空间探测器是除卫星、宇宙飞船、航天飞机外的又一种航天器,它的目标是对深空中的天体(如恒星、行星、卫星、彗星等)进行探测。空间探测器离开地球时,必须获得足够大的速度才能摆脱地球引力,实现深空飞行。探测器沿着与地球轨道和目标行星轨道都相切的日心椭圆轨道(双切轨道) Space probes are another type of spacecraft besides satellites, spaceships and space shuttles. Its goal is to detect objects (such as stars, planets, satellites, comets, etc.) in deep space. When a space probe leaves Earth, it must obtain sufficient speed to get rid of the Earth’s gravity and achieve deep space flight. The detector follows a heliocentric elliptical orbit (tangent orbit) that is tangent to both the Earth’s orbit and the target’s orbit