This week, an international group of astronauts and legal experts met to consider a dire but hypothetical threat to life on earth: another massive asteroid impact, like the one that researchers believe ended the reign of the dinosaurs 65 million years ago. The group, the Association of Space Explorers (ASE), concluded their meeting by asking the United Nations to prepare an international response for when a dangerous object is detected heading towards our planet. Says astronaut Rusty Schweickart, who flew into orbit with the Apollo 9 mission: “Until we have a response in place, we’re as vulnerable as the dinosaurs” [The Register].
In the report, titled Asteroid Threats: A Call for Global Response, the team reminds the public of the asteroid Apophis, which gave humanity a brief scare in 2004 when researchers calculated that it had a 1 in 37 chance of hitting the earth in the year 2029. That calamitous prediction was soon refuted by further data on Apophis’ trajectory, but the new report notes that the asteroid, also known as a “near earth object” or NEO, has a 1-in-45,000 chance of striking Earth in 2036. Currently, NASA is watching 209 NEOs, none of which is considered to be dangerous. But a threat is likely to be detected within the next 15 years, according to the ASE. “New telescopes coming online will increase these discoveries by a factor of 100,” said Ed Lu, astronaut on space shuttle Atlantis [New Scientist].
Schweickart says that he doesn’t expect the United Nations itself to embark on any space missions to deflect or destroy asteroids, he just wants somebody to be in charge of making decisions about such undertakings. “When you have an asteroid threatening Earth, it’s uncertain where it’s going to hit until the last minute; the decision to take action has to be coordinated by the international community…. We’ve developed a program to get the international community prepared to make timely decisions so the technology we know we have can be used to protect life” [Scientific American].
Several proposals have been advanced in the past for ways to deflect an asteroid, including a concept released by the European Space Agency to send up a pair of spacecraft in what it called the Don Quixote mission; the spacecraft Hidalgo would barrel into the asteroid, while it partner, Sancho, would hover nearby to watch for a trajectory change. Meanwhile, the non-profit Planetary Society held a competition asking participants to design a mission to rendezvous with the asteroid Apophis and tag it with a monitoring device.
DISCOVER recently examined the threat from lurking asteroids and how they could be destroyed; read all about it in the article “What To Do Before the Asteroid Strikes.”