Should we be looking for life elsewhere in the universe? - Aomawa Shields
Astronomers have discovered thousands of
planets orbiting stars other than the Sun.
They come in all sizes,
at different orbital distances
from their stars.
The closest of them are trillions
of miles away,
and even the largest
are just fuzzy patches
in the fields of high-powered telescopes.
But if one of these planets is close
in size to the Earth
and orbits not too close
and too far away from its parent star,
it could be rocky and warm enough
to have oceans
and perhaps life.
Astronomers discover these potentially
habitable planets,
and their eyes get big and wide.
Could one of these distant worlds
carry the building blocks of life?
Or even a living, breathing, civilization?
Is the question, "Are we alone
in the universe?" about to be answered?
But wait.
Maybe we should
ask a different question first.
Should we try to find out
if we're alone in the universe?
If we do find the atmospheric
fingerprints of life
on one of these small,
distant worlds,
should we try to contact any beings
who may live there?
Is that wise?
Three decades ago, NASA decided
the answer was yes.
Voyager 1 and 2 were launched in 1977
to explore the giant planets
in the solar system.
Each spacecraft carried a golden
phonograph record,
a time capsule of sorts that included
clues and messages
meant to convey the story
of human civilization.
The contents of these gold-plated
copper disks were chosen by a committee
chaired by American astronomer
and author Carl Sagan.
They included over 100 images,
and a range of sounds
from the natural world:
ocean waves,
thunder,
the sounds of birds
and whales.
The records also included music from
many different time periods and cultures,
greetings in 55 languages,
and messages from
the President of the United States,
and the UN Secretary General.
They also included a map.
Each golden record displays the location
of our solar system
with respect to fourteen pulsars.
Their precise, unique frequencies
were indicated
so that intelligent,
extraterrestrial lifeforms
could use them to find the Earth.
Many years later, renowned physicist
Stephen Hawking said
that it was a mistake to give
an alien species a roadmap to our planet.
Hawking suspected that any
extraterrestrial life
probably wasn't any more complex
than microbes,
but he warned that if an advanced
alien species did visit Earth,
it could be as catastrophic as
Christopher Columbus's arrival was
for the Native Americans.
Meanwhile, the golden records
continue their journeys.
In 1990, both Voyager spacecraft
passed beyond the orbit of Pluto.
Voyager 1 entered interstellar space
in 2012,
and will reach the nearest stellar system
in 40,000 years.
If either spacecraft is discovered
by extraterrestrial life,
there's a possibility that they could
decipher the clues from the golden record
and one day reach our planet.
That's particularly true
if theirs is a much more
technologically advanced civilization.
That life could be benevolent,
as we would hope to be if humans are one
day able to achieve interstellar travel.
Or it could be hostile.
Searching for planets that might have life
means staring into a great abyss.
We'll likely have no clear knowledge
of the evolutionary stage,
sentience,
character,
or intentions of the first form of life
we discover.
So it's a risk to turn our eyes outwards.
We risk our very way of life.
But it may be a greater risk not to look,
to deny the very pioneering spirits
that help shape our own species.
We are all born curious about the world
and the universe.
Pursuing that curiosity is one of
humankind's greatest achievements.
Perhaps there is room to push
the frontiers of science,
provided that we cradle alongside
our fervor
another of humankind's greatest assets:
hope.
