/ 24 May 2005

Giant planet is twice the size of Jupiter

Astronomers have discovered a planet that is twice as big as Jupiter, the largest planet in our solar system, New Zealand researchers at the University of Auckland revealed on Tuesday.

They said the newly discovered planet is 15 000 light years away from the Earth, making it one of the most distant discovered to date.

With about twice the mass of Jupiter, it is twice as far from its solar-type star as the Earth is from the sun.

An Auckland University announcement said a scientific paper describing the event, written by 33 authors from 11 countries, has been submitted to the American Astrophysical Journal.

Professor Phil Yock, of the university’s faculty of science, said amateur stargazers and professional astronomers in a number of countries combined to discover the planet using a new variation of a fairly old technique called gravitational microlensing.

He said university researchers working as part of a New Zealand-Japanese collaboration called Microlensing Observations in Astrophysics (MOA) made key contributions, together with amateur astronomers at Auckland’s Stardome Observatory.

Yock also cited work by researchers at Princeton University and the University of California in the United States, Britain’s Jodrell Bank Observatory and New Zealand’s Mount John Observatory.

But he said the lead observations were made by Ogle, a Polish group based in Chile, crediting their principal investigator, Professor Andrzej Udalski, with ”a remarkable achievement”.

Yock said many other observatories around the globe made contributing observations that helped pin down the parameters of the planet. — Sapa-DPA