- Astronomers in Hawaii report discovering
a new asteroid with an orbit completely within that of the Earth. It doesn't
pose a danger itself, they say, but it does point to a new place to look
- "All other efforts to discover asteroids
on a collision course with the Earth are being directed at a region of
the sky almost opposite the Sun," said David Tholen, planetary astronomer
at the Institute for Astronomy, in a statement.
- Previously, all known asteroids traveled
in an orbit farther from the Sun than the Earth over at least a portion
of their journey.
- "The significance of this discovery
is that we would have otherwise never found this new asteroid because it
apparently doesn't travel to that region of the sky being scanned by other
search efforts," Tholen said.
- Tholen and graduate student Robert Whiteley
made the observation using a specialized camera fitted on the University
of Hawaii's 2.24-meter telescope atop Mauna Kea last February.
- The asteroid, thought to be about 132
feet in diameter, has since been designated 1998 DK36.
- The exact size and shape of its orbit
remain uncertain, according to Tholen. However, the orbit's farthest point
from the Sun could be determined relatively accurately, and it appears
to be very close to, but slightly inside the orbit of the Earth.
- Could it collide with the Earth?
- "We were unable to obtain enough
observations to perform a formal probability calculation, though the best-fitting
orbit has the object passing an apparently safe 750,000 miles from the
Earth's orbit," said Tholen.