Asteroids Better Think Twice About Heading For Earth Now That We Have This Laser

Despite NASA's assurances that an asteroid won't hit Earth for at least another 100 years, we can never be too careful here on Starship Earth. Planning for a potential impact event is an understandable precaution.

But what's the best way to steer an asteroid away from an impact course with Earth? You could shoot it with atom bombs, or just smash stuff into it really really fast. You could hire a ragtag group of offshore oil rig roughnecks to—never mind. There are a lot of ways to skin an asteroid, and last week, researchers at UC Santa Barbara unveiled a new prototype based on a solution we've actually explored before: lasers.

Called DE-STAR, or Directed Energy System for Targeting of Asteroids and exploRation program (the 'R' is a stretch, UC Santa Barbara), UCSB's Experimental Cosmology Group demonstrated the viability of a laser option.

In the test, a laser focused on a basalt target, which shares similar properties with asteroids. In simulated, space-like conditions DE-STAR was able to slow, stop and even reverse the rotation of the target. In other experiments, the beam was focussed on a single spot on the target, sublimating the mineral to gas, creating a plume that could in theory propel an asteroid to a different, non-Earth trajectory.

According to DE-STAR's creators, UC Santa Barbara physicist Philip Lubin and Gary B. Hughes, a researcher and professor at California Polytechnic State University, San Luis Obispo, DE-STAR could also be used for exploration and mining, two human activities that are predicated on our ability to control the rotation of an object.

"All asteroids rotate; it's just a question of relative to whom and how fast. To mine an asteroid, it needs to be moving slowly enough so you can capture it," Lubin explained in a press release. "Our lab experiments show very graphically a practical way to de-spin or redirect an asteroid. It's a vivid demonstration that the technique works very well."

It's a promising development in allaying a civilizational anxiety of being smashed from above. One has to question Lubin's choice to name a giant laser in Earth orbit anything evocative of that other space based laser, though.