Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss
Is there life floating in the clouds of Venus?
1 view
Skip to first unread message
alexander koryagin
Oct 5, 2020, 6:31:13 AM10/5/20
to
Hi, All!
-----Beginning of the citation-----
Is there life floating in the clouds of Venus?
By Jonathan Amos
BBC Science Correspondent
It's an extraordinary possibility - the idea that living organisms are
floating in the clouds of Planet Venus.
But this is what astronomers are now considering after detecting a gas
in the atmosphere they can't explain.
That gas is phosphine - a molecule made up of one phosphorus atom and
three hydrogen atoms.
On Earth, phosphine is associated with life, with microbes living in the
guts of animals like penguins, or in oxygen-poor environments such as
swamps.
For sure, you can make it industrially, but there are no factories on
Venus; and there are certainly no penguins.
So why is this gas there, 50km up from the planet's surface? Prof Jane
Greaves, from Cardiff University, UK and colleagues are asking just this
question.
They've published a paper in the journal Nature Astronomy detailing
their observations of phosphine at Venus, as well as the investigations
they've made to try to show this molecule could have a natural,
non-biological origin.
But for the moment, they're stumped - as they tell the BBC's Sky At
Night programme, which has talked at length to the team. You can see the
show on BBC Four tonight (Monday) at 22:30 BST.
Given everything we know about Venus and the conditions that exist
there, no-one has yet been able to describe an abiotic pathway to
phosphine, not in the quantities that have been detected. This means a
life source deserves consideration.
"Through my whole career I have been interested in the search for life
elsewhere in the Universe, so I'm just blown away that this is even
possible," Prof Greaves said. "But, yes, we are genuinely encouraging
other people to tell us what we might have missed. Our paper and data
are open access; this is how science works."
What exactly has the team detected?
Prof Greaves' team first identified phosphine at Venus using the James
Clerk Maxwell Telescope in Hawaii, and then confirmed its presence using
the Atacama Large Millimeter/submillimeter Array in Chile.
Phosphine has a distinctive "absorption line" that these radio
telescopes discern at a wavelength of about 1mm. The gas is observed at
mid-latitudes on the planet at roughly 50-60km in altitude. The
concentration is small - making up only 10-20 parts in every billion
atmospheric molecules - but in this context, that's a lot.
Why is this so interesting?
Venus is not at the top of the list when thinking of life elsewhere in
our Solar System. Compared to Earth, it's a hellhole. With 96% of the
atmosphere made up of carbon dioxide, it has experienced a runaway
greenhouse effect. Surface temperatures are like those in a pizza oven -
over 400C.
Space probes that have landed on the planet have survived just minutes
before breaking down. And yet, go 50km up and it's actually
"shirtsleeves conditions". So, if there really is life on Venus, this is
exactly where we might expect to find it.
Why should we be sceptical?
The clouds. They're thick and they're mainly composed (75-95%) of
sulphuric acid, which is catastrophic for the cellular structures that
make up living organisms on Earth.
Dr William Bains, who's affiliated to the Massachusetts Institute of
Technology (MIT) in the US, is a biochemist on the team. He's studied
various combinations of different compounds expected to be on Venus;
he's examined whether volcanoes, lightning and even meteorites could
play a role in making PH3 - and all of the chemical reactions he's
investigated, he says, are 10,000 times too weak to produce the amount
of phosphine that's been observed.
To survive the sulphuric acid, Dr Bains believes, airborne Venusian
microbes would either have to use some unknown, radically different
biochemistry, or evolve a kind of armour.
"In principle, a more water-loving life could hide itself away inside a
protective shell of some sorts inside the sulphuric acid droplets," he
told Sky At Night. "We're talking bacteria surrounding themselves by
something tougher than Teflon and completely sealing themselves in. But
then how do they eat? How do they exchange gases? It's a real paradox."
What's been the reaction?
Cautious and intrigued. The team emphatically is not claiming to have
found life on Venus, only that the idea needs to be further explored as
scientists also hunt down any overlooked geological or abiotic chemical
pathways to phosphine.
Oxford University's Dr Colin Wilson worked on the European Space
Agency's Venus Express probe (2006-2014), and is a leading figure in the
development of a new mission concept called EnVision. He said Prof
Greaves' observations would spur a new wave of research at the planet.
"It's really exciting and will lead to new discoveries - even if the
original phosphine detection were to turn out to be a spectroscopic
misinterpretation, which I don't think it will. I think that life in
Venus' clouds today is so unlikely that we'll find other chemical
pathways of creating phosphine in the atmosphere - but we'll discover
lots of interesting things about Venus in this search," he told BBC News.
Prof Lewis Dartnell from the University of Westminster is similarly
cautious. He's an astrobiologist - someone who studies the possibilities
of life beyond Earth. He thinks Mars or the moons of Jupiter and Saturn
are a better bet to find life.
"If life can survive in the upper cloud-decks of Venus - that's very
illuminating, because it means maybe life is very common in our galaxy
as a whole. Maybe life doesn't need very Earth-like planets and could
survive on other, hellishly-hot, Venus-like planets across the Milky Way."
How can the question be resolved?
By sending a probe to investigate specifically the atmosphere of Venus.
The US space agency (Nasa) asked scientists recently to sketch the
design for a potential flagship mission in the 2030s. Flagships are the
most capable - and most expensive - ventures undertaken by Nasa. This
particular concept proposed an aerobot, or instrumented balloon, to
travel through the clouds of Venus.
"The Russians did this with their Vega balloon (in 1985)," said
team-member Prof Sara Seager from MIT. "It was coated with Teflon to
protect it from sulphuric acid and floated around for a couple of days,
making measurements.
"We could definitely go make some in-situ measurements. We could
concentrate the droplets and measure their properties. We could even
bring a microscope along and try to look for life itself."
https://www.bbc.com/news/science-environment-54133538
----- The end of the citation -----
Bye, All!
Alexander Koryagin
-----Beginning of the citation-----
Is there life floating in the clouds of Venus?
By Jonathan Amos
BBC Science Correspondent
It's an extraordinary possibility - the idea that living organisms are
floating in the clouds of Planet Venus.
But this is what astronomers are now considering after detecting a gas
in the atmosphere they can't explain.
That gas is phosphine - a molecule made up of one phosphorus atom and
three hydrogen atoms.
On Earth, phosphine is associated with life, with microbes living in the
guts of animals like penguins, or in oxygen-poor environments such as
swamps.
For sure, you can make it industrially, but there are no factories on
Venus; and there are certainly no penguins.
So why is this gas there, 50km up from the planet's surface? Prof Jane
Greaves, from Cardiff University, UK and colleagues are asking just this
question.
They've published a paper in the journal Nature Astronomy detailing
their observations of phosphine at Venus, as well as the investigations
they've made to try to show this molecule could have a natural,
non-biological origin.
But for the moment, they're stumped - as they tell the BBC's Sky At
Night programme, which has talked at length to the team. You can see the
show on BBC Four tonight (Monday) at 22:30 BST.
Given everything we know about Venus and the conditions that exist
there, no-one has yet been able to describe an abiotic pathway to
phosphine, not in the quantities that have been detected. This means a
life source deserves consideration.
"Through my whole career I have been interested in the search for life
elsewhere in the Universe, so I'm just blown away that this is even
possible," Prof Greaves said. "But, yes, we are genuinely encouraging
other people to tell us what we might have missed. Our paper and data
are open access; this is how science works."
What exactly has the team detected?
Prof Greaves' team first identified phosphine at Venus using the James
Clerk Maxwell Telescope in Hawaii, and then confirmed its presence using
the Atacama Large Millimeter/submillimeter Array in Chile.
Phosphine has a distinctive "absorption line" that these radio
telescopes discern at a wavelength of about 1mm. The gas is observed at
mid-latitudes on the planet at roughly 50-60km in altitude. The
concentration is small - making up only 10-20 parts in every billion
atmospheric molecules - but in this context, that's a lot.
Why is this so interesting?
Venus is not at the top of the list when thinking of life elsewhere in
our Solar System. Compared to Earth, it's a hellhole. With 96% of the
atmosphere made up of carbon dioxide, it has experienced a runaway
greenhouse effect. Surface temperatures are like those in a pizza oven -
over 400C.
Space probes that have landed on the planet have survived just minutes
before breaking down. And yet, go 50km up and it's actually
"shirtsleeves conditions". So, if there really is life on Venus, this is
exactly where we might expect to find it.
Why should we be sceptical?
The clouds. They're thick and they're mainly composed (75-95%) of
sulphuric acid, which is catastrophic for the cellular structures that
make up living organisms on Earth.
Dr William Bains, who's affiliated to the Massachusetts Institute of
Technology (MIT) in the US, is a biochemist on the team. He's studied
various combinations of different compounds expected to be on Venus;
he's examined whether volcanoes, lightning and even meteorites could
play a role in making PH3 - and all of the chemical reactions he's
investigated, he says, are 10,000 times too weak to produce the amount
of phosphine that's been observed.
To survive the sulphuric acid, Dr Bains believes, airborne Venusian
microbes would either have to use some unknown, radically different
biochemistry, or evolve a kind of armour.
"In principle, a more water-loving life could hide itself away inside a
protective shell of some sorts inside the sulphuric acid droplets," he
told Sky At Night. "We're talking bacteria surrounding themselves by
something tougher than Teflon and completely sealing themselves in. But
then how do they eat? How do they exchange gases? It's a real paradox."
What's been the reaction?
Cautious and intrigued. The team emphatically is not claiming to have
found life on Venus, only that the idea needs to be further explored as
scientists also hunt down any overlooked geological or abiotic chemical
pathways to phosphine.
Oxford University's Dr Colin Wilson worked on the European Space
Agency's Venus Express probe (2006-2014), and is a leading figure in the
development of a new mission concept called EnVision. He said Prof
Greaves' observations would spur a new wave of research at the planet.
"It's really exciting and will lead to new discoveries - even if the
original phosphine detection were to turn out to be a spectroscopic
misinterpretation, which I don't think it will. I think that life in
Venus' clouds today is so unlikely that we'll find other chemical
pathways of creating phosphine in the atmosphere - but we'll discover
lots of interesting things about Venus in this search," he told BBC News.
Prof Lewis Dartnell from the University of Westminster is similarly
cautious. He's an astrobiologist - someone who studies the possibilities
of life beyond Earth. He thinks Mars or the moons of Jupiter and Saturn
are a better bet to find life.
"If life can survive in the upper cloud-decks of Venus - that's very
illuminating, because it means maybe life is very common in our galaxy
as a whole. Maybe life doesn't need very Earth-like planets and could
survive on other, hellishly-hot, Venus-like planets across the Milky Way."
How can the question be resolved?
By sending a probe to investigate specifically the atmosphere of Venus.
The US space agency (Nasa) asked scientists recently to sketch the
design for a potential flagship mission in the 2030s. Flagships are the
most capable - and most expensive - ventures undertaken by Nasa. This
particular concept proposed an aerobot, or instrumented balloon, to
travel through the clouds of Venus.
"The Russians did this with their Vega balloon (in 1985)," said
team-member Prof Sara Seager from MIT. "It was coated with Teflon to
protect it from sulphuric acid and floated around for a couple of days,
making measurements.
"We could definitely go make some in-situ measurements. We could
concentrate the droplets and measure their properties. We could even
bring a microscope along and try to look for life itself."
https://www.bbc.com/news/science-environment-54133538
----- The end of the citation -----
Bye, All!
Alexander Koryagin
0 new messages