Star Points for October 2011 by Curtis Roelle
Space Junk

Several years ago on a warm summer night in June, I was at Piney Run Nature Center in 
Eldersburg.  The Westminster Astronomical Society was armed with telescopes for a public star 
party. The night was clear and the time was a few minutes before 11 p.m.

I was talking with my friend, Richard.  We were facing each other when he suddenly asked, "could 
you turn around and tell me what you think that is?" Turning around I saw three slowly moving 
glowing trails low in the northern sky traveling from left to right. The brightest object was glowing 
bright orange and leading the other two.  The faintest was also the slowest, trailing the other two.  It 
soon faded from view.

The two remaining objects continued across the sky while fading at the same time.  The color 
changed to blue, then gray, and then they disappeared behind a tree.  I didn't see the termination of 
flight, but it must have been spectacular.   I could hear the gasps of others who continued watching 
the amazing scene.

We suspected that it might have been a piece of returning space junk instead of a meteor.  
Meteoroid particles typically travel on the order of 10 to 40 miles per second with respect to the 
earth. Their smashing trips into the atmosphere usually last mere seconds at most.  By comparison, 
space vehicles are slower moving, traveling at around five miles per second.  The objects observed 
at Piney Run were moving much slower than a meteor. 

In the following days, news reports announced that it had been a re-entering Russian rocket booster.  
The rocket had been launched 12 years earlier and had silently bided its time orbiting Earth ever 
since.  It had re-entered and burned up in Earth's atmosphere somewhere between Maryland and 
Ontario, Canada (Canadian observers watched it in their southern sky).

The United States Strategic Command catalogs and tracks objects four inches across and larger in 
Earth orbit.  According to Air Force Space Command's professional journal High Frontier, as of 
last February there were 1,100 active satellites and 21,000 pieces of debris orbiting Earth.  As 
indicated in the opening paragraphs above, inactive derelict debris can be as large as a rocket 
booster.  These objects are tracked from the ground using telescopes, radar, and computers.  In 
addition the Maryland-built MSX satellite, developed at The Johns Hopkins University's Applied 
Physics Laboratory, tracks space junk from Earth orbit.

Last month a deactivated NASA satellite launched 20 years earlier in 1991 was making news.  The 
6.5-ton Upper Atmospheric Research Satellite (UARS) was dead hurtling weight looping around the 
earth 16 times a day. Drag from the few air molecules at the UARS' orbital height was pulling it 
down and soon it would plunge through the atmosphere in an uncontrolled reentry. Although most 
of the spacecraft would burn up in the atmosphere, the largest pieces, weighing several hundred 
pounds, were expected to survive and make it to Earth's surface over an area including six out of 
seven continents.

Using software and data available on the Internet, I calculated the final passes UARS would make 
over our area during its last hours (send an email for technical details, if interested).  Each pass was 
very low in the sky, skimming the horizon, with the satellite, in the shadow of the Earth, not directly 
visible.  But if it happened to re-enter and burn up while above our horizon in the sky, it would have 
been spectacular.  So I was prepared to observe and to photograph it.  Unfortunately, our skies were 
either cloudy or foggy on each of the three passes.  Yet fortunately, UARS apparently reentered 
harmlessly over the Pacific Ocean. 

It wasn't the first abandoned piece of unused space hardware to crash to earth, and it certainly won't 
be the last.  The 85-ton U.S. Skylab space station, having been abandoned years earlier, crash-
landed in Australia in 1979.  Salyut 7, a space station belonging to the Soviet Union, reentered in 
1991, its parts raining over Argentina.  A Soviet spy satellite crashed in Canada in 1978. Radiation 
from its reactor was spread over a wide area. Another nuclear-powered Soviet satellite crashed to 
Earth in 1983.

No human has ever been injured by falling man-made space debris.