[meteorite-list] 2003 EL61, IN PERSON

From: Darren Garrison <cynapse_at_meteoritecentral.com>
Date: Tue Sep 19 22:33:20 2006
Message-ID: <p2a1h25j4ofjrjb5mu6rihirsbrjbieq5i_at_4ax.com>

On Tue, 19 Sep 2006 21:06:38 -0500, you wrote:

>
> All these high inclination objects have also provided
>a big boost to the "Sun's Companion Star" theories
>we all remember so well, like Nemesis. It still has its
>backers, and they're all elated. Of course, what they
>don't tell you is that you don't need a brown dwarf
>star to perturb disc objects in inclination; all you
>need is an Earth mass object at 1200 AU. The Outer
>Outer System is waiting to be discovered... I think.

Speaking of Nemisis...

Here's a solar system with one:

http://www.msnbc.msn.com/id/14910347/

Distorted solar system discovered
Researchers find brown dwarf with companion planet
By Jeanna Bryner
Staff Writer
Space.com


Updated: 4:35 p.m. ET Sept 19, 2006
Discovered just 11 years ago, a class of oddball "failed stars" continues to
baffle as well as enlighten astronomers. Now researchers have spotted for the
first time one of these failed stars, called a brown dwarf, with a companion
planet ? both orbiting a Sun-like star.

"This is the first brown dwarf that has been directly imaged in an extrasolar
planetary system," lead researcher Kevin Luhman of Penn State University told
SPACE.com.

The finding, detailed in the current issue of The Astrophysical Journal, sheds
light on these mysterious objects that blur the lines between a planet and a
star.

Brown dwarfs are too small to trigger the fusion of hydrogen that keeps stars
like our sun shining for billions of years. Instead, with masses up to 75 times
that of Jupiter, brown dwarfs slowly cool and fizzle out over tens of millions
of years.

Located within the constellation Pisces, the newly spotted object is called HD
3651 B. It is 50 times the mass of Jupiter and thus considered a T brown dwarf ?
the coolest of the two brown-dwarf categories. This slow smoldering releases
infrared light, which was detected by NASA's Spitzer Space Telescope.

One reason the dwarf stayed out of view until now, Lunham said, is its lengthy
distance from its planet partner, which the researchers spotted using the
Doppler method. This technique measures the wobbles of a star caused by the
gravitational tug of an orbiting object that otherwise can't be detected.

However, the method is limited: Whereas the planet orbits at a snug 0.3
astronomical units (AU) from the Sun-like star called HD 3651, the brown dwarf
resides at a distance of 500 AU. One AU is the distance between the Sun and
Earth.

Luhman said due to the brown dwarf's prolonged orbit time of more than a
thousand years and its miniscule gravitational effect on the star, Doppler was
unable to pick up the object.

The discovery helps to clear up a quandary. When astronomers discovered the
system's Saturn-sized planet in 2003, they didn't know the cause of its
elongated, elliptical orbit. Now they suspect the tug from the brown dwarf's
gravity could be partly responsible for stretching the planet's orbit.

"Other planets with elliptical orbits found around other stars with Doppler
observations may also have previously unseen, distant brown dwarf companions
that are perturbing their orbits," Luhman said.
Received on Tue 19 Sep 2006 10:33:02 PM PDT