What should the world do about the potential threat of a catastrophic asteroid collision? This month NASA established the Planetary Defense Coordination Office to manage the issue. Meanwhile, the Russians and the Europeans are talking about diverting nasty space rocks with nuclear weapons.
All this comes as cosmic threats are getting ready to hit prime time, in the form of an NBC comedy titled “You, Me and the Apocalypse.” (The threat in this case is a comet, not an asteroid.)
Former astronaut Ed Lu, CEO of the B612 Foundation, is glad for all the attention. For years, B612 has been trying to raise awareness about the asteroid threat, with mixed success. In a statement posted on Facebook today, Lu noted that NASA’s actions come in response to a highly critical internal report about NASA’s asteroid-hunting effort. Another indication of a turning tide is contained in last month’s omnibus spending bill, which sets aside $50 million for the effort during fiscal year 2016. That’s 10 times more than NASA was spending in 2010.
The Planetary Defense Coordination Office will focus on detecting objects as small as 100 feet (30 meters) across. That category includes asteroids and comets that may not pose an “Armageddon”-style threat to global civilization, but could still wipe out a city. (In comparison, the asteroid that blew up over the Russian city of Chelyabinsk in 2013 is thought to have been about 60 feet wide.)
The charter for the Planetary Defense Coordination Office sets up a clear chain of command for assessing future threats.
“While there is much to celebrate about this development, what is really important is how well NASA actually succeeds in carrying out the mandate of the PDCO,” Lu writes. “There is still work to be done, including the actual funding of an infrared space telescope for finding asteroids, and recognizing that planetary defense is not wholly a science problem (but rather also a technical and policy problem).”
B612 has proposed building and launching an infrared space telescope dubbed Sentinel with private funding, while NASA is considering a different concept known as NEOCam.
What if astronomers identify a threatening asteroid? That’s where a U.S.-European-Russian program called NEOShield enters the picture. NEOShield has been working on scenarios for diverting a near-Earth object, or NEO, that’s on a potential collision course. Last weekend, Russian news media reported that one of the scenarios involves nuclear weapons.
The Tass news agency quoted Russian scientists as saying that diverting an asteroid by setting off a nuclear blast in its deep-space vicinity would be the most effective way to head off a collision with Earth.
A document prepared by Russia’s Central Scientific Research Institute of Machine Building, or TsNIIMash, noted that nuclear explosions in space are currently banned under the 1967 Outer Space Treaty. “If the asteroid threat becomes a question of serious damage, or even the very existence of life on Earth, these prohibitions would of course disappear,” TsNIIMash’s report said.
It’s no secret that the United States and Russia have talked about using nuclear weapons against dangerous asteroids, but Lu and his colleagues hope it doesn’t come to that. “Let’s find asteroids early so we don’t need to use the risky nuclear option,” the B612 Foundation said in a tweet.
If a threatening asteroid is detected early enough, there are a range of options available, such as stationing a gravitational tractor near the space rock to pull it ever so gradually into a benign orbit … or hitting it with impactor spacecraft to push it out of harm’s way. Scientists are proposing space missions such as NEOTwIST and AIM to find out which of those concepts work best for various situations.
