Should eris , and many other objects circling the sun beyond neptune 's orbit ?
厄里斯和许多其他在海王星轨道绕着太阳转动的天体，又该不该是行星呢？
The scientist who discovered eris , caltech astronomer mike brown , thinks pluto 's demotion was the right move .
发现厄里斯的科学家加州理工学院的天文学家mikebrown认为，冥王星的降级是正确的。
Those new rules cast pluto out , and put it in a new , and very exclusive , club of just five confirmed dwarfs in the solar system : pluto , ceres , haumea , makemake and eris .
Astronomers had found at least three new objects that were as big as pluto ( quaoar , sedna and eris ) , and the international astronomical union needed to find a new way to classify exactly what makes a planet a planet .
