The United Launch Alliance Atlas V rocket blasts off on Thursday, Sept. 8, 2016, carrying the OSIRIS-Rex spacecraft from Cape Canaveral Air Force Station's Space Launch Complex-41. The spacecraft will travel to the near-Earth asteroid Bennu to survey the surface, then retrieve at least 60 grams (2.1 ounces) of surface material and return it to Earth for study. (Red Huber/Orlando Sentinel/TNS)
The United Launch Alliance Atlas V rocket blasts off on Thursday, Sept. 8, 2016, carrying the OSIRIS-Rex spacecraft from Cape Canaveral Air Force Station's Space Launch Complex-41. The spacecraft will travel to the near-Earth asteroid Bennu to survey the surface, then retrieve at least 60 grams (2.1 ounces) of surface material and return it to Earth for study. (Red Huber/Orlando Sentinel/TNS) Credit: Red Huber

Goddard Space Flight Center, Md. — NASA launched a spacecraft skyward Thursday evening on an ambitious seven-year voyage to intercept an asteroid more than 100 million miles from Earth, scoop up a piece of it and bring the sample home.

Only once before has a spacecraft successfully completed such a mission, and never have astronomers attempted to gather such a large asteroid sample. The material that OSIRIS-REx collects from its target, Bennu, is made of the same substances that were present at the beginning of the solar system. Scientists believe they could help reveal how the planets were made and perhaps even how the ingredients for life arrived on Earth.

The spacecraft blasted off at 7:05 p.m. Eastern from Cape Canaveral, Fla., streaking across a cloudless sunset sky. At Goddard Space Flight Center in Greenbelt, Md., a crowd of scientists and their families burst into applause, then fell into an anxious silence as they watched a livestream of the rocket accelerating upward. At one minute after the clockwork-perfect liftoff, the spacecraft had gone supersonic, surpassing the speed of sound.

The image on the screen shifted to show the back of the rocket, speeding away from the pale blue curve of Earth, and the tension in the room broke. By 8:05 p.m., the spacecraft escaped Earth’s gravity and shed the Atlas V rocket that had borne it upward.

“OSIRIS-REx is flying free,” came the announcement from mission control. More than a dozen years and a billion dollars after it was first conceived, NASA’s first-ever asteroid sample return mission was fully underway.

The destination is a small, dark asteroid roughly as wide as the Empire State Building is tall. Born out of the chaos surrounding the sun’s formation, a survivor of the cataclysmic accumulation, bombardment and rearrangement of planets, Bennu is a 4.5-billion-year-old relic.

“It really is a time capsule,” said Dante Lauretta, the mission’s principal investigator.

But before OSIRIS-REx can attempt to open that capsule, it has to get there. The asteroid is classified as a “near-Earth object” and has a small but non-zero chance of crashing into our planet in the next 200 years, but it still is a long, long distance away.