The 10^th Planet Sedna

With all of our interest in space over the years, and with the advancement of modern telescopes, it seems incredible that we have only recently discovered a tenth large globe on the fringe of our solar system.

The debate is still on whether to welcome this newly discovered space body (named Sedna for an Alaskan Inuit ocean goddess), can be classified as a planet, a very large piece of space debris, or even a new class of astronomical objects.

People who deal with this stuff say Sedna is too small to be a planet since it is only 1,100 miles across. That makes it smaller than Pluto, which at 1,413 miles, also is contested as a real planet.

Brian Marsden, head of the International Astronomical Union's Minor Planet Center, said he believes Pluto is just one of thousands of rocky objects orbiting at the fringe of the solar system in a region known as the Kuiper Belt. That is about seven billion kilometers from Earth.

Sedna, with a 10,500-year-long elliptical orbit around our sun, is three times farther from Earth than Pluto, or an estimated 21 billion kilometers. That puts it way out in space in a hypothetical territory called the Oort cloud, a distant reservoir of icy comets that may extend as far as the next star.

Discovered in November, 2003 by a team led by Michael Brown of the California Institute of Technology, Pasadena, the little body maintains a 10,000-year orbit and offers a number of mysteries for astronomers to solve.

It lives in a part of the solar system that astronomers once thought was empty. Sedna is red and shines brighter than astronomers would expect in the outer solar system, which is in itself a mystery.

Sedna is even believed to have a tiny moon. Its surface temperature is estimated at about minus 400 degrees Fahrenheit making it the coldest known place in our solar system.

Brown noted that Sedna may be the most primordial object ever found. That is because it exists in a sparse region of space where it has escaped heating by the Sun and may have even avoided collisions with meandering space bodies.

Sedna was found by Caltech's Palomar Observatory near San Diego and later confirmed by other observatories, including NASA's new Spitzer Space Telescope.

Sedna is among a number of relatively large orbiting objects in existence in the Kuiper Belt. Among the other recent discoveries are 2004 DW, estimated to measure about 994 miles in width, and Quaoar, discovered in 2002 and measuring about 780 miles wide.

These new discoveries enhance the argument against allowing such powerful instruments as the Hubble space telescope to go to junk. Rather than spend massive amounts of money and resources to gain military superiority over the world, the human race would gain far more knowledge from the visual exploration these instruments can accomplish in our lifetime.