Astronauts to land on speeding asteroid by late 2020s
By Dick Pelletier
A lump of rock more than 40 meters in diameter speeding through
space at 28,000 mph, once considered the most dangerous object
in the universe, is about to become the site for humanity's next
"giant leap for mankind."
NASA engineers have selected asteroid
2000SG344 – which in 2000 was given a significant chance of
slamming into Earth with the explosive power of 750 Hiroshimas –
as the perfect space object to study. The operation would take
place before the 2030 Mars journey, a speculative trip bandied
about ever since the first President Bush mentioned in 1989 that
America should send men to the red planet.
The asteroid mission represents a crucial step
for America's space program. A report to be published next month
in the journal Acta Astronautica describes plans to use
the soon-to-be-developed Orion space ship for a three-to-six
month round-trip to the asteroid, with two explorers spending up
to two weeks on the rock’s surface.
As well as providing experience for longer Mars
trips, samples taken from the rock could help scientists convert
sub-surface ice into drinking water and breathable oxygen,
understand more about the birth of the solar system, and how
best to defend Earth against dangerous asteroid collisions.
Report co-author Rob Landis described the
mission's importance this way: "An asteroid will one day be on a
collision course with Earth. Doesn't it make sense to start
learning more about them? Our study indicates that we should do
this as soon as possible."
In 1980, only 86 near-Earth asteroids and comets
were known to exist. By 1990, the figure had risen to 170; by
2000, it was 921; and today the Jet Propulsion Laboratory places
the estimate at 5,388.
Asteroid collisions should not be taken lightly.
Experts recently discovered that an object 300 meters in
diameter hit Australia's Gulf of Carpentaria in 536 A.D. Landing
in water prevented the worst damage, but debris, dust, and gases
were still thrown into the atmosphere by the impact, which
blocked sunlight and temporarily cooled the planet. Byzantine
historian Procopius wrote of, "dim skies, cold summers, and poor
harvests in 536 and 537, and frost that covered China in the
summertime."
Earth has experienced several mass extinctions
from asteroid encounters. The dinosaurs died about 65 million
years ago; 96 percent of the world's marine species were zapped
250 million years ago; and around 10000 BC, woolly mammoths,
saber-toothed cats, and mastodons all disappeared.
Today, astronomers are nervously tracking 99942
Apophis, an asteroid with a slight chance of striking Earth in
April 2036, which could hit with 60,000 times the force of
Hiroshima – enough to destroy an area the size of France.
Aerospace Corporation's William Ailor believes that Earth has a
one-in-10 chance per century of a dangerous space-object strike.
Learning to control asteroids will provide
civilization with more safety, but there are other benefits
also. Asteroids maneuvered into orbit around Earth could be
mined for their treasure trove of minerals, and others could
become outposts to aid construction of space hotels and other
facilities.
Positive futurists believe that landing men on an
asteroid speeding through space will capture world imagination
as we head into this breathtaking "magical future."
This article appeared in various print publications and
on-line blogs. Comments always welcome.