If you’ve been on the internet at all this past week, you’ve seen some version of how NASA is brainstorming a plan — appropriately called HAMMER (Hypervelocity Asteroid Mitigation Mission for Emergency Response) — to deflect smaller asteroids and nuke behemoth flying rocks like Bennu.
We might not need to nuke Bennu, which is approximately the size of the Empire State Building, even if does defy the 1 in 2,700 odds of slamming into Earth in the year 2135, if for any reason beyond creating a sci-fi spectacle. Gizmodo found out this is part of the reason NASA’s OSIRIS-REx spacecraft is floating out toward Bennu to probe for a sample that it will return by 2023 for further analysis.
“Even just painting the surface a different color on one half would change the thermal properties and change its orbit,” NASA’s OSIRIS-REx Flight Dynamics System Manager, Michael Moreau, told Gizmodo.
Wait. You read that right. Graffiti-ing an asteroid might throw it off course enough to bring that 1 in 2,700 chance down to zero.
Asteroids, and everything else in our solar system, are constantly being bombarded with solar particles. An object the size of Earth is too massive for these particles to actually have any impact. Bennu is a lightweight in comparison.
Pressure from solar particles can affect its orbit, and scientists can take advantage of that by giving the radiation a better chance of pushing it out of our planet’s way. Painting one side a different color could make a difference in how much radiation the asteroid absorbs, and more radiation can exert more pressure to divert it.
Humanity still has to find out more about these space projectiles. Not enough is yet known about Bennu’s orbit and chemical composition to be absolutely sure that a paint job would make any difference. OSIRIS-Rex (Origins Spectral Interpretation Resource Identification Security - Regolith Explorer) is headed out there to find out everything it can about Bennu so NASA scientists can decide how to best avoid a major catastrophe in the next 120 years.
Bennu is unlikely to make our species extinct even if it does strike, though the destruction would be astronomical. What should concern us more is that the only asteroids which are really on our radar are the mammoth ones that look like an apocalypse waiting to happen. There are so many smaller asteroids which may not take out as much of the population as something like Bennu could, but may have a much higher chance of actually smashing into Earth’s surface. Destruction is destruction even if it doesn’t erase half the planet.
At least for now, the only universe where asteroids are regularly crashing into Earth is science fiction.