Shooting stars may fill you with child-like wonder, but these celestial showstoppers are also reminders that Earth is hardly alone in space, and some of those cosmic objects can be downright dangerous.
The Perseid meteor shower, which appears every year in mid-August, occurs when Earth passes through a trail of debris left by Comet Swift-Tuttle. In 1973, based on calculations about the object's orbit using limited observations, astronomer Brian Marsden at the Harvard-Smithsonian Center for Astrophysics predicted that Comet Swift-Tuttle could collide with Earth in 2126. The catastrophic prediction was later retracted, but what would happen if Comet Swift-Tuttle smacked into our planet?
"We have to be clear that it's not going to happen," Donald Yeomans, a senior research scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, and author of "Near-Earth Objects: Finding Them Before They Find Us" (Princeton University Press, 2012), told Live Science. [Perseid Meteor Shower 2016: When, Where & How to See It]
When Swift-Tuttle was last seen in 1992, Yeomans was among those who produced revised models for the comet's motion, making the complicated calculations to account for the gravitational effects of the sun and planets on the space rock's orbit. The 1992 sighting, along with data from 1862 and 1737, provided astronomers with enough information to rule out the possibility of a collision in 2126. [Source: www.livescience.com]
Ещё видео!