NAU Astronomers Nix Asteroid for NASA Mission
Early this year, NASA announced a bold robotic mission to capture
an asteroid in a bag and return the rock to Earth orbit so it could be studied.
The mission could serve as training and testing for astronauts en route to an
eventual trip to the moon and Mars using the Orion spacecraft.
But a team of Northern Arizona University astronomers have shown
that the asteroid NASA has been using as a reference target (2009 BD) is not a suitable candidate. Using the Spitzer Space Telescope, the astronomers
showed that the space rock is just 10 to 13 feet in diameter. It would fit into
the average garage. They presented the research at the December 2013 meeting of
the American Geophysical Union in San Francisco and submitted it for
publication in the Astrophysical Journal.
diminutive size is likely too tiny to work as a target for the $2.6 billion
Asteroid Redirect Mission. The space agency has said it wants an asteroid
closer to about 20 feet across . . . . “We didn’t see it. It
was too faint to be detected in our data,” said David Trilling, NAU Assistant Professor of Astronomy. “We know it has to be
smaller than some size or we would have been able to see it.”
The researchers were
able to combine their own observations with what was seen of asteroid 2009 BD
when it squeaked between the Earth and the moon in 2011. . . . “Although we didn’t see it, we can constrain its properties quite
well,” said Michael Mommert, NAU post-doctoral researcher."This tells us something about the population
we knew nothing before about.” . . .
There are other
candidate asteroids, so Trilling said it is not a big deal for NASA to settle on one of the other 13
candidates on its published list. But those
too, have not been studied in
detail. . . . Mommert and Trilling
will look at the next asteroid on the list in February, named 2011 MD, to see
if it might be a suitable candidate.
--Eric Betz, article excerpted from the Arizona Daily Sun.