Friday, September 23, 2011

U.S. Target for Falling Satellite

By Douglas V. Gibbs

Death, taxes, and falling satellites. What goes up, must come down. Perhaps slower than originally thought, but a six and a half ton Upper Atmosphere Research Satellite (UARS) is falling to Earth, and at this point it looks like it may possibly descend somewhere above the United States.

The forecast was that the satellite would tumble out of the sky today, and miss North America entirely, but the descent of the craft from the heavens is moving slower than originally expected, and the vessel will probably enter our sky this weekend.

Chances are, according to NASA officials, that the entire spacecraft will burn up on re-entry, but the possibility that debris will survive and crash on American soil cannot be discounted. With the changing trajectory, no one seems to be entirely sure what the spacecraft will do.

If parts of the NASA spacecraft survives re-entry, NASA suggests those surviving pieces number up to twenty-six, the heaviest of those falling pieces of debris weighing about 300 pounds. However, the odds that one of those falling pieces of the satellite will strike Earth and cause injury are about 1 in 3,200. The chance of the chunk of debris actually striking a person is about 1 in several trillion.

NASA's falling satellite was originally launched in 1991 to study Earth's ozone layer and upper atmosphere. The satellite was decommissioned in 2005.

According to Space.com, "The sun has had an extremely active week, one that has included several solar flares. High solar activity can cause the Earth's atmosphere to heat and expand, which can increase drag on a low-flying satellite like UARS, making it fall faster."

Causing the Earth's atmosphere to heat? Is that an admission that global warming is not caused by man, but by the sun? - Oooops, sorry, just a thought. . . back to topic:

NASA does not have an exact determination where the satellite will finish its fall from space, but have determined the satellite will probably descend between the latitudes of Northern Canada and Southern South America, a region of Earth that encompasses much of the planet. The expectation is that they will be able to update their predictions with more certainty tonight.

Considering that three-quarters of the planet is covered by water, the likelihood that the satellite, if any of the debris escapes the heated descent, lands in the ocean is likely. But, at this point, where the debris from the satellite lands, if any survives the fiery fall, is anybody's guess.

UPDATE: Satellite may strike tonight, or early Saturday Morning - Southern California may have opportunity to see light show.

"As of 10:30 p.m. EDT on Sept. 23, 2011, the orbit of UARS was 85 miles by 90 miles (135 km by 140 km). Re-entry is expected between 11:45 p.m. Friday, Sept. 23, and 12:45 a.m., Sept. 24, Eastern Daylight Time (3:45 a.m. to 4:45 a.m. GMT). During that time period, the satellite will be passing over Canada and Africa, as well as vast areas of the Pacific, Atlantic and Indian oceans. The risk to public safety is very remote."

UPDATE: NASA said early Saturday it was trying to confirm the crash-landing of the biggest piece of US space junk to fall in 30 years, which was over Canada, Africa and open ocean during the re-entry window.

-- Political Pistachio Conservative News and Commentary

Huge Tumbling Satellite Could Fall to Earth Over US Tonight or Saturday, NASA Says - Space.com

Falling NASA Satellite Approaching Earth - CBS

Old NASA Satellite's Fall to Earth May Be Visible from Southern California - Space.com

Complete Coverage of NASA's Falling Satellite UARS - Space.com

NASA 'working to confirm' satellite touchdown - Yahoo News

No comments: