But on April 18, the team saw several activedust devils leaving surprisingly bright tracks.
不过在4月18日，研究小组目睹了几场活跃的尘暴留下了令人惊讶的明亮痕迹。
2
Secondly, the probe could have an active radar or lidar defense that targets debris and uses lasers to vaporize the dust particles.
第二，探测器可能有主动雷达或者激光雷达防御系统，可以发现碎片，并用激光来汽化这些颗粒。
3
The team chose 140 active galactic nuclei, or AGNs, by selecting galaxies that emit a lot of X-rays, which can Pierce the galactic gas and dust that might otherwise block the nuclei from view.