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Language: en
This speckled rock could be evidence of
ancient life on Mars. NASA called it
>> the clearest sign of life that we've
ever found.
>> Scientists say that traces of minerals
here could have been left behind by
ancient microbial life, maybe after a
meal about 3 and 1/2 billion years ago,
a time when primitive life was thriving
on Earth. Using tools on the
Perseverance Mars rover, scientists were
able to analyze the chemical makeup of
the rock. These teeny tiny dark specks,
NASA are calling them poppy seeds,
contain vivionite, an iron phosphate
mineral. And these areas, nicknamed
leopard spots, have vivvenite in the
dark ring. But in the center contain
greygite, an iron sulfide mineral. The
rock itself is also rich in organic
carbon, sulfur, oxidized iron, which is
rust, and phosphorus. And the
combination of these could have been a
rich energy source for microbes. But
there is a possibility the minerals in
this Martian rock were created by
non-living sources. To know for sure,
NASA will have to rule out all other
geological and chemical processes. And
to do that, researchers hope to one day
bring the samples from Mars to Earth to
study them more closely. So far, the
Perseverance rover has collected more
than 20 rock samples from the red
planet. Further analysis here on Earth
could bring us closer to answering one
of the most fundamental questions for
humanity. Are we alone? Believe it or
not, Mars was not always the cold,
inhospitable desert it is today. Several
billion years ago, there were flowing
rivers and lakes and even an atmosphere.
But over time, that atmosphere was lost,
transforming the climate and the red
planet's ability to sustain life on its
surface. But this area in the northern
hemisphere of Mars called Jezero Crater
has a telltale geographic signs of
water, fan-shaped deltas. Scientists
think rivers once spilled over the
crater wall and created a lake. Billions
of years ago, active rivers could have
deposited minerals and organic molecules
here. If Mars ever hosted microbial
life, this was the place to look. In
2021, the Perseverance Mars rover landed
in Jezero Crater. This crater has some
of the oldest rocks in the solar system.
And in 2024, the rover found this
speckled rock in an ancient river valley
called Naretva Valis in an area known as
the Bright Angel Rock Formation. But
notably, this rock outcrop is younger
than most of the other samples the rover
has taken, possibly suggesting that the
conditions for life could have lasted
longer than we thought. Since then,
scientists have been trying to
understand more about this area of Jezro
Crater and rule out all the possible
origins of these minerals. It's possible
these minerals did not come from
microbes, but researchers haven't been
able to find any evidence of that yet.
The rock doesn't show signs of extreme
heat or acidity that could have been
responsible for the compounds. Past
missions have found hints of life
before, like methane spikes, or hints of
organic molecules. But the standard of
proof for a major discovery like this,
life on another planet, is high. NASA
actually has a scale to assess
confidence, the cold scale, which stands
for confidence of life detection. And
this discovery sits at about a 2 out of
seven. So, has Perseverance definitely
found life on Mars? No, not yet. But
this discovery is one of the strongest
clues so far. It's of chemistry and
context that supports habitability. It
doesn't settle the question, but it
pushes us one step closer, reminding us
the story of life on Mars isn't totally
fictional. It may be written in stone.
[Music]
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