Connect with us


Why some scientists believe life may have started on Mars – Salon



On February 18, NASA’s Perseverance rover will parachute through thin Martian air, marking a new era in red planet exploration. Landing on the Jezero Crater, which is located north of the Martian equator, will be no easy feat. Only about 40 percent of the missions ever sent to Mars succeed, according to NASA. If it does, Perseverance could drastically change the way we think about extraterrestrial life. That’s because scientists believe Jezero, a 28 mile-wide impact crater that used to be a lake, is an ideal place to look for evidence of ancient microbial life on Mars.

Once it lands, Perseverance will collect and store Martian rock and soil samples, which will eventually be returned to Earth. This is known as a “sample-return mission,” an extremely rare type of space exploration mission due to its expense. (Indeed, there has never been a sample return mission from another planet.) And once Martian soil is returned to Earth in a decade, scientists will set about studying the material to figure out if there was ever ancient life on Mars. 


Yet some scientists believe that these samples could answer an even bigger question: Did life on Earth originate on Mars?

Though the idea that life started on Mars before migrating on Earth sounds like some far-fetched sci-fi premise, many renowned scientists take the theory seriously. The general idea of life starting elsewhere in space before migrating here has a name, too: Panspermia. It’s the hypothesis that life exists elsewhere in the universe, and is distributed by asteroids and other space debris.

To be clear, the notion of life on Earth originating on Mars isn’t a dominant theory in the scientific community, but it does appear to be catching on. And scientists like Gary Ruvkun, a professor of genetics at Harvard Medical School, say that it does sound “obvious, in a way.”


The evidence starts with how space debris moved around in the young solar system. Indeed, we have evidence of an exchange of rocks from Mars to Earth. Martian meteorites have been found in Antarctica and across the world — an estimated 159, according to the International Meteorite Collectors Association.

“You can assign them to Mars based on the gaseous inclusions that they have, that are sort of the equivalent of the gases that were shown by the Viking spacecraft” to exist in Mars’ atmosphere, Ruvkun said. In other words, small bubbles of air in these rocks reveal that they were forged in the Martian air. “So, there is exchange between Mars and Earth — probably more often going from Mars to Earth because it goes ‘downhill,’ going to Mars is ‘uphill,’ gravitationally-speaking.”

But for Ruvkun, whose area of expertise is genomics, it’s the timing of cellular life that he believes makes a strong case that life on Earth came from somewhere else — perhaps Mars, or perhaps Mars vis-a-vis another planet.


Ruvkun noted that our genomes reveal the history of life, and provide clues about the ancestors that preceded us by millions or even billions of years. “In our genomes, you can kind of see the history, right?” he said. “There’s the RNA world that predated the DNA world and it’s very well supported by all kinds of current biology; so, we know the steps that evolution took in order to get to where we are now.”

Thanks to the advancement of genomics, the understanding of LUCA (the Last Universal Common Ancestor) — meaning the organism from which all life on Earth evolved from — has greatly advanced. By studying the genetics of all organisms on Earth, scientists have a very good sense of what the single-celled ancestor of every living thing (on Earth) looked like. They also know the timeline: all modern life forms descend from a single-celled organism that lived about 3.9 billion years ago, only 200 million years after the first appearance of liquid water. In the grand scheme of the universe, that’s not that long.


And the last universal common ancestor was fairly complicated as far as organisms go. That leaves two possibilities, Ruvkun says. “Either evolution to full-on modern genomes is really easy, or the reason you see it so fast was that we just ‘caught’ life, it didn’t actually start here.” He adds, “I like the idea that we just caught it and that’s why it’s so fast, but I’m an outlier.”

If that’s the case, then Erik Asphaug, is a professor of planetary science at the University of Arizona, is also an outlier. Asphaug said that what we know about the oldest rocks on Earth — which have chemical evidence of carbon isotopes, tracing back to nearly 4 billion years ago — tell us that life started “started forming on Earth almost as soon as it was possible for it to happen.”

If that’s the case, it makes for an interesting precedent. “Let’s say you expect life to be flourishing whenever a planet cools down to the point where it can start to have liquid water,” Asphaug said. “But just looking at our own solar system, what planet was likely to be habitable first? Almost certainly Mars.”


This is because, Asphaug said, Mars formed before Earth did. Early in Martian history when Mars was cooling down, Mars would have had a “hospitable” environment before Earth.

“If life was going to start anywhere it might start first on Mars,” Asphaug said. “We don’t know what the requirement is — you know, if it required something super special like the existence of a moon or some factors that are unique to the Earth — but just in terms of what place had liquid water first, that would have been Mars.”

An intriguing and convincing piece of evidence relates to how material moved between the two neighboring planets. Indeed, the further you go back in time, the bigger the collisions of rocks between Mars and Earth, Asphaug said. These impact events could have been huge “mountain-sized blocks of Mars” that were launched into space. Such massive asteroids could serve as a home for a hardy microorganism.


“When you collide back into a planet, some fraction of that mountain-sized mass is going to survive as debris on the surface,” he said. “It’s taken a while for modeling to show that you can have a relatively intact survival of what we call ‘ballistic panspermia’ — firing a bullet into one planet, knocking bits off, and having it end up on another planet. But it’s feasible, we think it happens, and the trajectory would tend to go from Mars to the Earth, much more likely than from Earth to Mars.”

Asphaug added that surviving the trip, given the mass of the vehicle for the microorganisms, wouldn’t be a problem — and neither would surviving on a new, hospitable planet.

“Any early life form would be resistant to what’s going on at the tail end of planet formation,” he said. “Any organism that’s going to be existing has to be used to the horrific bombardment of impacts, even apart from this, swapping from planet to planet.”

In other words, early microbial life would have been fine with harsh environments and long periods of dormancy. 


Harvard professor Avi Loeb told Salon via email that one of the Martian rocks found on Earth, ALH 84001, “was not heated along its journey to more than 40 degrees Celsius and could have carried life.”

All three scientists believe that Perseverance might be able to add credibility to the theory of panspermia.

“If you were to go and find remnants of life on Mars, which we hope to do with Perseverance rover and these other Martian adventures, I would be personally surprised if they were not connected at the hip to terrestrial life,” Asphaug said.

Ruvkun said he hopes to be one of the scientists to look for DNA when the sample from Mars hopefully, eventually, returns. 


“Launching something from Mars is a seriously difficult thing,” he said. 

But what would this mean for human beings, and our existential understanding of who we are and where we came from?

“In that case, we might all be Martians,” Loeb said. He joked that the self-help book “Men are from Mars, Women are from Venus” may have been more right than we know.

Or perhaps, as Ruvkun believes, we’re from a different solar system, and life is just scattering across the universe.


“To me the idea that it all started on Earth, and every single solar system has their own little evolution of life happening, and they’re all independent — it just seems kind of dumb,” Ruvkun said. “It’s so much more explanatory to say ‘no, it’s spreading, it’s spreading all across the universe, and we caught it too, it didn’t start here,” he added. “And in this moment during the pandemic — what a great moment to pitch the idea. Maybe people will finally believe it.”

Let’s block ads! (Why?)

Source link

Continue Reading


Sudbury native aiding NASA rover's hunt for life on Mars – The Sudbury Star



Raymond Francis hopes to become a Canadian Space Agency astronaut

Article content

The NASA rover mission scouring Mars for ancient life has a connection to Sudbury.

Raymond Francis, who graduated from Western University in 2014 with a PhD in computer engineering and planetary science, is an engineer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

Francis, whose aspirations include becoming a Canadian Space Agency astronaut — maybe even one of the first on the red planet — is part of the team helping guide the rover Perseverance through Mars’s Jezero crater, which scientists say was a lake 3.5 billion years ago.

It is the first time a Mars rover will be collecting rock and soil, which will be stored until they can be returned to Earth.

“If ever there was life on Mars, this is the time it may well have arisen,” Francis said. “We would be elated if we found signs of ancient life on Mars. No one is expecting current life, but we explicitly have a goal of finding signs of life.”


Story continues below

This advertisement has not loaded yet, but your article continues below.

Article content

Jezero, which means lake in Slavic languages, is named after a settlement.

“The lake was there for a long time, because the river flowing into had enough time to build up a delta, the kind you find at the mouth of the Mississippi or the Nile,” Francis said.

Sudbury native Raymond Francis, who graduated from Western in 2014 with a PhD in computer engineering and planetary science, and will be helping guide the rover Perseverance during its time on Mars.
Sudbury native Raymond Francis, who graduated from Western in 2014 with a PhD in computer engineering and planetary science, and will be helping guide the rover Perseverance during its time on Mars. SunMedia

“Deltas are also a good place to preserve signs of life, because they are constantly setting down new sediment. If there are living things in that lake, they can get buried in the sediment and preserved.”

But even if they don’t find life, the research into Mars’s environment, history and evolution would be incredibly valuable, he said.

“Any lake like this on Earth 3.5 billion years ago was probably full of microbes,” Francis said. “If this one on Mars was not, it tells us something about the difference between these two planets, regardless of life.”

While noisy and chaotic, Perseverance’s landing last Thursday — NASA shared video online — “worked out almost perfectly,” he said.

“People have put a lot of their life into this for the last decade and a lot of things had to go right for that landing to succeed …,” Francis said. “(At) each critical juncture, you could see people getting more hopeful.”

Now that Perseverance has landed, Francis’s work begins.

As science engineering liaison, he helps co-ordinate discussions of what the science team wants to do.

“They might be what observations to make, which experiments to run, where to drive the rover to make our next studies,” he said.


Story continues below

This advertisement has not loaded yet, but your article continues below.

Article content

The rover is “greatly improved” from its predecessor, Curiosity.

“It looks a lot like Curiosity rover, but it is not,” Francis said. “We have greatly improved capabilities and our autonomous driving system is much improved. We’ll be able to drive farther and faster.”

Francis also be part of operating its artificial intelligence system.

“I’m am going to have a role in deploying that software and making sure it gives us good science data,” he said.

Francis also runs a “supercam,” or laser geochemical spectrometer, he said.

Their work is being done on “Mars time,” where a day last 24 hours and 38 minutes and scientists will give up regular sleep cycles to use every second.

“The rover works best during the day on Mars, so we can spend less energy on heating because the sun is up and we can easily take pictures,” he said.

Rock and other samples collected by the rover will be retrieved, he said, likely in two missions in the early 2030s: one to land, pick up samples and lift them into orbit; another to carry them from Mars to Earth.

In earlier interviews, Francis said Sudbury and Science North helped shape his interest in science and space.

Francis told Tilbury District High School students in southern Ontario a few years ago about an encounter that changed his life.

“Probably the first time that happened to me was when I was … [in] first grade,” Francis said. “I grew up in Sudbury and there was a place there called Science North, a public science centre. And they had Bob Thirsk – a Canadian astronaut … and he came by with an American astronaut who had already flown. And they gave this presentation about ‘look, this is what it’s like to operate a space shuttle.’”


Story continues below

This advertisement has not loaded yet, but your article continues below.

Article content

“I still have the little poster he signed,” Francis added.

Thirsk would later become the first Canadian to fly at length in the International Space Station, in 2009.

Earlier this year, he told Quirks & Quarks, a science show on CBC Radio, that living in Sudbury in some ways helped prepare him for this Mars mission.

“You’re from Sudbury, which is a big mining town,” Quirks & Quarks asked. “And after building a career in robotics and space science, you’ve been led back to rocks. They’re just rocks on another world.”

“That’s right,” Francis replied. “And honestly, during my PhD studies in how to teach computers to look at rocks, I spent some time up in Sudbury looking at those. The mines in Sudbury are the results of an ancient impact crater that’s not quite as old as Jezero, but the impact geology is a very good analogue for the types of large scale impact sites we find in craters on Mars.

“So going home to Sudbury was actually a very useful thing for getting prepared for these kinds of studies on Mars.

Twitter: @SudburyStar


Postmedia is committed to maintaining a lively but civil forum for discussion and encourage all readers to share their views on our articles. Comments may take up to an hour for moderation before appearing on the site. We ask you to keep your comments relevant and respectful. We have enabled email notifications—you will now receive an email if you receive a reply to your comment, there is an update to a comment thread you follow or if a user you follow comments. Visit our Community Guidelines for more information and details on how to adjust your email settings.

Let’s block ads! (Why?)

Source link

Continue Reading


Prairie fireball was comet fragment burning up in Earth's atmosphere –



The fireball that lit up the sky across the Prairies on Monday morning was a small piece of a comet that burned up in the atmosphere, researchers at the University of Alberta say.

“Using two observation sites, we were able to calculate both its trajectory and velocity, which tell us about the origin of the meteor and reveal that it was a piece of a comet,” Patrick Hill, post-doctoral fellow in the Department of Earth and Atmospheric Sciences, said in a news release Thursday.

“This chunk was largely made of dust and ice, burning up immediately without leaving anything to find on the ground — but instead giving us a spectacular flash.”

The flash, captured by dozens of doorbell cameras and dashcams, occurred at 6:23 a.m. local time as the debris streaked through the sky to a final point on its trajectory 120 kilometres north of Edmonton, the researchers said.

The flash was visible throughout Alberta and parts of Saskatchewan due to the unusually high altitude of the fireball, they said.

WATCH | Fireball flashes across the Prairie sky:

A fireball buzzed over the Prairies on Monday, temporarily piercing the dark of the early morning sky with a flash of blinding blue light. 0:48

The chunk, likely only tens of centimetres across in size, was travelling at more than 220,000 km/h when it entered the atmosphere, they said.

“This incredible speed and the orbit of the fireball tell us that the object came at us from way out at the edge of the solar system — telling us it was a comet, rather than a relatively slower rock coming from the asteroid belt,” Chris Herd, curator of the University of Alberta Meteorite Collection and science professor, said in the release.

“Comets are made up of dust and ice and are weaker than rocky objects, and hitting our atmosphere would have been like hitting a brick wall for something travelling at this speed,” Herd said.

‘This is an incredible mystery to have solved’

While rocky objects usually burn up between 15 to 20 kilometres above the ground, Monday’s fireball occurred at an altitude of 46 kilometres allowing the flash to be seen across a wide area.

“All meteoroids — objects that become meteors once they enter Earth’s atmosphere — enter at the same altitude and then start to burn up with friction,” Hill said.

“Sturdier, rocky meteoroids can sometimes survive to make it to the ground, but because this was going so fast and was made of weaker material, it flashed out much higher in the atmosphere and was visible from much farther away.”

The research team calculated the trajectory of the fireball by using dark-sky images captured at the Hesje Observatory at the Augustana Miquelon Lake Research Station and at Lakeland College’s observation station in Vermilion, Alta., the release said. 

“This is an incredible mystery to have solved,” Herd said. “We’re thrilled that we caught it on two of our cameras, which could give everyone who saw this amazing fireball a solution.”

Let’s block ads! (Why?)

Source link

Continue Reading


'Forward edge of human exploration': Victoria company helps design piece of NASA Mars rover – CTV Edmonton



When NASA’s six-wheeled Perseverance rover touched down on the red soil of Mars, ground control teams in California leapt to their feet in unbridled enthusiasm. But they weren’t the only ones bursting with joy.

North of the border on Vancouver Island, a team of mechanical engineers and metal workers were overwhelmed with their work landing on the red planet.

“A lot of the guys were watching the landing on their computers as it came down, going through the countdown. So, there was a lot of excitement,” said Ron Sivorot, Kennametal Inc. Langford Site business director.

Inside Kennametal Inc. in Greater Victoria, teams of metal workers and mechanical engineers design a variety of custom products for businesses around the world.

Last Thursday, however, was the first time a partnership had taken the Vancouver Island business into orbit.

In 2014 the company began a partnership with NASA’s jet propulsion laboratory to help design and build a drill bit capable of tearing into the harsh and unknown soil of Mars.

“We specifically made a tooth blank for a core bit drill,” said Sivorot. “So basically, that is the business end of the drill that basically drills into Mars.”

The company has a specific skillset with the material tungsten carbide.

It’s an incredibly hard metal known for its use in harsh climates.

Staff at the Langford operation helped create a blank drill bit tip which NASA then put the final touches on before mounting to the car-sized rover.

Perseverance touched down in dramatic fashion on Mars last week and almost immediately began its work of taking core samples.

NASA hopes that drilling into the ground of Mars could uncover galactic mysterious about the planet and possibly uncover life on another planet.

Commander Chris Hadfield is no stranger to Canadian contributions to space exploration.

The Toronto-based astronaut was the first Canadian to walk in space and has served as the commander of the International Space Station.

He says each time Canada is represented in the cosmos, it dares us all to dream bigger.

“There is a great sense of contributing to something important that is bigger than yourself,” said Col. Hadfield from his Toronto home.

“For the folks at Kennametal, they are doing a great job, they make a great product. Their tungsten carbide is twice as hard as steel, but that little thing they work on, that they take daily pride in, is now right on the very forward edge of human exploration,” he said.

Over the next two years, the rover will use its two-meter arm to drill down and collect rock samples containing possible signs of bygone microscopic life.

Three to four dozen chalk-size samples will be sealed in tubes and set aside to be retrieved eventually by another rover and brought homeward by another rocket ship.

The goal is to get them back to Earth as early as 2031. 

Let’s block ads! (Why?)

Source link

Continue Reading