The deep impact of Nasa’s blast
Like a script of a Hollywood film, a planetary defence experiment against asteroids was a smashing success
TToby Shapshak he biggest thing that happened in the world last month was out of this world. Literally. Forget non-practising energy minister Gwede Mantashe being booed or Eskom’s worst-ever #loadsh*tting.
Nasa made history by smashing a rocket into an asteroid called Dimorphos. That is potentially life-changing, or potentially planet-saving. Nasa’s Double Asteroid Redirection Test (Dart) project has had space geeks like me excited for months. A vending machine-sized satellite was sent to slam into the asteroid. Two weeks out, it deployed a micro-satellite called LICIACube to capture the impact. Let’s call it a selfie satellite. The footage is compelling and mind-blowing. It’s the stuff we see in apocalyptic movies. From LICIACube in the distance, you see the small dot hit the big dot and a plume explode out.
Seen from the perspective of the Dart satellite the asteroid gets closer and closer, with amazingly high-resolution images of what looks like the surface of the moon. The satellite held a single instrument, the Didymos Reconnaissance and Asteroid Camera for Optical navigation, which sent back high-resolution images of the odd-shaped space rock. In the final 11 seconds, it sent back an image a second – each more beautiful than the last.
The test was designed for the kinds of doomsday scenarios so beloved of Hollywood movies, in which an asteroid on a course to hit Earth needs to be diverted.
“We’re embarking on a new era of humankind. An era in which we potentially have the capability to protect ourselves from a dangerous, hazardous asteroid impact,” said Lori Glaze, director of Nasa’s Planetary Science Division. Costing $325-million and weighing just over half a ton (544kg), Dart had the budget of a Hollywood action flick and was clearly money well spent, given the space industry’s enthusiastic response. The size of Rome’s Colosseum, the 160m-wide Dimorphos asteroid was chosen to demonstrate what’s known as the “kinetic impact” planetary defence strategy.
“It is amazing, but it is awfully eggshaped,” said Carolyn Ernst, an instrument scientist for Johns Hopkins Applied Physics Laboratory (APL), of Dimorphos, which is in a binary orbit around our sun with another larger asteroid named Didymos.
“We move the little guy, but the big guy is like an anchor. It’s holding it back,” said Andy Cheng, chief scientist for planetary defence at the APL, which ran the project for Nasa. “The orbit of the whole system around the sun changes by such a tiny amount that it’s hard to measure.”
The ultimate aim was to test how to redirect a wayward asteroid from hitting the planet. It’s analogous to getting Planet Gwede to change course away from his self-destructive trajectory towards South Africa’s own ruinous problems. If only we could hit him with a satellite to change his direction…. We can but dream. Nasa would have to send more than one vending machine-sized rocket to move him away from his kamikaze path of economic suicide.
“I definitely think that, as far as we can tell, our first planetary defence test was a success, and I think we can clap to that. Yeah, I think Earthlings should sleep better. I know I will,” said Elena Adams, Dart mission systems engineer at the APL.
If only we could smash something into Planet Gwede….
The ultimate aim was to test how to redirect a wayward asteroid from hitting the planet. It’s analogous to getting Planet Gwede to change course away from his selfdestructive trajectory
Tony SHApsHAk Is EDItor-In-CHIEF oF Stuff. Co.zA AnD puBlIsHEr oF SCrollA.AFrICA.