In a First, NASA Craft Heads to Metal Asteroid

NASA's Psyche spacecraft rocketed away Friday on a six-year journey to a rare metal-covered asteroid. Most asteroids tend to be rocky or icy, and this is the first exploration of a metal world. Scientists say it may be the battered remains of an early planet's core and could shed light on the inaccessible centers of Earth and other rocky planets. SpaceX launched the spacecraft into an overcast midmorning sky from NASA's Kennedy Space Center. Named for the asteroid it's chasing, Psyche should reach the huge, potato-shaped object in 2029, the AP reports. "It's so thrilling," said Laurie Leshin, director of NASA's Jet Propulsion Laboratory. Added Arizona State University's Jim Bell, part of the Psyche team: "What a great ride so far."

An hour later, the spacecraft separated successfully from the rocket's upper stage and floated away, drawing applause from ground controllers. After decades of visiting faraway worlds of rock, ice, and gas, NASA is eager to pursue one coated in metal. Of the nine or so metal-rich asteroids discovered so far, Psyche is the biggest, orbiting the sun in the outer portion of the main asteroid belt between Mars and Jupiter alongside millions of other space rocks. It was discovered in 1852 and named after Greek mythology's captivating goddess of the soul. "It's long been humans' dream to go to the metal core of our Earth. I mean, ask Jules Verne," lead scientist Lindy Elkins-Tanton of Arizona State University said before the launch.

"The pressure is too high. The temperature is too high. The technology is impossible," she said. "But there's one way in our solar system that we can look at a metal core, and that is by going to this asteroid." Astronomers know from radar and other observations that the asteroid is big—about 144 miles across at its widest and 173 miles long. They believe it's brimming with iron, nickel, and other metals, and quite possibly silicates, with a dull, predominantly gray surface likely covered with fine metal grains from cosmic impacts, per the AP. Otherwise, it's a speck of light in the night sky, full of mystery until the spacecraft reaches it after traveling more than 2 billion miles.

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