Climate modelling research indicates that
Venus could be a lovely place to visit –
with a time machine.
Earth and Venus are each about four and a
half billion years old.
Although Venus is a veritable hellscape today,
it’s good to keep in mind that Earth was
probably equally uninhabitable for about a
billion years.
It got better.
And according to a new study out of NASA’s
Goddard Institute for Space Studies, Venus
has changed, too: It may have been habitable
to life as we know it for up to two billion
years of its history.
Venus today is exactly the kind of place humans
don’t want to hang out.
There’s practically no water because the
surface temperature can reach 462 degrees
Celsius – that’s 864 degrees Fahrenheit,
which is the perfect temperature to cook a
crispy Neapolitan pizza and more than hot
enough to melt aluminum.
The atmospheric pressure on its surface is
90 times Earth's,
meaning the very air would crush you.
And by “air” I mean mostly carbon dioxide.
Researchers also think Venus’s thick clouds
discharge more lightning than we see on Earth.
And those clouds are made of sulfuric acid.
But as recently as 715 million years ago,
Venus may have had shallow oceans
and an atmosphere comparable to Earth’s today –
with mean
temperatures a few degrees cooler than ours, even.
The team from NASA adapted the climate-modelling
tools used here on Earth to create a 3D climate
simulation for ancient Venus.
They built the model based on data and hypotheses
from NASA’s Pioneer and Magellan space probes
and the ESA’s Venus Express orbiter.
They found that, even though its distance
from the sun means that ancient Venus would
have received about 40 percent more sunlight
than Earth does today, Venus’s global temperatures
were likely mitigated by its incredibly slow
rotation rate.
A day on Venus lasts about 117 Earth days.
Its day side receives sun exposure for about
two Earth months at a time.
In the simulation, that produced thick rain
clouds that shielded the surface and kept
the planet temperate.
These results are dependent on Venus’s topography
and rotation rate not changing much over the
past few billion years.
Which is likely, but still in question -- so
the team played around with the model to see
whether feasible topographical or rotational
adjustments could have changed their results.
Increasing the steepness of the mountains
and ocean basins to Earth-type levels raised
the temperatures in the model – though they
stayed within a life-friendly range.
Speeding the rotational rate only made the
model too hot for life when they made Venus’s
days 7 times shorter – a mere 16 Earth days
per single Venus day.
The research is thought provoking on its own:
Ancient Earth sponges and algae may have had
neighbors in our solar system!
But it’s really part of NASA’s push to
identify exoplanets capable of harboring life
as we know it.
We previously thought planets as close to
a star as Venus may have always been too hot
to support life, but now we can expand our
search.
But what do you think: Where could the search
for extraterrestrial life take us?
Get in touch and let us know.
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