[meteorite-list] NASA Radar Reveals Asteroid 1998 QE2 Has Its Own Moon
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 30 May 2013 11:51:40 -0700 (PDT)
NASA Radar Reveals Asteroid Has Its Own Moon
Jet Propulsion Laboratory
May 30, 2013
PASADENA, Calif. -- A sequence of radar images of asteroid 1998 QE2 was
obtained on the evening of May 29, 2013, by NASA scientists using the
230-foot (70-meter) Deep Space Network antenna at Goldstone, Calif.,
when the asteroid was about 3.75 million miles (6 million kilometers)
from Earth, which is 15.6 lunar distances.
The radar imagery revealed that 1998 QE2 is a binary asteroid. In the
near-Earth population, about 16 percent of asteroids that are about 655
feet (200 meters) or larger are binary or triple systems. Radar images
suggest that the main body, or primary, is approximately 1.7 miles (2.7
kilometers) in diameter and has a rotation period of less than four
hours. Also revealed in the radar imagery of 1998 QE2 are several dark
surface features that suggest large concavities. The preliminary
estimate for the size of the asteroid's satellite, or moon, is
approximately 2,000 feet (600 meters) wide. The radar collage covers a
little bit more than two hours.
The radar observations were led by scientist Marina Brozovic of NASA's
Jet Propulsion Laboratory, Pasadena, Calif.
The closest approach of the asteroid occurs on May 31 at 1:59 p.m.
Pacific (4:59 p.m. Eastern / 20:59 UTC), when the asteroid will get no
closer than about 3.6 million miles (5.8 million kilometers), or about
15 times the distance between Earth and the moon. This is the closest
approach the asteroid will make to Earth for at least the next two
centuries. Asteroid 1998 QE2 was discovered on Aug. 19, 1998, by the
Massachusetts Institute of Technology Lincoln Near Earth Asteroid
Research (LINEAR) program near Socorro, N.M.
The resolution of these initial images of 1998 QE2 is approximately 250
feet (75 meters) per pixel. Resolution is expected to increase in the
coming days as more data become available. Between May 30 and June 9,
radar astronomers using NASA's 230-foot-wide (70 meter) Deep Space
Network antenna at Goldstone, Calif., and the Arecibo Observatory in
Puerto Rico, will perform an extensive campaign of observations on
asteroid 1998 QE2. The two telescopes have complementary imaging
capabilities that will enable astronomers to learn as much as possible
about the asteroid during its brief visit near Earth.
Radar is a powerful technique for studying an asteroid's size, shape,
rotation state, surface features and surface roughness, and for
improving the calculation of asteroid orbits. Radar measurements of
asteroid distances and velocities often enable computation of asteroid
orbits much further into the future than if radar observations weren't
NASA places a high priority on tracking asteroids and protecting our
home planet from them. In fact, the United States has the most robust
and productive survey and detection program for discovering near-Earth
objects. To date, U.S. assets have discovered more than 98 percent of
the known Near-Earth Objects.
In 2012, the Near-Earth Object budget was increased from $6 million to
$20 million. Literally dozens of people are involved with some aspect of
near-Earth object research across NASA and its centers. Moreover, there
are many more people involved in researching and understanding the
nature of asteroids and comets, including those objects that come close
to Earth, plus those who are trying to find and track them in the first
In addition to the resources NASA puts into understanding asteroids, it
also partners with other U.S. government agencies, university-based
astronomers, and space science institutes across the country that are
working to track and better understand these objects, often with grants,
interagency transfers and other contracts from NASA.
NASA's Near-Earth Object Program at NASA Headquarters, Washington,
manages and funds the search, study, and monitoring of asteroids and
comets whose orbits periodically bring them close to Earth. JPL manages
the Near-Earth Object Program Office for NASA's Science Mission
Directorate in Washington. JPL is a division of the California Institute
of Technology in Pasadena.
In 2016, NASA will launch a robotic probe to one of the most potentially
hazardous of the known Near-Earth Objects. The OSIRIS-REx mission to
asteroid (101955) Bennu will be a pathfinder for future spacecraft
designed to perform reconnaissance on any newly-discovered threatening
objects. Aside from monitoring potential threats, the study of asteroids
and comets enables a valuable opportunity to learn more about the
origins of our solar system, the source of water on Earth, and even the
origin of organic molecules that lead to the development of life.
NASA recently announced development of a first-ever mission to identify,
capture and relocate an asteroid for human exploration. Using
game-changing technologies this mission would mark an unprecedented
technological achievement that raises the bar of what humans can do in
space. Capturing and redirecting an asteroid will integrate the best of
NASA's science, technology and human exploration capabilities and draw
on the innovation of America's brightest scientists and engineers.
More information about asteroids and near-Earth objects is available at:
http://neo.jpl.nasa.gov/ , http://www.jpl.nasa.gov/asteroidwatch and via
Twitter at http://www.twitter.com/asteroidwatch .
More information about asteroid radar research is at:
More information about the Deep Space Network is at:
DC Agle 818-393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
agle at jpl.nasa.gov
Received on Thu 30 May 2013 02:51:40 PM PDT