Galactic Traveler Dropping In
In case you haven't already heard, we're getting an unusual
visitor late Tuesday night... no, it's not Aunt Mabel. With
asteroid 2007 TU24 making its closest Earth approach in more than
2,000 years, scientists and space enthusiasts alike are lining up
to get a good look at our visitor.
Scientists at NASA's Jet Propulsion Laboratory in Pasadena, CA
have just obtained the first radar images of asteroid 2007 TU24
using high-resolution radar data. The data indicate the asteroid is
somewhat asymmetrical in shape with a diameter of roughly 800
A rock of that size would create a major blast if it hit the
Earth, but scientists at NASA's Near-Earth Object Program Office at
JPL determined there is no possibility of an impact with Earth in
the foreseeable future.
Objects of this size don't come near Earth very often. The
asteroid Apophis is expected to fly closer to Earth in 2029 and
NASA detects and tracks asteroids and comets passing close to
Earth. The Near-Earth Object Observation Program, commonly called
"Spaceguard," discovers, characterizes and computes trajectories
for these objects to determine if they could be potentially
hazardous to our planet.
Asteroid 2007 TU24 was discovered by the NASA-sponsored Catalina
Sky Survey on October 11, 2007.
The first radar detection of the asteroid was acquired on
January 23, using the Goldstone 70-meter (230 foot) antenna. The
Goldstone antenna is part of NASA's Deep Space Network Goldstone
station in southern California's Mojave Desert.
The Goldstone 70-meter antenna is capable of tracking a
spacecraft traveling more than 10 billion miles from Earth. If that
isn't enough to boggle your mind, try this: The surface of the
70-meter reflector must remain accurate within a fraction of the
signal wavelength, meaning that precision across the
41,400-square-foot surface is maintained within one centimeter (0.4
On January 29 at 12:33 pm Pacific Time (3:33 am Eastern Time),
asteroid 2007 TU24 will pass within 334,000 miles of Earth - -
that's about one and half times the distance from the Earth to the
It will be visible in dark and clear skies through amateur
telescopes with a minimum three-inch aperture.
Have your telescope ready... and be glad this visitor isn't
coming to stay!