Tag Archives: Space Debris

Some of the Satellites over Leiden

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THE BUSY-NESS OVER YOUR HEAD: Earth orbit is crowded with nearly a thousand operating satellites and tens of thousands of spent rocket engines, splinters from satellite collisions, and other space debris. Space is a busy place. This picture taken by expert satellite watcher Marco Langbroek frames some of the madding crowd over Leiden, the Netherlands:

“This single image of a 10×14 degree-wide part of the geostationary belt was taken near midnight of June 18-19 and shows 30 satellites,” says Langbroek. “Each black box contains one or more (mostly) geostationary satellites plus a few rocket bodies: 23 commercial geostationary satellites, one classified military geostationary satellite (Milstar 5), and 6 spent rocket boosters.”

“The geostationary belt can be seen as a slanting line of objects diagonally over the larger image.” he continues. “The geostationary belt (at declination -7.4 degrees for the Netherlands) never comes high in the sky for my country (which is at 52 N). All the objects on the picture have an elevation below 30 degrees. The image was taken from the center of Leiden–i.e. not an ideal dark sky. I did a slightly bad job in focussing, so the image is slightly less sharp (especially near the edges) than it could have been with this fine lens. Still, an amazing number of objects recorded in this small field of view!”

fr/spaceweather.com

UARS Satellite Falling Faster Than Expected

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NASA Satellite Falling Faster Due to Solar Activity

UARS to crash-land Friday, but no one yet knows where.

Fireball picture: Hayabusa reenters the atmosphere.

The sample capsule from Japan’s Hayabusa spacecraft became a fireball as it fell to Earth last June.

Photograph by Takashi Ozaki, Yomiuri Simbun/AP

Traci Watson

for National Geographic News

Published September 21, 2011

It may be doomed, but the NASA satellite that’s about to crash-land on Earthisn’t going out quietly. 

To scientists’ surprise, the six-ton Upper Atmosphere Research Satellite, or UARS, has picked up speed and is now expected to plummet through the atmosphere Friday.

Only two weeks ago government scientists projected that the satellite could return to Earth as late as the first days of October.

“The spacecraft is coming in a little faster than we’d originally anticipated,” said NASA orbital debris scientist Mark Matney. As a result, “it’s coming in sooner rather than on the later side.”

The satellite’s speed is due to a recent spike in the amount of ultraviolet rays being emitted by the sun, Matney said.

The radiation increase caused Earth’s atmosphere to expand, which increased drag on the satellite, causing it to fall faster.

A Thousand Pounds to Survive Reentry?

Experts predict that most of the UARS spacecraft will burn up in Earth’s atmosphere.

But more than 1,100 pounds (500 kilograms) of debris will probably survive the fiery plunge and slam down to Earth.

The biggest piece to reach the surface intact will most likely be a 300-pound (150-kilogram) piece of the spacecraft’s frame.

However, it’s still too early to know where the satellite’s components will land, Matney said.

The only tip scientists can give for now about the location of the “debris footprint” is that it will be somewhere between 57 degrees north latitude and 57 degrees south latitude—an area encompassing most of Earth’s populated land.

Odds of Debris Hitting You: 1 in 3,200

UARS, which collected data on Earth’s atmosphere from 1991 to 2005, was designed well before scientists started to worry about space debris.

to read more, go to:    http://news.nationalgeographic.com/news/2011/09/110921-nasa-satellite-uars-space-debris-crash-land-earth-nation/