main asteroid belt

基本解释

It is the first probe to enter orbit around an object in the main asteroid belt between Mars and Jupiter .
它是为进入火星和木星之间的小行星带中环绕一个天体的轨道而进行的第一次探索。
The object, dubbed P/2010 A2, orbits the sun well within the main asteroid belt, according to observations taken as part of the Lincoln Near Earth Asteroid Research sky survey.
根据林肯近地小行星研究小组进行天空观测时所记录下来的观察资料， P/2010 A2 在小行星带主带内部围绕着太阳旋转。
huzhangao.blog.163.com
ScienceDaily (July 18, 2011) —NASA's Dawn spacecraft on July 16, 2011 became the first probe ever to enter orbit around an object in the main asteroid belt between Mars and Jupiter.
2011年7月16号，NASA的曙光探测器进入位于火星和木星之间的小行星带，成为进入这一地带的第一个探测器。

Although downward-looking diagrams of the Main Asteroid Belt make it look incredibly dense, the region has significant gaps, clumps and clusters.
FORBES: Main Asteroid Belt No Remnant Of Exploded Planet
Abell says the best estimates now are that the Russian object was initially a rocky silicate asteroid that almost certainly originated from the main asteroid belt.
FORBES: NASA Eager To Analyze Russian Meteor Fragments
But astronomers have been unable to figure out how they get from the main asteroid belt between Mars and Jupiter to the vicinity of the Earth.
ECONOMIST: Celestial mechanics