New planet definition could demote Pluto
Posted: Wed, Aug 23, 2006, 8:25 AM ET (1225 GMT)
Less than a week after astronomers proposed a definition for the term "planet" that could increase the solar system's total to at least 12, a new definition has emerged that could not only eliminate the three new planets but also the ninth planet, Pluto. After a contentious meeting Tuesday at the International Astronomical Union meeting in Prague Tuesday, astronomers came up with a revised definition for the term planet. The original proposal required planets to be orbiting a star (and not be in orbit around another planet) and be "nearly" round; the new definition retains those rules but adds that the planet be the "dominant object in its local population zone". Worlds that meet the first two criteria, but not the third—such as Pluto and Ceres—would instead be classified as "dwarf planets". IAU members are scheduled to vote on the proposed definition on Thursday.
Less than a week after astronomers proposed a definition for the term "planet" that could increase the solar system's total to at least 12, a new definition has emerged that could not only eliminate the three new planets but also the ninth planet, Pluto. After a contentious meeting Tuesday at the International Astronomical Union meeting in Prague Tuesday, astronomers came up with a revised definition for the term planet. The original proposal required planets to be orbiting a star (and not be in orbit around another planet) and be "nearly" round; the new definition retains those rules but adds that the planet be the "dominant object in its local population zone". Worlds that meet the first two criteria, but not the third—such as Pluto and Ceres—would instead be classified as "dwarf planets". IAU members are scheduled to vote on the proposed definition on Thursday.
Related Links:
| <<previous article | next article>> |
|
news in brief
|
|
Vast signs contract with SpaceX for ISS private astronaut missions
Posted: Sat, Dec 21 11:59 AM ET (1659 GMT) Avio signs ESA contracts for Vega upgrades and Earth science satellite launch
Posted: Sat, Dec 21 11:57 AM ET (1657 GMT) |
|
news links
|
|
Sunday, December 22
Rocket Lab launches sixth Synspective radar imaging satellite
Space News — 6:36 am ET (1136 GMT) SpaceX launches second mid-inclination rideshare mission
Space News — 6:36 am ET (1136 GMT) S. Korea successfully launches 3rd spy satellite into orbit
Yonhap News — 6:35 am ET (1135 GMT) HawkEye 360 Announces Successful Launch and First Contact with Cluster 11
HawkEye 360 — 6:31 am ET (1131 GMT) |
