The
first telescope to photograph a "pale blue dot" of
another Earth in a distant solar system may not be funded by NASA, the European
Space Agency, or some other government agency.
It
might come from Kickstarter.
Dubbed Project
Blue, the effort isn't run by hucksters out to peddle unrealistic technologies.
A consortium of professional scientists and engineers, some of whom work at
NASA, is running the show as a nonprofit called Mission
Centaur.
"We're
looking for a place that could support life," Supriya Chakrabart, an
optical and space scientist at University of Massachusetts Lowell whose part of
Project Blue, told Business Insider.
They
hope their 6-week-long panhandle on Kickstarter,
which starts November 15, nets them at least $1 million -- enough cash to pick up
the work a group of the researchers started at NASA but couldn't get more
funding to support.
They
say the money will go toward further design and research of the project.
The
group ultimately expects the mission to cost between $25 and $50 million to get
into orbit around Earth within the next 4 to 6 years. That price tag includes
sharing a ride on a rocket like SpaceX's Falcon 9, and it's nothing compared to
the billions NASA has spent on space observatories.
Once
in orbit, an epic 2-year stare-down would begin.
Chakrabart
said he's confident that crowdfunding the first stage of Project Blue will work
out, buying time to attract a big following -- and bigger funders later.
"After
ghosts and dinosaurs, space comes a close third, in terms of people's interest,"
he said.
Shooting
in the dark
Project
Blue's target is Alpha Centauri, a system that contains two of the closest
stars to our own solar system at just 4.4 light-years away.
One
of the stars, called Alpha Centauri A, is even sun-like.
However,
nobody knows if a blue marble like Earth -- a world with liquid-water oceans, a
cosy atmosphere, and other conditions necessary for life -- might lurk in the
double-star system. Not even Hubble, the planet-hunting Kepler space telescope,
or other advanced observatories could tell an astronomer.
So,
it's a bit of a gamble to make even a small telescope that's purpose-built to
stare down one star system.
But
Chakrabart and the other Mission Centaur scientists think it's a good bet. They
cite the most recent planet-hunting data from
Kepler, which pegs the odds of a rocky planet orbiting a star's "habitable
zone," or close enough to create liquid water, near 85%.
"Roughly
one out of every two stars has a potentially habitable planet," said
Ruslan Belikov, an astrophysicist at NASA Ames Research Center, in "The
Search for Earth Proxima" -- a short documentary about the
project. "The number of potentially habitable planets in our galaxy alone
is greater than the number of people alive on Earth."
According
to Lee Billings at Scientific American,
Belikov and another scientist in 2014 pitched NASA a telescope similar to
Project Blue, "but the agency passed over the speculative, narrowly
focused project."
That's
not too much of a surprise, since NASA likes its space telescopes more like
Swiss Army knives and able to view multiple targets with ease. The equipment
and techniques also weren't quite there at the time -- hurdles that Mission
Centaur no longer foresees.
"The
technology required to do this is only very recent. It hasn't been ready until
now," Brett Marty, the filmmaker behind the aforementioned documentary and
the executive director of Mission Centaur.
How
to photograph an 'Earth Proxima'
View
this content at Business Insider
At
roughly the size of a modest washing machine, Project Blue would be dinky space
telescope if built -- certainly compared to the school bus-size Hubble space
telescope.
But
it doesn't need to be large. It's only focused on one part of the sky and needs
minimal electronics (whereas Hubble needs large gyroscopes and multiple cameras
to move and take aim at different objects in space).
Project
Blue's ultimate task is resolving any very dim objects next to ones 1 billion
to 10 billion times brighter.
"Imagine
there's a marble next to a lighthouse in Cape Cod," Chakrabart said.
"OK, now try to image that marble from San Francisco. That is what we're
dealing with."
He
said that "three key technologies matured enough that we can tell people
with a straight face that we're now actually ready to go and do this
thing."
One
is a miniaturized version of a coronagraph, a complex instrument that can
blocks each star's blinding light and can reveal planets hiding in the glare.
"It's
kind of like playing tennis and the sun is in your eyes," Marty said.
"When you put your hand up to block it, you can see the ball coming. Here
we're suppressing both stars at once" and catching the balls. Keeping the
precision while shrinking what's normally a very large instrument wasn't easy,
they said.
The
next challenge was that "it's near impossible to make a perfect
mirror," or at least a large one, Chakrabart said.
The
solution? A "deformable" mirror, which is a computer chip-like array
of about 1,000 ultra-tiny (and very perfect) mirrors that can be programmed to
move with microscopic precision thousands of times a second, helping cancel out
any optical imperfections in the telescope.
The
third and final technical hurdle to making Project Blue possible was image
stabilisation.
"A
crisp image is what is needed because the planet would be so close to the
star," Chakrabart said. "We have built such a system and proven it
works to the level Hubble can point."
Marty
said it's like the gyros in consumer cameras that stabilise an image -- though
far more exacting. "This is really the reason we're able to do this mission
at such a low cost," he said.
To
prove the stabilizers worked well enough to keep Project Blue gazing endlessly
at Alpha Centauri, Chakrabart's team launched experimental prototypes toward
the edge of space, some 60 miles up. For the few minutes, they floated in the
thin air before falling back to Earth, they perfectly stabilised the
experimental rig.
If
all goes per plan, Project Blue will take hundreds or even thousands of
pictures of the star system in three colours (including blue), merge the giant
pile of images, and lift out a pale blue dot out from the noise of pixels.
"We
have to take care of every single possible event that could contribute to this
noise," Chakrabart said. "Therefore we've decided we need at least 2
years of measurement to convince ourselves we're seeing a true, Earth-like
planet."
What
if it works?
It's
important to note this isn't the closest star system we heard a lot about
earlier this year, a red dwarf star called
Proxima Centauri.
Although
a dogged team of astronomers strongly believe there's a rocky, Earth-size planet called Proxima b circling
that star in its habitable zone, Chakrabart and Marty said it's not a great
target for their ragtag operation.
At
about 4 million miles away from its star, Marty said, "there's a lot of
radiation. It's also a tricky target and hard to resolve, and it might not be
anything like our planet."
An
observatory like the behemoth James Webb Space Telescope might
be the first to study that world, though it wouldn't be a "pale blue
dot" photo -- more like a fuzzy heat signature that
could indicate "this is an incinerated hell hole" or "a useful
atmosphere and potentially water lurk here."
Project
Blue, of course, intends to return images of a habitable planets, like this:
If
it works, Russian billionaire Yuri Milner and his Breakthrough Starshot project
-- an effort to laser-propel tiny
spacecraft to
the Alpha Centauri or Proxima Centauri systems -- will have an intriguing new
target.
But
even if that pie-in-the-sky idea falls and all we're left with is an image of a
pale blue dot, it would be Earth-shattering.
"Finding
an Earth Proxima would be a transformative event in the history of
mankind," said Bill Diamond, president and CEO of th SETI Institute, in
Marty's documentary. "I would love to think that is something that helps
bring us together. It's a very unifying thing."
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