On the aspect of observation time, it has limited efficiency for low earth orbit target space-basedobservation, and good efficiency for high earth orbit observation.
在可见时间方面，天基空间目标光学监视系统对低轨目标的监视能力有限，而对高轨目标具有良好的监视性能。
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And the 1,000th world could be discovered surprisingly soon, as the space-based Kepler mission has already offered up hundreds of planet candidates that await further observation and confirmation.
And the 1, 000th world could be discovered surprisingly soon, as the space-based Kepler mission has already offered up hundreds of planet candidates that await further observation and confirmation.