NASA space probe to slam into comet July 4

WASHINGTON (Reuters) - NASA's Deep Impact probe is scheduled to lob a big copper "bullet" into a comet on July 4 to look into the heart of this remnant from the formation of our solar system, scientists said on Thursday.
Impact is expected at 1:52 a.m. EDT (0552 GMT) on U.S. Independence Day.
About a day before the collision, the Deep Impact craft will send a 317-pound (144 kg) copper-fortified impactor toward comet Tempel 1, which will be about 83 million miles from Earth.
The impactor will steer itself toward the comet and the Deep Impact craft will pass about 310 miles away from it and watch the smash-up, the scientists said at a briefing.