Astronomers are planning a fishing trip to land an extraterrestrial
interloper on Earth: A small meteorite from another star system that crashed
into the Pacific Ocean with energy equivalent to about 121 tons (110 metric
tons) of TNT.
The team, from Harvard University, hopes to find fragments of this
interstellar rock — known as CNEOS 2014-01-08 — which slammed into Earth on
January 8, 2014.
"Finding such a fragment would represent the first contact humanity has ever
had with material larger than dust from beyond the solar system," Amir
Siraj, an astrophysicist at Harvard University and the first author of a new
paper published on the non-peer reviewed pre-print service
ArXiv on
CNEOS 2014-01-08, told Live Science in an email.
Siraj identified the object's interstellar origin in a 2019
study with 99.999% confidence, but it wasn't until May 2022 that it was
confirmed to Siraj by the U.S. Space Command. There are no known witnesses
to the object striking Earth.
"It struck the atmosphere about a hundred miles [160 kilometers] off the
coast of Papua New Guinea in the middle of the night, with about 1% the
energy of the Hiroshima bomb," Siraj said.
Measuring just 1.5 feet (0.5 m) wide, CNEOS 2014-01-08 now appears to have
been the first interstellar object ever discovered in our solar
system.
Previously, an oblong object called 'Oumuamua held that title. Discovered in
2017 during the Pan-STARRS sky survey, the space rock zipped through our
solar system at nearly 57,000 mph (92,000 km/h), and later, Harvard
astrophysicist Avi Loeb, a colleague of Siraj, claimed it might be an alien
machine. 'Oumuamua's discovery was followed in 2019 by comet 2I/Borisov, the
first interstellar comet, which was spotted by amateur astronomer Gennadiy
Borisov in Crimea.
CNEOS 2014-01-08 is thought to be from another star system because it was
traveling at 37.2 miles per second (60 kilometers per second) relative to
the sun. That's too fast for it to be bound by the sun's gravity.
"At the Earth's distance from the sun, any object traveling faster than
about 42 kilometers per second [26 miles per second] is on an unbounded,
hyperbolic escape trajectory relative to the sun," Siraj said. "This means
that CNEOS 2014-01-08 was clearly exceeding the local speed limit for bound
objects [and] it didn't cross paths with any other planets along the way, so
it must have originated from outside of the solar system."
Cut to Siraj and Loeb's Galileo Project, a $1.6 million expedition to lower
a magnet similar in dimensions to a king size bed at 1.3 degrees south,
147.6 degrees east, the U.S. Department of Defense's location of the
meteorite's resting spot. That's about 186 miles (300 km) north of Manus
Island in the Bismarck Sea in the southwest Pacific Ocean.
|
| The meteorite fragments are thought to be 186 miles (300 km) north of Manus Island (marked in red) in the Bismarck Sea in the southwest Pacific Ocean. (Image credit: Map Data Copyright 2022 Google) |
CNEOS 2014-01-08 greatly exceeded the material strength of a typical iron
meteorite, which should make it even easier to recover, according to Siraj.
Material strength refers to how easily something can resist being deformed
or damaged by a load. "Most meteorites contain enough iron that they will
stick to the type of magnet we plan on using for the ocean expedition," he
said. "Given its extremely high material strength, it is very likely that
the fragments of CNEOS 2014-01-08 are ferromagnetic."
Leaving from Papua New Guinea, the Galileo Project's ship would use a
magnetic sled on a longline winch, which will be towed along the seabed at 1
mile (1.7 km) for 10 days. It's hoped the magnet can recover tiny fragments
of the meteorite, measuring as small as 0.004 inches (0.1 mm) across.
However, it's unclear when the astronomers will be able to mount their
expedition. The Galileo Project already has $500,000 committed, with a
further $1.1 million required to make it a reality. That's good value
compared to a space mission, according to Siraj.
"The alternative way to study an interstellar object at close range is by
launching a space mission to a future object passing through the Earth's
neighborhood," said Siraj, who with Loeb is also working out the details of
such a mission should another object like 'Oumuamua appear in the solar
system. "But that would be 1,000 times more expensive at about $1 billion."
Originally published on
Live Science.
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Space & Astrophysics