A NASA spacecraft named Lucy rocketed into the sky with diamonds Saturday
morning on a 12-year quest to explore eight asteroids.
Seven of the mysterious space rocks are among swarms of asteroids sharing
Jupiter's orbit, thought to be the pristine leftovers of planetary
formation.
An Atlas V rocket blasted off before dawn, sending Lucy on a roundabout
orbital journey spanning nearly 4 billion miles (6.3 billion kilometers).
"I'm just elated," NASA's associate administrator, Robert Cabana, said
following liftoff. "This is the coolest darn mission."
Lucy is named after the 3.2 million-year-old skeletal remains of a human
ancestor found in Ethiopia nearly a half-century ago. That discovery got its
name from the 1967 Beatles song "Lucy in the Sky with Diamonds," prompting
NASA to send the spacecraft soaring with band members' lyrics and other
luminaries' words of wisdom imprinted on a plaque. The spacecraft also
carried a disc made of lab-grown diamonds for one of its science
instruments.
In a prerecorded video for NASA, Beatles drummer Ringo Starr paid tribute to
his late colleague John Lennon, credited for writing the song that inspired
all this.
"Lucy is going back in the sky with diamonds. Johnny will love that," Starr
said. "Anyway, If you meet anyone up there, Lucy, give them peace and love
from me."
The paleoanthropologist behind the fossil Lucy discovery, Donald Johanson,
said he was filled with wonder about this "intersection of our past, our
present and our future."
"That a human ancestor who lived so long ago stimulated a mission which
promises to add valuable information about the formation of our solar system
is incredibly exciting," said Johanson, of Arizona State University, who
traveled to Cape Canaveral for the launch.
Lucy's $981 million mission is the first to aim for Jupiter's so-called
Trojan entourage: thousands—if not millions—of asteroids that share the gas
giant's expansive orbit around the sun. Some of the Trojan asteroids precede
Jupiter in its orbit, while others trail it.
Despite their orbits, the Trojans are far from the planet and mostly
scattered far from each other. So there's essentially zero chance of Lucy
getting clobbered by one as it swoops past its targets, said Southwest
Research Institute's Hal Levison, the mission's principal scientist.
Lucy will swoop past Earth next October and again in 2024 to get enough
gravitational oomph to make it all the way out to Jupiter's orbit. On the
way there, the spacecraft will zip past asteroid Donaldjohanson between Mars
and Jupiter. The aptly named rock will serve as a 2025 warm-up act for the
science instruments.
Drawing power from two huge circular solar wings, Lucy will chase down five
asteroids in the leading pack of Trojans in the late 2020s. The spacecraft
will then swoop back toward Earth for another gravity assist in 2030 that
will swing it back out to the trailing Trojan cluster, where it will zip
past the final two targets in 2033.
It's a complicated, circuitous path that had NASA's science mission chief,
Thomas Zurbuchen, shaking his head at first. "You've got to be kidding. This
is possible?" he recalled asking.
Lucy will pass within 600 miles (965 kilometers) of each target; the biggest
one is about 70 miles (113 kilometers) across.
"Are there mountains? Valleys? Pits? Mesas? Who knows? I'm sure we're going
to be surprised," said Johns Hopkins University's Hal Weaver, who's in
charge of Lucy's black-and-white camera. "But we can hardly wait to see what
... images will reveal about these fossils from the formation of the solar
system."
NASA plans to launch another mission next month to test whether humans might
be able to alter an asteroid's orbit—practice in case Earth ever has a
killer rock headed this way.
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