Sedna good as 'planetoid'
(China Daily)
Updated: 2004-03-17 23:27

Chinese astronomers believe the discovery of Sedna earlier this week merits a discussion on what criteria are used in naming a planet.

Astronomers in the United States announced on Monday they had discovered the most distant object ever found in the solar system, and named it Sedna after an Inuit goddess.

Both Mike Brown, who led the research team at the California Institute of Technology, and Brian Marsden, director of the Minor Planet Centre of the International Astronomical Union, have doubted Sedna is a planet and called it a "planetoid."

But some other astronomers have spoken out with their guess that Sedna may be our solar system's 10th planet.

Chinese astronomers have responded in general that it is almost impossible for Sedna to be the 10th planet, according to a report on Wednesday's Beijing Morning Post.

Li Jing, a professor and researcher with the National Astronomical Observatories, as saying that both Sedna and Pluto should both be regarded as larger cosmic bodies belonging to the Kuiper Belt.

Li said a "historical error" had already been committed when Pluto was named the ninth planet in the solar system.

Sedna is a frigid world -- some 240 minus C -- with a similar structure to Pluto's. Scientists say that if it is a planet, it is the coldest object ever found in the solar system.,

Zhu Jin, director of Beijing Astronomical Observatory, agreed with Marsden. He was quoted by the newspaper as saying the object should be designated a "planetoid," and is only one of the countless cosmic bodies belonging to the Kuiper Belt.

Usually planets travel in a rather round path around the sun, but Sedna, which is much smaller than planets in the solar system, is found to travel in a highly elliptical path which takes 10,500 years, Zhu said. Sedna is 13 billion kilometres from the sun.

With all the debate among astronomers, a final decision should be made by the International Astronomical Union, which usually takes a couple of decades to decide such matters, according to Professor Qi Rui, an astronomer.

Qi said there have been several other claims of discoveries of a another planet in the solar in the past few years.

But such discoveries take a long time to confirm and gain public recognition, Qi said.

Close

Today's Top News     Top China News
Pakistanis may be near bin Laden's aide al-Zawahri         Government relaxes control of airfares, finally         U.S. launches WTO complaint against China         Report: China, Iran sign US$20b gas deal         FM to pay official visit to DPRK         women bosses urged to date and marry	FM to pay official visit to DPRK       As kids keep on calling, experts worry       Gov'ts urged to clear up payments in arrears       Sino-US trade advances amid problems       Police website builds bridges to community       Drought worsens capital water crisis