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Rare molecule in Venus’ atmosphere could be sign of life

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Sept. 14 (UPI) — Venus is one of the most inhospitable places in the solar system, but astronomers have long speculated that microbes might be able to survive in the planet’s upper atmosphere, according to a study published Monday in the journal Nature Astronomy.

Now, scientists have confirmed the presence of phosphine molecules, featuring hydrogen and phosphorus, inside Venusian clouds — a possible signature of airborne, extra-terrestrial life.

Astronomers initially discovered the molecule using Hawaii’s James Clerk Maxwell Telescope. After the discovery, researchers used the Atacama Large Millimeter/submillimeter Array, in Chile, to gather additional observations.

Both observatories field images in the electromagnetic spectrum, measuring light with wavelengths longer than those of infrared waves or x-rays but shorter than the wavelengths of radio waves or microwaves.

“This was an experiment made out of pure curiosity, really — taking advantage of JCMT’s powerful technology, and thinking about future instruments,” lead researcher Jane Greaves said in a news release.

“I thought we’d just be able to rule out extreme scenarios, like the clouds being stuffed full of organisms,” said Greaves, a professor of astronomy at Cardiff University in Wales. When we got the first hints of phosphine in Venus’ spectrum, it was a shock!”

Greaves first discovered the phosphine signature while working as a visiting research professor at the University of Cambridge’s Institute of Astronomy.

Observations using ALMA failed to reveal the phosphine signature in great detail, but the observatory’s images did confirm the molecule’s presence in Venusian clouds.

“We found that both observatories had seen the same thing — faint absorption at the right wavelength to be phosphine gas, where the molecules are backlit by the warmer clouds below,” said Greaves.

On Earth, phosphine is produced by industrial processes, as well as by microbes that thrive in oxygen-poor environs.

Models designed to simulate Venus’ atmosphere helped scientists interpret the data collected by ALMA and JCMT. Their analysis suggests the gas is relatively scarce, comprising just twenty molecules in every billion.

Researchers ran models to see if natural causes — including sunlight, minerals drafted upwards from the surface, volcanoes or lightning — might explain the presence of the rare molecule in Venus’ upper atmosphere. The simulations showed natural causes can explain, at most, just one ten-thousandth of the amount of phosphine found by ALMA and JCMT.

If microbes are indeed responsible for the production of the phosphine found in Venusian clouds, they likely look much different than the microbes that make phosphine on Earth.

“Phosphine is very hard to make in the oxygen-rich, hydrogen-poor clouds of Venus and fairly easy to destroy,” said study co-author Paul Rimmer, researcher at Cambridge’s Cavendish Laboratory. “The presence of life is the only known explanation for the amount of phosphine inferred by observations.”

“Both of these facts lie at the edge of our knowledge: the observations could be caused by an unknown molecule, or could be caused by chemistry we’re not aware of,” Rimmer said. “Ultimately, the only way to find out what’s really happening is to send a mission into the clouds of Venus to take a sample of the droplets and look at them to see what’s inside.”

Akatsuki, the Japanese space agency probe that entered orbit around Venus nearly five years ago, is currently mapping a series of dark streaks where ultraviolet light is absorbed. Scientists have suggested that colonies of microbes might explain the unusual streaks.

NASA is also working on plans to send unscrewed spacecraft to Venus.

“Two of the next four candidate missions for NASA’s Discovery Program are focused on Venus, as is Europe’s EnVision mission, in which NASA is a partner,” the space agency said in a news release. “Venus also is a planetary destination we can reach with smaller missions.”

Even if Venus’ toxic clouds are slightly more forgiving than its scorching-hot surface, they’re not exactly inviting — because they’re quite acidic.

“On Earth, some microbes can cope with up to about 5 percent acid in their environment — but the clouds of Venus are almost entirely made of acid,” said co-author Clara Sousa Silva from MIT.

Scientists are currently conducting follow-up experiments to better understand how microbes might be able to shield themselves from the acidic environs inside protective cloud droplets.



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NASA’s OSIRIS-REx touches down on asteroid Bennu to nab sample

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Oct. 20 (UPI) — NASA’s OSIRIS-REx touched down on asteroid Bennu on Tuesday evening in a mission to scoop a sample of rocks and dirt.

The spacecraft — the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer — made soft contact with the asteroid at 6:12 p.m. EDT.

The historic “touch and go” event featured animation displaying OSIRIS-REx’s sample collection activities in real time. It takes time for real images of the touchdown to travel back to the Earth, so they won’t be released to the public until Wednesday.

The craft executed a series of maneuvers over the course of several hours before making soft contact with the surface of the asteroid to collect regolith, or rocks and dirt.

“It will be four and a half hours of anxiousness,” Beth Buck, OSIRIS-REx mission operations manager at Lockheed Martin Space, said in a news conference ahead of the event.

Buck made a comparison to the descent of a spacecraft on Mars, when there is typically “seven minutes of terror.”

The goal is to learn more about the solar system’s history and help “planetary defense” engineers with missions to protect earth from rogue asteroids. Bennu is believed to be a window into the solar system’s past since it’s a pristine, carbon-rich body carrying building blocks of both planets and life.

At around 1:50 p.m. EDT, the spacecraft left orbit around the asteroid before executing a series of burns to position itself over a sampling area nicknamed Nightingale.

Once in position, the craft began its approach to the asteroid at 5:50 p.m. EDT. It then spent about 15 seconds attempting to collect the regolith sample before backing away again.

The area, which is 52 feet in diameter, will make for a more demanding landing than expected, Kenneth Getzandanner, OSIRIS-REx flight dynamics manager at the NASA Goddard Space Flight Center in Maryland, said in the news conference.

The original mission called for a landing “zone” about 150% larger than Nightingale, at 82 feet, but that changed because Bennu was more rocky than expected.

The goal was to collect at least 1.7 ounces of fine-grained material, but the spacecraft can carry up to 4.4 pounds, Heather Enos, OSIRIS-REx deputy principal investigator at the University of Arizona said.

“I would love for that capsule to be completely full,” Enos said.

Though early images from the asteroid should hint at whether the mission succeeded, it will take engineers roughly 10 days to compare and analyze the mass before and after the maneuver to actually know how much dirt is inside the OSIRIS-REx.

If it failed, the spacecraft has enough fuel to attempt two more touch downs to collect material.

The spacecraft is expected to return to Earth, with the regolith sample from Bennu, in 2023.



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SpaceX scrubs Starlink launch until Thursday, if weather cooperates

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Oct. 21 (UPI) — Just three days after sending 60 more Starlink satellites into orbit, SpaceX is aiming to launch another batch of broadband satellites into space from Florida.

If the weather cooperates, Thursday’s launch will be SpaceX’s 15th Starlink mission.

Liftoff had been scheduled for 12:29 p.m. EDT Wednesday aboard a Falcon 9 rocket at Launch Complex 40 at Cape Canaveral Air Force Station, but controllers scrubbed the launch due to weather and rescheduled for 12:14 p.m. on Thursday.

With a launch Sunday, SpaceX increased the size of their Starlink constellation to nearly 800 satellites. The 15th mission will see another 60-odd satellites join the network.

“The goal of Starlink is to create a network that will help provide Internet services to those who are not yet connected, and to provide reliable and affordable Internet across the globe,” according to the Kennedy Space Center.

Weather for Wednesday’s planned launch had looked so-so and the Space Force’s 45th Weather Squadron predicted a 60 percent chance of favorable conditions.

“A mid-level inverted trough and associated easterly wave currently across the Bahamas will meander into the state over the next few days, bringing enhanced moisture, cloud cover, and instability with a higher coverage of showers and storms,” Space Force forecasters wrote.

They said Thursday’s forecast looks quite similar to Wednesday’s.

Earlier this month, SpaceX founder and CEO Elon Musk tweeted that Starlink’s constellation was big enough to begin beta-testing the Internet service system in both the United States and southern Canada.

SpaceX has already offered Starlink Internet services to emergency responders in wildfire-stricken areas of Washington State.

Washington’s Hoh tribe is also using the Internet service to provide their members online education and telehealth services.



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Chernobyl-level radiation harms bumblebee reproduction

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Oct. 21 (UPI) — Bees are more sensitive to radiation than scientists thought. Scientists found the reproduction rates of bumblebees declined significantly when exposed to Chernobyl-level radiation.

The research, published Wednesday in the journal Proceedings of the Royal Society B: Biological Sciences, suggests radiation in Ukraine’s Chernobyl Exclusion Zone could impair pollination services, triggering wider ecological consequences than previously estimated.

Humans are not allowed to live in the Chernobyl Exclusion Zone, the disaster area more directly impacted by the 1986 nuclear accident, the worst in history. However, the destroyed nuclear reactors are surrounded by forests that are populated by robust populations of birds, bears, bison, lynx, moose, wolves and more.

Efforts to gauge the effects of radiation contamination on insects have yielded mixed results in the past. While some studies have suggested insects are relatively radiation-resistant, others have demonstrated significant impairment.

When researchers exposed bumblebees in the lab to radiation dose of 100 µGyh-1, an amount approximating exposure inside the Chernobyl Exclusion Zone, reproduction rates among the bees dropped between 30 and 45 percent.

Researchers found a direct correlation between the size of the radiation dose and reproduction rate declines. Lower levels of radiation had a smaller effect, while larger doses yielded greater declines.

Scientists were surprised to find they were able to detect reproductive rate declines at very small levels of radiation exposure.

“Our research provides much needed understanding as to the effects of radiation in highly contaminated areas and this is the first research to underpin the international recommendation for the effects of radiation on bees,” lead study author Katherine Raines, environmental scientist at the University of Stirling in Scotland, said in a news release.



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