I have a question concerning a comet that will pass by Earth in the year 2029. There has been speculation that the Earth’s gravity may alter its course and cause impact in the year 2036. Is this true? How is NASA tracking this, and what preparations are being made, if any?
The object you are asking about is not a comet; it is a small near-Earth asteroid named Apophis. It will come very close to the Earth in April 2009, and the Earth’s gravity will dramatically alter its orbit. There is a tiny possibility (less than one chance in 40,000) that the asteroid could then be on an orbit that would hit the Earth in April 2036. In 2013 Apophis will be within range of the Arecido radar, and that will produce a more accurate estimate of its orbit. I have discussed Apophis in several previous postings on this website, and you can also google it now that you know its name. Apophis is certainly interesting to scientists, and I just returned from an international meeting on defending the Earth against impacts, where we had considerable discussion of Apophis. I presented a paper there on a possible spacecraft mission to learn more about this asteroid. You can get lots more information on the NASA hazard website at (impact.arc.nasa.gov).
NLSI Intern Director
April 20, 2009