NASA just sent a spacecraft to a distant asteroid as part of its planetary defense program.
Dimorphos, an asteroid, is not a threat to Earth. However, the Double Asteroid Redirection Test is not for high stakes. NASA wants to see if it can change a space rock’s orbit — just in case it ever discovers a large one bound for Earth.
“We’re embarking on a new era of humankind, an era in which we potentially have the capability to protect ourselves from something like a dangerous, hazardous asteroid impact,” Lori Glaze, director of NASA’s planetary science division, said on a livestream shortly after the DART impact.
After 10 months of traveling to the distant, desolate rock, DART finally reached its destination — and met its demise — at 7:14 p.m. ET on Monday. A livestream from spacecraft’s camera captured Dimorphos in clear view during the last minutes.
Its surface had giant boulders, which were later resolved. Then, DART moved closer to its target and smaller boulders, and finally, the small rocks on the asteroid’s surface before the feed was cut off. NASA had planned for DART to crash into the craggy surface, and its camera feed died. These are the final moments.
The DART control area erupted with cheers, applause and congratulations.
Ralph Semmel, the director of Johns Hopkins’ Applied Physics Laboratory which developed the spacecraft, stated that “Never before has I been so excited by a signal going away, and an image stopping,” NASA’s live broadcast reflected.
“Normally, a spacecraft loses signal is a very serious thing but in this case it was an ideal outcome,” he said in a briefing.
NASA/Johns Hopkins APL
DART hit the asteroid about 17 meters from its center — a bullseye in astronomical scales.
Now comes more work. Astronomers are poised to point their telescopes to Dimorphos as it continues to orbit a much larger asteroid called Didymos. DART was designed to give Dimorphos just enough lift to make its orbit shift by about 1%. If all went according to plan, it should have moved closer towards the larger rock.
If NASA ever has to launch an asteroid-bumping missions to deflect a threat to Earth, the data from these follow-up observations will prove crucial.
