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April 9, 2001

ONLINE EXCLUSIVE
COLUMN

What Sticks:
The truth is up there

By Wendy Wolfson (wendy@wolfsonpr.com)

More "What Sticks" Columns:

Nerd Gladiators Face Off, Save America

Wendy Wolfson ll eyes turned to the sky when the Soviet-era MIR Space Station recently descended from orbit into an unpopulated part of the Pacific Ocean. According to AP reports, scientists predicted that about 27 tons of Mir parts could possibly survive atmospheric immolation to plummet to the earth's surface.

Only one person on earth has ever been reportedly hit by stuff falling from space. In January 1997, a woman in Tulsa, Okla., escaped injury despite being grazed by a bit of metal mesh falling from the sky, debris from an upper-stage U.S.-made Delta rocket used to put a Global Positioning System satellite in orbit almost a year earlier. That same day, in Georgetown, Texas, a farmer's wife told her husband that something that looked like an "upside-down rhinoceros" had just plunked into their yard. It was the rocket's 580-pound stainless-steel tank that missed their house by a scant 50 yards and a major highway by another 150 yards. According to NASA's computer modeling, Delta second-stage components, engineered for durability, are expected to survive reentry every single time their host disintegrates.

While alien spaceship sightings are popular in the public's imagination, they really are much less common than incidents of our own trash falling from the sky. As we increasingly become electronically interconnected in the information age, we depend on a plethora of communications satellites to do things like make phone calls from our plane seats and tune into our favorite TV programs.

More troubling than the infrequent rain of Volkswagen-sized chunks of hot metal is the junk still circulating round our global "hood."

Space garbage, or the scientific euphemism "orbital debris" includes satellites gone bad, sections of booster rockets, bolts, hatches blown off space modules, and bits of chipped paint. Pieces and parts of our satellites and rockets will stay in orbit for millennia or at least until they hit something else orbiting in space, and further fragment into smaller pieces of scrap to whiz around the earth ad infinitum.

Our space program is a marvel of sophisticated engineering and information technology. Perhaps the more complicated and elaborate our computing edifices get, the more vulnerable we are to choking on our own trash.

Call it the "oops" factor.

Our aspirations to the stars could very well be stymied not so much by the restrictions of distance and time, but by the dubious realization that we can't even launch a shuttle out of our front driveway without encountering a steady stream of dangerous orbiting junk 400 miles up. In 40 years of the space program, we've become more sophisticated at putting things up in the sky, but we still haven't quite figured out how to neatly get them back.

In the past year or so, flight controllers have had to rotate the International Space Station (ISS) at least twice to avoid possibly catastrophic collisions with known orbiting junk. Even the venerable Space Shuttle regularly changed its orientation so that threatening debris would hit on the rear, rocket side, instead of striking the crew compartments or an astronaut on a space walk. Each successive decade the ISS is in orbit, according to computer models, it has about a 20% chance of sustaining a "critical penetration."

A large enough piece of debris colliding with the space station at a typical speed of about six miles a second could conceivably implode a pressurized crew module. MIR was intermittently hit by debris large enough to dent the inner wall of the crew compartment. Unlike a pebble crashing toward a car windshield at 60 mph, by the time a fleck of junk appears on the horizon, it strikes too quickly for any evasive maneuvering.

NASA is also developing in-flight repair kits for plugging up larger holes. Duct tape played a critical role in bringing Apollo 13 back to port. Perhaps every shuttle astronaut in the future will be presented with a lunch bag, a roll of duct tape, a caulking gun for larger holes, and hearty well wishes from Mission Control.

One of the first known pieces of space junk was astronaut Ed White's glove floating off during a space walk back in the '70s. Using radar, Earth-bound site operations staff were able to track the glove until it burned up in the atmosphere.

NASA is currently using a variety of sophisticated telescopes and computer-modeling simulation programs to track over 9,500 objects of space debris, melon-size or greater; there may be up to 120,000 items 1 centimeter in size or greater orbiting Earth! The number of particles smaller than 1 centimeter, such as paint flecks, probably exceeds the tens of millions.

Repurposed Cold War technology tracks some objects visually, others by microwaves, and still others by radar stations such as Norway's Arctic Globus II, a few miles from Russian military bases on the Kola Peninsula. The latest Satellite Situation Reports compiled by the NORAD (North American Air Defense) facility at Cheyenne Mountain, Colo., lists an average of 20,000 observations of "uncorrelated targets," otherwise known as space junk, made each day.

Within the past four decades of space exploration, we've already left our mark on the environment and few of the objects display "Property of..." tags. Note the origins of the known junk: The United States almost wins! By the time they get here, would the alien explorers of the future find our planet only a buzzing junk heap? Even if we aren't alone in the universe, due to distance and time considerations, our entire civilization could come and go before extraterrestrial intelligent beings even know we exist.

ORBITAL BOX SCORE
(as of December 27, 2000)

Country /
Organization Payloads Rocket Bodies And Debris Total

China 32 338 370

CIS 1331 2553 3884

ESA 30 238 268

India 20 5 25

Japan 66 45 111

United States 936 2871 3807

Other 305 26 331

TOTALS 2720 6076 8796

Cataloged by U.S. Space Command

From the Orbital Debris Quarterly News

But look on the bright side: Maybe new forms of life will evolve from the trash we leave behind.

This concept of evolution was promoted in "Allegro Non Troppo" the satiric Italian knockoff of the Disney classic "Fantasia," in which new life on earth evolves from the backwash left in an empty bottle of Coca-Cola tossed into some celestial gutter. This does lead one to hypothesize about the theory that humans are "fertilizing" space, or even about the origins of our own species. Some think that life on earth comes from space bacteria or its by-products.

Nobody has yet come up with a workable solution for cleaning up the garbage. Zapping it with giant, high-powered laser beams to nudge it back into the earth's atmosphere to burn up has been proposed as a sort of cosmic depilatory. Unfortunately, this scheme is impractical from Earth due to its tremendous distance and power requirements.

Probably the best course for larger objects is a process known as de-orbiting, leaving a satellite or rocket enough of a fuel reserve to get it back into Earth's atmosphere, where it can self-incinerate after its task is done. This of course, doesn't address the errant paint flecks orbiting at 17,500 mph.

Of course, not only might the circulating space junk impede our travel more than the restrictions of relativity, but also the parts that don't burn up might end up unexpectedly adorning your front yard. Complaints about errant junk, if it appears to have fallen from the heavens, should be addressed to Michael Golightly, NASA-Johnson Space Center, Space Science Branch, or Michael.j.golightly1@jsc.nasa.gov.

Don't forget to check the municipal calendar taped to your fridge--is space junk pickup on every other Tuesday with the recyclables?