NASA says meteors become most visible when they collide with and streak across Earth's atmosphere.
By Paul McDougall
InformationWeek
August 11, 2009 04:00 PM
Stargazers across North America have their eyes to the sky this week to watch the Perseid meteor shower, an annual celestial display that hits its peak Tuesday and Wednesday. What many Earthbound observers may not know, NASA said, is that meteors are like big celestial bugs bouncing off the planet's "windshield," or atmosphere.
NASA said the Perseids could deliver up to 80 falling stars per hour, making it one of the liveliest meteor showers viewable from Earth.
"This week, lots of meteors will appear over Earth's northern hemisphere when our planet plows through a swarm of dust shed by periodic comet Swift-Tuttle," NASA explained. "It's the annual Perseid meteor shower, which peaks Aug. 11 and 12," the space agency added.
NASA likened a meteor shower to what happens when bugs hit the windscreen of a speeding vehicle. "Just as bugs tend to accumulate on the front windshield of a car, Perseids accumulate on the front windshield of Earth," said NASA.
NASA said Earth's windshield is, in fact, the atmosphere. "Earth's front windshield is the early morning sky. Earth circles the Sun dawn-side first, scooping up whatever lies on that side of the planet. That's why it's usually best to look for Perseids just before dawn," said NASA.
The space agency added that Perseids that strike glancing blows off the atmosphere are also worth checking out.
"Side windows, the ones to the left and right of passengers in cars, are good, too," said NASA. "Zooming down a bug-infested lane, side windows don't intercept many insects, but the ones they do gather are worth examining. Bugs that strike the side windows do so at a shallow angle, leaving long and colorful streaks," said NASA.
"A breathtaking Earthgrazer is the sort of meteor you're likely to remember for years," said NASA.作者: NuclearBlastLuv 时间: 12-8-2009 22:25
这边纬度太低应该看不到作者: azukayume 时间: 13-8-2009 09:27
应该看不到。。。。作者: evita811207 时间: 13-8-2009 18:21
看不到就好,还担心我错过了
