Not Just Any Old Listserv Message

This isn't the type of listserv message one routinely receives:

IF HURRICANES WEREN'T ENOUGH TO WORRY ABOUT:  There is a growing concern among astronomers that an asteroid due to buzz Earth on April 13, 2029 could pass through what is called a "keyhole", causing it to alter its course and strike the planet seven years later.  A keyhole is a gravitational "sweet spot" which is about 2,000 feet wide.  If predictions are correct and the asteroid, known as "99942 Apophis", passes through the most probable keyhole at the time, then its orbit will shift in such a way to bring it back on a collision course with Earth in the year 2036.  Diverting the asteroid’s course by as little as a half mile before the year 2029 would likely be enough to alleviate the threat. NASA officials are studying the proposed diversion, which is well within the range of current technology to do.

Source: Compu-Weather listserv