10:30am

Rat remains from shipwrecks and dig sites show how two rodent species duked it out in eastern North America

Categories: Astronomy

Bisexual women expect to have an orgasm with women more than with men

New Scientist Space - Cosmology - Thu, 04/04/2024 - 10:00am
When asked to imagine a hypothetical sexual encounter, bisexual women anticipated that they would be more likely to orgasm with another woman than with a man
Categories: Astronomy

Bisexual women expect to have an orgasm with women more than with men

New Scientist Space - Space Headlines - Thu, 04/04/2024 - 10:00am
When asked to imagine a hypothetical sexual encounter, bisexual women anticipated that they would be more likely to orgasm with another woman than with a man
Categories: Astronomy

Electric vehicles have lowered San Francisco's carbon footprint

New Scientist Space - Cosmology - Thu, 04/04/2024 - 9:00am
A network of sensors stretching from San Francisco to Sonoma county’s vineyards shows that electric vehicles have helped lower carbon emissions by almost 2 per cent per year within the Bay Area
Categories: Astronomy