On its arduous voyage to Jupiter, NASA's Lucy spacecraft encountered the
first of ten asteroids on Wednesday.
The tiny Dinkinesh was located in the main asteroid belt beyond Mars,
around 300 million miles (480 million kilometers) distant, when the
spacecraft zipped by it on Wednesday. NASA described the spacecraft's
passing at 10,000 mph (16,000 kph) as "a quick hello."
Lucy tested its instruments on a dry run for the larger and more attractive
asteroids ahead, approaching Dinkinesh to within 270 miles (435 kilometers)
of the spacecraft. With a diameter of barely half a mile (1 kilometer),
Dinkinesh may be the tiniest space rock that Lucy has seen.
The Trojans, a group of undiscovered asteroids orbiting Jupiter that are
thought to be time capsules from the solar system's early days, are Lucy's
primary objectives. The spacecraft will pass eight Trojans that are thought
to be between ten and one hundred times larger than Dinkinesh. In 2033, it
is expected to speed past the last two asteroids.
Two years ago, NASA launched Lucy on her roughly $1 billion mission. The
skeleton remains of a human progenitor discovered in Ethiopia in the 1970s,
dating back 3.2 million years, inspired the name of the spacecraft. The
asteroid that Lucy will next pass by is named for Donald Johanson, one of
the people who discovered the fossil Lucy.
The spaceship has two solar wings, one of which is loose. It is thought to
be sufficiently stable for the duration of the trip, but flight controllers
gave up trying to bring it down.
The flyby on Wednesday completes the asteroid known by NASA as Autumn. In
September, NASA returned the first asteroid debris samples. It then sent a
spacecraft to Psyche, a rare asteroid rich in metal, in October.
Lucy's objective is not to stop at asteroids or gather samples like earlier
missions did.
The spacecraft's return of all its images and data from the flyby will take
at least a week.
As of right now, Dinkinesh is only "an unresolved smudge in the best
telescopes," according to a statement from lead scientist Hal Levison of
Southwest Research Institute.
