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Bacteria on the ISS survive the perils of space for three years – CNET

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Kimiya Yui helped set up the exposure experiment module on the International Space Station back in 2015.


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Space is not kind to humans. Even inside the International Space Station, scientists have shown prolonged flight can lead to some negative health effects and mess with DNA. But if you’re a microscopic organism, things can be a little different.

In fact, some fungi that have made a home on the ISS even find the conditions preferable — they can feed on the extra radiation. This kind of evidence has led some scientists to suggest microscopic organisms might be ejected into space and perhaps they could move between planets, seeding life across the cosmos.

It’s a controversial concept known as “panspermia,” and it’s been championed by some unusual characters in the past as an alternative theory for how life began. 

In a new study, published in the journal Frontiers in Microbiology, Japanese researchers sent densely-packed balls of bacteria to the International Space Station and stuck them on the outside of the lab, where they were exposed to the harsh, cold and radiation-heavy vacuum of space.

The experiment, known as Tanpopo, has been running since 2015. In Japanese, tanpopo means dandelion, and the experiment is so named because the dandelion spreads its seeds via the wind. Could the same thing happen in space, with radiation-resistant bacteria? That was the question Akihiko Yamagishi, an astrobiologist at the Tokyo University of Pharmacy and Life Science, set out to answer all the way back in 2007, when his experiments were first accepted as a candidate experiment on the ISS.

Yamagishi doesn’t see himself as a proponent of panspermia but wanted to see if there were ways microbes might be able to survive a trip from Earth to somewhere else in the cosmos.

When the Japanese space agency’s Experiment Handrail Attachment Mechanism was installed on the ISS in 2015, Yamagishi and his team finally had a chance to conduct their research. By placing colonies of the radiation-resistant Deinococcus into wells and drying the suspensions in the air over and over again, they were able to create “pellets” of bacteria. In 2015, these pellets were installed on the space station in plates aboard the ExHAM.

Concurrent experiments were designed to look at the pellets after one, two and three years. The experiment officially concluded in 2018 and since then Yamagishi’s team have been analyzing the data.

The major finding shows these pellets can survive damage from UV radiation in space a lot better when the pellets were thicker. When the pellets were around half a millimeter thick, the outer layers of bacteria began to break down, but those in the center survived. Yamagishi and his team reason these thicker pellets of bacteria, exposed to interplanetary space, might survive from two to eight years — in theory, long enough to be ejected from Earth and make it to one of our closest neighbours.

“The results suggest radioresistant Deinococcus could survive during the travel from Earth to Mars and vice versa, which is several months or years in the shortest orbit,” said Yamagishi.    

Bacterial astronauts

Panspermia proponents suggest some bacteria may be able to take interplanetary trips trapped inside meteorites and micrometeorites, a theory known as lithopanspermia. Yamagishi’s work took a look at a different theory — that these ball-like colonies of bacteria might protect themselves. This is known as massapanspermia.

But there are a number of lingering issues. A straight shot from Earth to Mars isn’t exactly the most likely route microbial adventurers might take.   

“In theory the time could be months or years, if you hitched a ride aboard the Mars Perseverance rocket,” says Brendan Burns, an astrobiologist at the University of New South Wales not affiliated with the study. “But in terms of ‘natural’ journeys the likelihood of an object ejected from Earth and hitting Mars in a short space of time is slim.”

While Yamagishi’s research does demonstrate the ability for bacteria to survive space for extended periods of time, Burns notes meteorites can have a flight time of more than 10 million years before they jump planets. 

And there’s a pretty big problem to overcome if you’re microscopic and trying to relocate from planet to planet. First, you have to be ejected from your home planet without dying, survive the long (really long) journey across space and then make it through an atmospheric re-entry. Even NASA robots are terrified of entering the atmosphere of Mars

Yamagishi concurs. “Very little is known about entry and ejection,” he says.

But let’s say Deinococcus got through all of that, what happens when the bacteria get to their new home? The situation is likely dire for an Earth transplant, used to a world of running water and protected by a thick atmosphere.

“Even if a given lifeform could survive interplanetary travel, the conditions of where it ends up must be just right for it to take off again,” says Burns. He notes the microbes would need to look for nutrients and would need to be hardy enough to withstand any differences in the atmosphere. So while the panspermia hypothesis remains possible, Burns says, “the jury is still very much out.”

Yamagishi’s team and the Tanpopo mission will continue exposure experiments “with different species in different conditions” and hope to see how general the process of massapanspermia may be.

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NASA Publishes Artemis Plan to Land First Woman, Next Man on Moon in 2024 – Stockhouse

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WASHINGTON , Sept. 21, 2020 /PRNewswire/ — Following a series of critical contract awards and hardware milestones, NASA has shared an update on its Artemis program, including the latest Phase 1 plans to land the first woman and the next man on the surface of the Moon in 2024.

In the 18 months since NASA accepted a bold challenge to accelerate its exploration plans by more than four years and establish sustainable exploration by the end of the decade, the agency has continued to gain momentum toward sending humans to the Moon again for the first time since the last Apollo lunar mission in 1972.

“With bipartisan support from Congress, our 21st century push to the Moon is well within America’s reach,” said NASA Administrator Jim Bridenstine . “As we’ve solidified more of our exploration plans in recent months, we’ve continued to refine our budget and architecture. We’re going back to the Moon for scientific discovery, economic benefits, and inspiration for a new a generation of explorers. As we build up a sustainable presence, we’re also building momentum toward those first human steps on the Red Planet.”

In its formal plan, NASA captures Artemis progress to date, identifying the key science, technology and human missions, as well as the commercial and international partnerships that will ensure we continue to lead in exploration and achieve our ambitious goal to land astronauts on the Moon.

The agency’s powerful new rocket, the Space Launch System (SLS), and the Orion spacecraft are closer than ever to their first integrated launch. The spacecraft is complete while the core stage and its attached four engines are undergoing a final series of tests that will culminate in a critical hot fire test this fall.

Early Artemis Missions

Following a successful hot fire test, the core stage will be shipped to the agency’s Kennedy Space Center in Florida for integration with the spacecraft. NASA will launch an SLS and an Orion together on two flight tests around the Moon to check performance, life support, and communication capabilities. The first mission – known as Artemis I – is on track for 2021 without astronauts, and Artemis II will fly with crew in 2023.

In the Phase 1 plan, NASA notes additional details about conducting a new test during the Artemis II mission – a proximity operations demonstration. Shortly after Orion separates from the interim cryogenic propulsion stage, astronauts will manually pilot Orion as they approach and back away from the stage. This demonstration will assess Orion’s handling qualities and related hardware and software to provide performance data and operational experience that cannot be readily gained on the ground in preparation for rendezvous, proximity operations, and docking, as well as undocking operations in lunar orbit beginning on Artemis III.

While preparing for and carrying out these flight test missions, NASA already will be back on the Moon robotically – using commercial delivery services to send dozens of new science investigations and technology demonstrations to the Moon twice per year beginning in 2021.

In 2024, Artemis III will be humanity’s return to the surface of the Moon. After launching on SLS, astronauts will travel about 240,000 miles to lunar orbit aboard Orion, at which point they will directly board one of the new commercial human landing systems , or dock to the Gateway to inspect it and gather supplies before boarding the landing system for their expedition to the surface.

Wearing modern spacesuits that allow for greater flexibility and movement than those of their Apollo predecessors, astronauts will collect samples and conduct a range of science experiments over the course of nearly seven days. Using the lander, they will return to lunar orbit before ultimately heading home to Earth aboard Orion.

Work is progressing rapidly on the Gateway. NASA will integrate the first two components to launch – the power and propulsion element and the habitation and logistics outpost – in 2023. This foundation for the Gateway will be able to operate autonomously, conducting remote science experiments when astronauts are not aboard. NASA has selected the first two science instrument suites to conduct space weather investigations in lunar orbit before crew visits.

While NASA has not made a final decision to use the Gateway for Artemis III, Artemis IV and beyond will send crew aboard Orion to dock to the Gateway, where two crew members can stay aboard the spaceship in orbit while two go to the surface. Over time, the outpost will evolve, with new modules added by international partners, allowing crew members to conduct increasingly longer lunar missions.

As detailed in the agency’s concept for surface sustainability earlier this year, an incremental buildup of infrastructure on the surface will follow later this decade, allowing for longer surface expeditions with more crew. That concept calls for an Artemis Base Camp that would include new rovers, power systems, habitats, and more on the surface for long-term exploration of the Moon.

Throughout the Artemis program, robots and humans will search for, and potentially extract, resources such as water that can be converted into other usable resources, including oxygen and fuel. By fine-tuning precision landing technologies as well as developing new mobility capabilities, astronauts will travel farther distances and explore new regions of the Moon.

Learn more about NASA’s Artemis program at:

www.nasa.gov/artemis

Cision View original content to download multimedia: http://www.prnewswire.com/news-releases/nasa-publishes-artemis-plan-to-land-first-woman-next-man-on-moon-in-2024-301135059.html

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Arctic ice melt doesn't boost sea levels, so do we care? – FRANCE 24

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Paris (AFP)

US government scientists reported Monday that the Arctic Ocean’s floating ice cover has shrivelled to its second lowest extent since satellite records began in 1979.

Until this month, only once in the last 42 years has Earth’s frozen skull cap covered less than four million square kilometres (1.5 million square miles).

The trend line is clear: sea ice extent has diminished 14 percent per decade over that period. The Arctic could see it’s first ice-free summer as early as 2035, researchers reported in Nature Climate Change last month.

But all that melting ice and snow does not directly boost sea levels any more than melted ice cubes make a glass of water overflow, which gives rise to an awkward question: who cares?

Granted, this would be bad news for polar bears, which are already on a glide path towards extinction, according to a recent study.

And yes, it would certainly mean a profound shift in the region’s marine ecosystems, from phytoplankton to whales.

But if our bottom-line concern is the impact on humanity, one might legitimately ask, “So what?”.

As it turns out, there are several reasons to be worried about the knock-on consequences of dwindling Arctic sea ice.

– Feedback loops –

Perhaps the most basic point to make, scientists say, is that a shrinking ice cap is not just a symptom of global warming, but a driver as well.

“Sea ice removal exposes dark ocean, which creates a powerful feedback mechanism,” Marco Tedesco, a geophysicist at Columbia University’s Earth Institute, told AFP.

Freshly fallen snow reflects 80 percent of the Sun’s radiative force back into space.

But when that mirror-like surface is replaced by deep blue water, about the same percentage of Earth-heating energy is absorbed instead.

And we’re not talking about a postage stamp area here: the difference between the average ice cap minimum from 1979 to 1990 and the low point reported today — more than 3 million km2 — is twice the size of France, Germany and Spain combined.

The oceans have already soaked up 90 percent of the excess heat generated by manmade greenhouse gases, but at a terrible cost, including altered chemistry, massive marine heatwaves and dying coral reefs.

And at some point, scientists warn, that liquid heat sponge may simply become saturated.

– Altering ocean currents –

Earth’s complex climate system includes interlocking ocean currents driven by wind, tides and something called the thermohaline circulation, which is itself powered by changes in temperature (“thermo”) and salt concentration (“haline”).

Even small changes in this Great Ocean Conveyor Belt — which moves between poles and across all three major oceans — can have devastating climate impacts.

Nearly 13,000 years ago, for example, as Earth was transitioning out of an ice age into the interglacial period that allowed our species to thrive, global temperatures abruptly plunged several degrees Celsius. They jumped back up again about 1,000 years later.

Geological evidence suggests a slowdown in the thermohaline circulation caused by a massive and rapid influx of cold, fresh water from the Artic region was partly to blame.

“The fresh water from melting sea ice and grounded ice in Greenland perturbs and weakens the Gulf Stream,” part of the conveyor belt flowing in the Atlantic, said Xavier Fettweis, a research associate at the University of Liege in Belgium.

“This is what allows western Europe to have a temperate climate compared to the same latitude in North America.”

The massive ice sheet atop Greenland’s land mass saw a net loss of more than half-a-trillion tonnes last year, all of it flowing into the sea.

Unlike sea ice, which doesn’t increase sea levels when it melts, runoff from Greenland does.

That record amount was due in part to warmer air temperatures, which have risen twice as fast in the Arctic as for the planet as a whole.

But it was also caused by a change in weather patterns, notably an increase in sunny summer days.

“Some studies suggest that this increase in anticyclonic conditions in the Arctic in summer results in part from the minimum sea ice extent,” Fettweis told AFP.

– Bears on thin ice –

The current trajectory of climate change and the advent of ice-free summers — defined by the UN’s IPCC climate science panel as under one million km2 — would indeed starve polar bears into extinction by century’s end, according to a July study in Nature.

“Human-caused global warming means that polar bears have less and less sea ice to hunt on in the summer months,” Steven Amstrup, lead author of the study and chief scientist of Polar Bears International, told AFP.

“The ultimate trajectory of polar bears with unabated greenhouse gas emissions is disappearance.”

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Arctic sea ice shrinks to 2nd lowest level in 4 decades – CBC.ca

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Warming in the Arctic shrank the ice covering the polar ocean this year to its second-lowest extent in four decades, scientists announced Monday, yet another sign of how climate change is rapidly transforming the region.

Satellites recorded this year’s sea ice minimum at 3.74 million square kilometres on Sept. 15, only the second time the ice has been measured below 4 million square kilometres in 40 years of record keeping, said researchers at the National Snow and Ice Data Center

“It’s fairly devastating that we’ve had such consistently low sea ice. But unfortunately, it’s not surprising,” said Twila Moon, a glaciologist at the research centre in Boulder, Colorado.

The record low of 3.41 million square kilometres, reached in 2012 after a late-season cyclonic storm broke up the remaining ice, is not much below what researchers see today.

This year’s decline was especially fast between Aug. 31 and Sept. 5, thanks to pulses of warm air coming off a heat wave in Siberia, according to the NSIDC. The rate of ice loss during those six days was faster than during any other year on record. Another team of scientists found in July that the Siberian heat wave would have been all but impossible without human-caused climate change.

As the Arctic sea ice vanishes, it leaves patches of dark water open. Those dark waters absorb solar radiation rather than reflecting it back out of the atmosphere, a process that amplifies warming and helps to explain why Arctic temperatures have risen more than twice as fast as the rest of the world over the last 30 years.

Arctic sea ice at the North Pole is seen from the German icebreaker RV Polarstern, on Aug. 19, 2020. The voyage made an unplanned detour because of lighter-than-usual sea ice conditions. (Markus Rex/Alfred Wegener Institute via AP)

The loss of sea ice also threatens Arctic wildlife, from polar bears and seals to plankton and algae, said Tom Foreman, a polar wildlife expert and Arctic guide.

“The numbers that we’re getting in terms of extent of sea ice decrease each year put us pretty much on red alert in terms of the level of worry that we have, our concern for the stability of this environment,” Foreman said.

The same warming that is opening summertime Arctic waters is also eating away at the ice sheets covering Arctic lands in Canada and Greenland. The faster those ice sheets melt into surrounding ocean, the faster sea levels will rise worldwide.

Given that a warmer Arctic could impact weather patterns worldwide, Moon said the world should not wait for another new record sea ice low before taking action to limit climate change.

“We should work very hard to make differences in our emissions of polluting gases so that we do not see so many records created in the future,” Moon said.

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