At a talk in Germany in 2012, astronomer
Seth Shostak bet everyone in the room a Starbucks coffee that
the human race would make first contact with alien life within
24 years.
Seven years later, Shostak, who works for the California-based
SETI Institute, stands by his bet.
And just one encounter with a thriving alien civilization or
even just living or dead microbes could change, well,
everything. “The universe, we could conclude, is teeming with
life,” Shostak told The Daily Beast.
Shostak’s position is increasingly uncontroversial. More and
more scientists believe that, yes, there’s life beyond Earth.
“Why should we be the only ones?” Martin Dominik, an astronomer
at the University of St. Andrews in Scotland, asked The Daily
Beast.
(And no, all those recent sightings of supposed UFOs by U.S.
Navy pilots don’t count. Whatever those weird flying objects
are, scientists almost unanimously dismiss the possibility
they’re alien visitors.)
First contact looks more and more likely. But if we’re going to
find extraterrestrial life within a decade or so, we might need
to switch up exactly where, and how, we’re looking. One
hellishly hot volcanic planet in particular practically begs for
our attention.
At present, Earth’s scientists are pursuing basically two
separate efforts for finding non-Earth life. One is essentially
passive, and involves listening for signals from alien
civilizations. The SETI Institute— that stands for “search for
extraterrestrial intelligence”—spearheads that effort with its
arrays of radio receivers.
The other is active. We send out probes to distant planets and
moons and scan even farther-away heavenly bodies with powerful
telescopes that can help us to determine the makeup of a
planet’s atmosphere.
The passive effort, which is focused on detecting intelligent
life in some faraway technological civilization, has one huge
flaw. Civilizations most likely are on planets. Planets orbit
stars. And stars emit a lot of radiation, much of which our
radio receivers read as static noise.
Any distant observer of our own solar system would probably
never detect human civilization despite all our electronic
activity, Terry Virts, a former NASA astronaut, explained on the
science podcast Oh No Ross and Carrie.
“If we transmitted with all of our power possible, you’d never
hear it because the sun would overwhelm it [with] the radio
signals that it makes,” Virts said.
“Any distant observer of our own solar system would probably
never detect human civilization despite all our electronic
activity.”
So maybe active efforts are more likely to turn up evidence of
alien life. The world’s space agencies and science organizations
have organized a wide array of probes and telescope surveys that
could find E.T. relatively soon.
There are rovers on Mars as well as a NASA plan to land
astronauts on the Red Planet sometime in the 2030s. Former NASA
scientist Gil Levin, for one, told The Daily Beast the agency
found evidence of microbes on Mars way back in 1976. NASA
insisted the data was faulty.
Looking past the Red Planet, the European Space Agency and NASA
are both planning to launch space telescopes that could scan the
atmospheres of “exo-planets” potentially hundreds of trillions
of miles from Earth.
NASA’s new James Webb telescope, billed by the agency as the
“world’s premier space science observatory,” should be ready by
2021. The ESA’s Remote-Sensing Infrared Exoplanet Large-Survey
telescope is slated for a 2028 launch.
The two sensors will make a powerful pair. Douglas Vakoch, who
heads the METI International research organization in San
Francisco (METI stands for “Messaging Extraterrestrial
Intelligence”), is an advocate of SETI’s passive approach to
finding life, but he told The Daily Beast even he believes that,
after 2028, the space telescopes will be the best way to hunt
for E.T.
In that case, “E.T.” almost certainly would mean microbes.
Michael Varnum, an Arizona State University psychologist who
studies possible first-contact scenarios, told The Daily Beast
that the aliens we’re most likely to find are single-cell
organisms, either living or fossilized.
He points to the so-called “Drake Equation” and other
calculations. They “suggest that such life should be far more
common than intelligent life,” Varnum said.
NASA agrees. In addition to landing robots and eventually people
on Mars, the space agency plans to send a probe to Europa, a
moon of Jupiter, in 2025. The $4-billion Europa Clipper is
equipped with instruments that can analyze the plumes of water
vapor that scientists suspect occasionally jet from Europa’s
surface, and which could in theory support microbial life.
If the probe works over Europa, it could form the basis of a
later probe that scientists want to send to Enceladus, a moon of
Saturn, some time in the late 2020s or 2030s. Enceladus, like
Europa, appears to have water. Lots of it. And it shoots it
straight into space in the form of enormous geysers, making it
fairly straightforward to investigate.
But there’s an even better place to look.
“At some point we should really check out Venus and its lower
atmosphere,” Dirk Schulze-Makuch, an astrobiologist at the
Technical University Berlin, told The Daily Beast.
Venus, the second planet from the sun, might seem like an
unlikely place to look for life. It’s hot. Really hot. “The
atmosphere traps the small amount of energy from the sun that
reaches the surface along with the heat the planet itself
releases,” NASA explained on its website. “This greenhouse
effect has made the surface and lower atmosphere of Venus one of
the hottest places in the solar system.”
“Having originated in a hot proto-ocean or been brought in by
meteorites from Earth (or Mars), early life on Venus could have
adapted to a dry, acidic atmospheric niche as the warming planet
lost its oceans.”
Then there’s the planet’s toxic carbon-dioxide atmosphere and
sulfuric-acid clouds. Still, for all its hot poison, Venus could
support microbes, Schulze-Makuch explained in a 2004 paper he
co-wrote with, among others, David Grinspoon from the
Arizona-based Planetary Science Institute.
“Having originated in a hot proto-ocean or been brought in by
meteorites from Earth (or Mars), early life on Venus could have
adapted to a dry, acidic atmospheric niche as the warming planet
lost its oceans," Schulze-Makuch and Grinspoon wrote.
A bunch of NASA researchers got so excited by the prospect of
life on Venus a few years back that they concocted a fairly
outlandish scheme to deploy giant, manned airships in the
planet’s toxic atmosphere.
In truth, there’s no need to send people to investigate Venus
and its potential “niche” lifeforms. “There are probes you could
send that are orders of magnitude less cost,” Grinspoon told The
Daily Beast back in 2018. “Send machines.”
We’re already listening for radio signals and getting ready to
scan distant planets, probe Europa and possibly Enceladus, and
send alien-hunters to Mars. As humanity enters perhaps the most
important phase of its decades-long search for extraterrestrial
life, maybe Venus should be on the list, too.
But there’s one big reason it isn’t. Space missions are
expensive. And you have to convince politicians to pay for them.
“To get the political impetus to [probe Venus] would be much
more difficult than for Mars,” Schulze-Makuch explained. “One
reason is because Mars is also a potential site for a human
mission and settlement, while Venus is clearly not.” |
