Will 2004MN4 be the next Y2K?Russell L. Schweickart, Apollo 9 astronaut and Chairman of the B612 Foundation presented a paper last week at the National Space Society International Space Development Conference in Washington, DC, calling for action to prevent Earth from colliding with an asteroid headed our way.
The asteroid in question, 2004MN4, will probably pass within 19,000 miles of Earth on April 13, 2029. This is an extremely close pass in astronomical terms. It will be closer than our own Geosynchronous communications satellites at around 24,000 miles out. This is scary enough, but the real problem may be after the asteroid changes course during the close fly-by. The 320 meter diameter rock may be re-aimed for a direct hit to Earth when it swings back around in 2036. That would give us only seven years to figure out how to deflect it.
We will not really know how much the path will change until it has already passed by the first time.
It turns out that it would take a million times more energy to change the direction of the asteroid after it passes us in 2029 than it would take before it got here. So, we have to decide to deflect the asteroid away from us long before it would ever get near us. Also, it is a pretty small rock and it may not really come that close to us in 2029 after all.
Schweickart is asking for a mission very soon to plant a transmitter on the asteroid so that we can keep better track of its heading. He calculates that even with low probabilities of a direct hit, we would still be saving money by spending a billion or so now. With more accurate trajectory information we can make better decisions in the future.
To me, this sounds like a good plan. We might as well spend space exploration money on preventing a disaster as on anything else.
The Deep Impact mission is scheduled to crash into a comet on July 4, 2005. My guess is that the data from this mission will give rise to more questions than answers. There will be a sort of space-rock exploration fever around that time. That would be a good time to push through a project to send off a mission to an errant asteroid.
PDF of Paper: A Call to (Considered) Action
UN position on Impact Events