Aliens
Opinion: We Could Find Life on
Another Planet. Do We Have the Will?
The discovery of geysers on Jupiter’s moon Europa has made it easier and
cheaper to determine whether life exists there, says Bill Nye. Now the mission
needs funding.
Every one of us has wondered if we're alone in the universe. Are there
living things elsewhere? Is the Earth the only place we'll ever know that
has life? That's the question posed by this month's cover story in
National Geographic. It's one I think we can answer, and maybe sooner
than you think.
Many of us think of alien life the way it's depicted in science fiction—
creatures that look quite a bit like humans in makeup and that all speak
English with a non-American accent. These made-up aliens hail from
distant star systems. But there's a place right here in our own solar
system that may be teeming with life. It's Europa, a moon of Jupiter,
one of the four that you can see with an inexpensive telescope, just as
Galileo Galilei did
If you have a telescope and an evening, you can chart the position of the
Galilean moons on a note card, as I used to do with my dad. They'll
appear as bright dots next to the larger disk of Jupiter. Observe them
just a couple of hours later, and you'll see how fast they're moving in
their orbits. Europa is unique among these four—it has an enormous
ocean. In fact Europa's ocean has twice the volume of seawater that we
have here on Earth.
In astrobiology, the study of extraterrestrial life, it's generally agreed
that living things need a solvent to move their chemicals around. So far,
no one can come up with any solvent that's better for life than liquid
water. Europa is inundated, even more than Earth is.
Out there, hundreds of millions of kilometers from the sun, you might
expect the water to be entirely frozen. But Europa orbits Jupiter, and
the giant planet's enormous gravity stretches and compresses Europa
like a rubber ball squeezed in your palm. That motion becomes heat. It's
like rubbing your hands together to keep warm, only on a planetary
scale.
So while the outer core of Europa's ocean is a shell of ice some 20
kilometers (12.4 miles) thick, what's below is liquid. Shielded from
radiation by solid ice and with plenty of internal heat, the sea of this
alien world could well harbor life. Many investigators think it's certainly
worth investigating, because a discovery of living things on another
world would utterly change this one.
Sniffing Europa's Geysers
For the first time in history we have the chance to send a spacecraft out
there to see if something is swimming around in all that water. Even
better: Because of a remarkable feature of Europa, this mission would
not be wildly expensive. We discovered it last year with the Hubble
Space Telescope: Europa has geysers that continuously shoot Europa's
extraterrestrial seawater into outer space. They shoot hundreds of tons
of the moon's ocean to an altitude four times the height of our own
Mount Everest. Can you imagine what such a thing would be like here
on Earth? It would be astounding. It would be the number one wonder
of our world.
Europa's geysers present us Earthlings with a remarkable, tantalizing
opportunity. We could design and build a robotic spacecraft that would
fly through these plumes and sniff around. It would cost each U.S.
taxpayer about the equivalent of one reasonably priced burrito, albeit
without extra guacamole. All we have to do is decide to go. The
proposed name for the mission is the Europa Clipper. Some work has
been done on the design, but funding for the project has been unsteady.
At the Planetary Society we work to put the funding for missions like
this into law so that NASA can get going.
Imagine it. The Clipper would make dozens of orbits, mapping the
Europan surface with cameras and radar, flying through Europa's
seawater plumes and analyzing them, looking for the chemistry of life,
and perhaps finding some otherworldly microbes. That would be
astonishing.
The Bottom Line
At NASA's Jet Propulsion Lab, engineers, scientists, and skilled
technicians design interplanetary spacecraft and schemes to get them to
their extraordinary destinations. Europa mission plans have always
come in pretty expensive, because everybody figured that we'd have to
land there and drill through many kilometers of solid ice, potentially
contaminating any ecosystem that might already be there. That's a
strange but real science-fiction-style concern. But if we can analyze
samples flung out into space, there's virtually no chance of
contamination, and there's no need to build landing gear, drills, or
complex anchor and tether systems. It would be much cheaper than
anyone had calculated.
People everywhere know and respect NASA. It's the best brand the
United States has. But like everything else, the agency's budget has been
reduced over the years; it hasn't kept up with inflation.
Within NASA's budget is a line for planetary science. It's the part of
NASA that does the most amazing things. Other space agencies put
spacecraft in orbit around the Earth; a few even go to Mars. But no
other space agency on Earth can land anything on Mars, let alone lower
a small car there from a rocket-powered crane. (Read "Mars Gets Its
Close-Up" in National Geographic magazine.) And no other agency can
mount a mission like the Europa Clipper. The expertise is here in the
United States. It allows people here to solve interplanetary problems
that have never been solved before. It leads to innovation that, at last
reckoning, produces $3.60 for every dollar that goes in.
The decision rests with the White House, which can ask permission
from Congress to build the spacecraft, and with Congress, which can
agree to set aside the money. That's where we at the Planetary Society
come in. It's the reason my old professor Carl Sagan was one of the
society's founders. We advance space science and exploration. With the
support of our 45,000 members, people like you, we work with
Congress and the administration, reminding them of the enormous
value of planetary exploration and the great bargain that it is.
Just think what it would mean if we were to find a living thing in a
geyser of seawater on another world. Every one of us here on Earth
would stop and ponder what it means to be a living thing. I hope it
would fill each of us with reverence for the cosmos and for our place
within it. A mission to Europa would bring humankind together—and
perhaps change the world.
Bill Nye is the CEO of the Planetary Society. Follow him on Twitter.