Page 5 - Trashing the Planet: Examining Our Global Garbage Glut

A NASA illustration shows a research satellite orbiting Earth. The space around our planet
is filled with about one thousand operational satellites and about twenty-six hundred zombie
(nonoperational) satellites. If and when these vehicles crash into one another, they break apart
into thousands of pieces of space junk.

Vanguard 1 achieved the then-highest altitude of any space vehicle. It was
also the first solar-powered satellite.
Vanguard 1 collected information about Earth’s shape and gravitational
field. The satellite’s mission ended in 1965, when its solar-powered
communications system failed. But in the twenty-first century, Vanguard
1 is still in space, circling Earth once every 133 minutes. In 2008, on the
satellite’s fiftieth anniversary, the US National Aeronautics and Space
Administration (NASA) noted that the spacecraft had completed more
than 197,000 Earth orbits, traveling more than 6 billion miles (10 billion
km). Scientists calculate that the grapefruit-size Vanguard 1 will continue
to travel around Earth for another 240 years before finally falling from its
orbit and reentering Earth’s atmosphere.
ZOMBIES AND OTHER JUNK

Vanguard 1 is the oldest zombie (nonoperational) satellite traveling around
Earth, but it is certainly not alone. About twenty-six hundred zombie
satellites are orbiting Earth. And zombies make up just a tiny percentage
of all the human-made junk in space. Other junk includes nuts and bolts
dropped by astronauts on space walks; fragments of metal, glass, plastic,
and paint broken off from old satellites; and sections of rockets used to
launch space vehicles.
In 2016 scientists with NASA were tracking more than twenty-
three thousand pieces of orbital debris larger than 4 inches (10 cm)
across. Hundreds of thousands of pieces of debris are too small to track.
Whatever the size of the orbital debris, it travels fast—up to 4 miles (6.4
km) per second, or 17,500 miles (28,163 km) per hour. At this speed, even
the tiniest chip of paint can cause severe damage to working satellites.
When a 0.4-inch (1 cm) object traveling through space hits something,
the damage is equivalent to a 550-pound (249 kg) rock hitting a car
traveling at 60 miles (97 km) per hour. Such an impact can destroy crucial

SPACE JUNK 83