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https://www.nbcnews.com/science/space/lucy-spacecraft-will-visit-record-8-asteroids-rcna3075

Lucy in the sky: Spacecraft will visit record 8 asteroids

Advances in tech and design are behind this flurry of asteroid missions,
as well as the growing interest in asteroids and the danger they pose to
Earth.
Image: Lucy spacecraft

A United Launch Alliance Atlas V rocket with the Lucy spacecraft aboard
is rolled out of the Vertical Integration Facility to the launch pad, in
Cape Canaveral, Fla., on Oct. 14, 2021Bill Ingalls / AP
Oct. 15, 2021, 5:26 AM PDT / Updated Oct. 15, 2021, 7:17 AM PDT
By The Associated Press

CAPE CANAVERAL, Fla. — Attention asteroid aficionados: NASA is set to
launch a series of spacecraft to visit and even bash some of the solar
system’s most enticing space rocks.

The robotic trailblazer named Lucy is up first, blasting off this
weekend on a 12-year cruise to swarms of asteroids out near Jupiter —
unexplored time capsules from the dawn of the solar system. And yes,
there will be diamonds in the sky with Lucy, on one of its science
instruments, as well as lyrics from other Beatles’ songs.

NASA is targeting the predawn hours of Saturday for liftoff.

Barely a month later, an impactor spacecraft named Dart will give chase
to a double-asteroid closer to home. The mission will end with Dart
ramming the main asteroid’s moonlet to change its orbit, a test that
could one day save Earth from an incoming rock.

Image: Lucy spacecraft
A United Launch Alliance Atlas V rocket with the Lucy spacecraft aboard
on Oct. 14, 2021, at Cape Canaveral Space Force Station in Florida. Bill
Ingalls / AFP - Getty Images
Next summer, a spacecraft will launch to a rare metal world — an nickel
and iron asteroid that might be the exposed core of a once-upon-a-time
planet. A pair of smaller companion craft — the size of suitcases — will
peel away to another set of double asteroids.

And in 2023, a space capsule will parachute into the Utah desert with
NASA’s first samples of an asteroid, collected last year by the
excavating robot Osiris-Rex. The samples are from Bennu, a rubble and
boulder-strewn rock that could endanger Earth a couple centuries from now.

“Each one of those asteroids we’re visiting tells our story ... the
story of us, the story of the solar system,” said NASA’s chief of
science missions, Thomas Zurbuchen.

There’s nothing better for understanding how our solar system formed 4.6
billion years ago, said Lucy’s principal scientist, Hal Levison of
Southwest Research Institute in Boulder, Colorado. “They’re the fossils
of planet formation.”

Image: Lucy spacecraft rendering
Rendeering of the Lucy spacecraft approaching an asteroid.Southwest
Research Institute / via AP
China and Russia are teaming up for an asteroid mission later this
decade. The United Arab Emirates is also planning an asteroid stop in
the coming years.

Advances in tech and design are behind this flurry of asteroid missions,
as well as the growing interest in asteroids and the danger they pose to
Earth. All it takes is looking at the moon and the impact craters
created by asteroids and meteorites to realize the threat, Zurbuchen said.

The asteroid-smacking Dart spacecraft — set to launch Nov. 24 — promises
to be a dramatic exercise in planetary defense. If all goes well, the
high-speed smashup will occur next fall just 7 million miles away,
within full view of ground telescopes.

The much longer $981 million Lucy mission — the first to Jupiter’s
so-called Trojan entourage — is targeting an unprecedented eight asteroids.

Lucy aims to sweep past seven of the countless Trojan asteroids that
precede and trail Jupiter in the giant gas planet’s path around the sun.
Thousands of these dark reddish or gray rocks have been detected, with
many thousands more likely lurking in the two clusters. Trapped in place
by the gravitational forces of Jupiter and the sun, the Trojans are
believed to be the cosmic leftovers from when the outer planets were
forming.

“That’s what makes the Trojans special. If these ideas of ours are
right, they formed throughout the outer solar system and are now at one
location where we can go and study them,” Levison said.

Before encountering the Trojans, Lucy will zip past a smaller, more
ordinary object in the main asteroid belt between Mars and Jupiter.
Scientists consider this 2025 flyby a dress rehearsal.

Three flybys of Earth will be needed as gravity slingshots in order for
Lucy to reach both of Jupiter’s Trojan swarms by the time the mission is
set to end in 2033.

The spacecraft will be so far from the sun — as much as 530 million
miles — that massive solar panels are needed to provide enough power.
Each of Lucy’s twin circular wings stretches 24 feet across, dwarfing
the spacecraft tucked in the middle like the body of a moth.

Lucy intends to pass within 600 miles of each targeted asteroid.

“Every one of those flybys needs to be near-perfection,” Zurbuchen said.

The seven Trojans range in size from a 40-mile asteroid and its
half-mile moonlet to a hefty specimen exceeding 62 miles. That’s the
beauty of studying these rocks named after heroes of Greek mythology’s
Trojan War and, more recently, modern Olympic athletes. Any differences
among them will have occurred during their formation, Levison said,
offering clues about their origins.

Unlike so many NASA missions, including the upcoming Dart, short for
Double Asteroid Redirection Test, Lucy is not an acronym. The spacecraft
is named after the fossilized remains of an early human ancestor
discovered in Ethiopia in 1974; the 3.2 million-year-old female got her
name from the 1967 Beatles song “Lucy in the Sky with Diamonds.”

“The Lucy fossil really transformed our understanding of human
evolution, and that’s what we want to do is transform our understanding
of solar system evolution by looking at all these different objects,”
said Southwest Research Institute’s Cathy Olkin, the deputy principal
scientist who proposed the spacecraft’s name.

One of its science instruments actually has a disc of lab-grown diamond
totaling 6.7 carats.

And there’s another connection to the Fab Four, a plaque attached to the
spacecraft includes lines from songs they wrote, along with quotes from
other luminaries. From a John Lennon single: We all shine on . . . like
the moon and the stars and the sun.

Awesome!