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年
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月
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日,我国第一颗火星探测器“天问一号”在椭圆环火轨道历经约
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小时飞行后进入火星大气,经过约
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分钟的减速、悬停避障和缓冲,成功软着陆于预选着陆区。着陆巡视器
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包括“祝融号”火星车及进入舱
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与环绕器分离约
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分钟后,环绕器进行升轨,返回停泊轨道,为着陆巡视器提供中继通信。下列说法正确的是( )
- A、天问一号在椭圆环火轨道上受到非平衡力的作用,从远地点向近地点运行时,动能减小,势能增大
- B、天问一号进入火星大气后利用降落伞减速着陆,是为了减小探测器的惯性
- C、由于火星表面有大气存在,故可以利用超声波来实现地火通信
- D、两器分离后,环绕器在升轨的过程中,“祝融号”相对于它是运动的