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Bacteria could survive a journey between the Earth and Mars, ISS study shows – CNET

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


JAXA/NASA

Space isn’t kind to the human body, but microscopic organisms like fungi and bacteria seem to do OK when exposed to the void. In fact, some fungi that have made a home on the International Space Station 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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BREAKING | 24 new cases of COVID-19 in Niagara – Newstalk 610 CKTB (iHeartRadio)

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Niagara Region Public Health are reporting 24 new cases of COVID-19 in the region.

This is the highest single day increase of cases since June 3rd, which saw 40 new cases in the region.

Currently, Niagara has 77 active cases of the virus, and five active outbreaks.

To see the full details from Niagara Region Public Health, click here.

Ontario reported 491 new cases today.

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A physicist says new math proves paradox-free time travel is possible – SlashGear

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Time travel has been the staple science fiction books and movies for many years. Most who have read or watched content focusing on time travel knows about the paradox issue. Perhaps the best example is the 80s classic “Back to the Future,” where Marty accidentally prevents his parents from meeting and has to fix his error before he’s wiped out of existence.

Time travel is something that scientists and physicists have considered for many years. A physics student named Germain Tobar from the University of Queensland in Australia says that he has figured out the math that would make time travel viable without paradoxes. According to Tobar, classical dynamics says if you know the state of the system at a particular time, it can tell you the entire history of the system.

His calculations suggest that space-time may be able to adapt itself to avoid paradoxes. One example is a time traveler who journeys into the past to stop a disease from spreading. If the mission were successful, there would’ve been no disease for the time traveler to go back and try and prevent. Tobar suggests that the disease would still spread in some other way, through different route or method, removing the paradox.

He says whatever the time traveler did, the disease wouldn’t be stopped. Tobar’s work is highly complicated but is essentially looking at deterministic processes on an arbitrary number of regions in the space-time continuum. It’s demonstrating how closed timelike curves, which Einstein predicted, can fit in with the rules of free will and classical physics.

Tobar’s research supervisor is physicist Fabio Costa from the University of Queensland. Costa says that the “maths checks out,” further noting that the results are the stuff of science fiction. The new math suggests that time travelers can do what they want, and paradoxes are not possible. Costa says that events will always adjust themselves to avoid any inconsistency.

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We May Finally Know What Life on Earth Breathed Before There Was Oxygen – ScienceAlert

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Billions of years ago, long before oxygen was readily available, the notorious poison arsenic could have been the compound that breathed new life into our planet.

In Chile’s Atacama Desert, in a place called Laguna La Brava, scientists have been studying a purple ribbon of photosynthetic microbes living in a hypersaline lake that’s permanently free of oxygen.

“I have been working with microbial mats for about 35 years or so,” says geoscientist Pieter Visscher from the University of Connecticut.

“This is the only system on Earth where I could find a microbial mat that worked absolutely in the absence of oxygen.”

Microbial mats, which fossilise into stromatolites, have been abundant on Earth for at least 3.5 billion years, and yet for the first billion years of their existence, there was no oxygen for photosynthesis.

How these life forms survived in such extreme conditions is still unknown, but examining stromatolites and extremophiles living today, researchers have figured out a handful of possibilities. 

While iron, sulphur, and hydrogen have long been proposed as possible replacements for oxygen, it wasn’t until the discovery of ‘arsenotrophy‘ in California’s hypersaline Searles Lake and Mono Lake that arsenic also became a contender.

Since then, stromatolites from the Tumbiana Formation in Western Australia have revealed that trapping light and arsenic was once a valid mode of photosynthesis in the Precambrian. The same couldn’t be said of iron or sulphur.

Just last year, researchers discovered an abundant life form in the Pacific Ocean that also breathes arsenic. 

Even the La Brava life forms closely resemble a purple sulphur bacterium called Ectothiorhodospira sp., which was recently found in an arsenic-rich lake in Nevada and which appears to photosynthesise by oxidising the compound arsenite into a different form -arsenate.

While more research needs to verify whether the La Brava microbes also metabolise arsenite, initial research found the rushing water surrounding these mats is heavily laden with hydrogen sulphide and arsenic.

If the authors are right and the La Brava microbes are indeed ‘breathing’ arsenic, these life forms would be the first to do so in a permanently and completely oxygen-free microbial mat, similar to what we would expect in Precambrian environments.

As such, its mats are a great model for understanding some of the possible earliest life forms on our planet. 

While genomic research suggests the La Brava mats have the tools to metabolise arsenic and sulphur, the authors say its arsenate reduction appears to be more effective than its sulfate reduction.

Regardless, they say there’s strong evidence that both pathways exist, and these would have been enough to support extensive microbial mats in the early days of life on Earth.

If the team is right, then we might need to expand our search for life forms elsewhere.

“In looking for evidence of life on Mars, [scientists] will be looking at iron and probably they should be looking at arsenic also,” says Visscher.

It really is so much more than just a poison.

The study was published in Communications Earth and Environment

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