Earth gets a rush of weekend asteroid visitors
US: An asteroid as big as a city block shot relatively close by the
Earth on Saturday, the latest in a series of visiting celestial objects
including an asteroid the size of a bus that exploded over Russia last
month, injuring 1,500.
Discovered just six days ago, the 460-foot long (140-meter) Asteroid
2013 ET passed about 600,000 miles (950,000 km) from Earth at 3:30 p.m.
EST (2030 GMT). That's about 2-1/2 times as far as the moon, fairly
close on a cosmic yardstick.
"The scary part of this one is that it's something we didn't even
know about," Patrick Paolucci, president of Slooh Space Camera, said
during a webcast featuring live images of the asteroid from a telescope
in the Canary Islands.
Moving at a speed of about 26,000 mph, (41,843 kph), the asteroid
could have wiped out a large city if it had impacted the Earth, added
Slooh telescope engineer Paul Cox.
Asteroid 2013 ET is nearly eight times larger than the bus-sized
asteroid that exploded over Chelyabinsk, Russia, on February 15.
The force of the explosion, equivalent to about 440 kilotons of
dynamite, created a shock wave that shattered windows and damaged
buildings, injuring more than 1,5000 people.
Later that day, another small asteroid, known as DA14, passed about
17,200 miles (27,680 km) from Earth, closer than the orbiting networks
of communications and weather satellites.
"One of the reasons why we're finding more of these objects is that
there are more people looking," Cox said.
Two other small asteroids, both about the size of the Russian meteor,
will also be in Earth's neighbourhood this weekend. Asteroid 2013 EC 20
passed just 93,000 miles (150,000 km) away on Saturday - "a stone's
thrown," said Cox.
On Sunday (yesterday), Asteroid 2013 EN 20 was expected fly about
279,000 miles (449,007 km) from Earth. Both were discovered just three
days ago.
"We know that the solar system is a busy place," said Cox.
"We're not sitting here on our pale, blue dot on our own in nice
safety ... This should be a wakeup call to governments."
NASA has been tasked by the U.S. Congress to find and track all
near-Earth objects 0.62 miles (1 km) or larger in diameter, and
estimates about 95 percent have been identified.
However, only about 10 percent of smaller asteroids have been
discovered, NASA scientists have said.
The effort is intended to give scientists and engineers as much time
as possible to learn if an asteroid or comet is on a collision course
with Earth, in hopes of sending up a spacecraft or taking other measures
to avert catastrophe.
About 100 tons of material from space hit Earth every day.
Astronomers currently expect an object about the size of what hit Russia
to strike the planet about every 100 years.
DECCAN HERALD
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