by Playfuls Staff |
4th August 2006
University of Toronto astronomers have been trying to decide how to tell the difference between a small planet and objects like asteroids and comets. [more]
The question arose due to the discovery of what appears to be a companion planet of a tiny star called Oph1622, the New York Times reports.
The star is about 400 light-years from Earth and is so small that it never shown brightly, the astronomers say.
Examining a photograph of the star, they discovered a planet some 22 billion miles away that is about half as large as the star itself with a mass equal to seven Jupiters, according to a paper published on the Web site of the journal Science.
While the companion has the mass of a planet, confusion arises because it was born in the manner of stars, says the author of the paper, Dr. Ray Jayawardhana of the University of Toronto.
Scientists say planets form from the leftover gas and dust of stars.
Since it is impossible to roll the clock back billions of years, astronomers cannot be certain how some objects are formed.
That is why the debate continues over where to place the dividing line.
© 2006 UPI
