starship-design: Star Search Finds Neighborly Red Dwarf

["L. Clayton Parker" <lparker@cacaphony.net>]

Star Search Finds Neighborly Red Dwarf
By SPACE.com Staff
posted: 03:50 pm ET
20 May 2003



Astronomers have stumbled onto a previously unknown star in Earth's stellar
neighborhood, a red dwarf that appears to be the third-closest star system
to our own.

"Our new stellar neighbor is a pleasant surprise, since we weren't looking
for it," Bonnard Teegarden, an astrophysicist with NASA's Goddard Space
Flight Center, said in a written statement.

Teegarden, the lead author of the study, and his colleagues happened upon
the star while searching for nearby white dwarfs, the remains of collapsed
stars that quickly traverse the night sky. Astronomers track white dwarfs
like they track planets and near earth objects, by tracking their change in
position over time. The study of these dead stars can then help estimate the
mass and ages of galaxies.

"These and other stars make up the tapestry through which near earth
asteroids travel, which is our main concern," said Steven Pravdo, who
collaborated on the star search, during a telephone interview. Pravdo is the
project director for NASA's Near-Earth Asteroid Tracking (NEAT) program,
which supplied a database full of sky observations - originally meant to
find objects that might impact Earth - for Teegarden to sift through.

It was while going through the database that researchers discovered the dim
red dwarf, which shines about 300,000 times fainter than the Sun. It's
faintness has veiled it from astronomers until now, researchers said.

NASA astronomers estimate the newly discovered star to sit about 7.8 light
years from Earth towards the constellation Aries. The closest star to Earth
is Alpha Centauri, which is actually a set of triplets burning brightly
about four light years away. Barnard's Star, the next-nearest neighbor is a
slightly further hop at about six light years form Earth. One light year is
about six trillion miles (9.5 trillion kilometers).

U.S. Naval Observatory is currently taking more observations of the star to
pin down its exact distance from Earth. Teegarden's research on the red
dwarf will appear in the publication Astrophysical Journal, although a final
publication date has yet to be set.