轻触贝努

2023年9月21日

Tagging Bennu
Image Credit: OSIRIS-REx, University of Arizona, NASA, Goddard Scientific Visualization Studio

Explanation: The OSIRIS-REx spacecraft’s arm reached out and touched asteroid 101955 Bennu on October 20, 2020, after a careful approach to the small, near-Earth asteroid’s boulder-strewn surface. Dubbed a Touch-And-Go (TAG) sampling event, the 30 centimeter wide sampling head (TAGSAM) appears to crush some of the rocks in this close-up recorded by the spacecraft’s SamCam. The image was snapped just after surface contact some 321 million kilometers from planet Earth. One second later, the spacecraft fired nitrogen gas from a bottle intended to blow a substantial amount of Bennu’s regolith into the sampling head, collecting the loose surface material. And now, nearly three years later, on Sunday, September 24, that sample of asteroid Bennu is scheduled to arrive on planet Earth. The sample return capsule will be dropped off by the OSIRIS-Rex spacecraft as it makes a close flyby of Earth. Twenty minutes after the drop-off, the spacecraft will fire its thrusters to divert past Earth and continue on to orbit near-Earth asteroid 99942 Apophis.

Tomorrow’s picture: reflections of the cosmos

轻触贝努
影像提供: OSIRIS-REx, University of Arizona, NASA, Goddard Scientific Visualization Studio

说明: 2020年的10月20日，OSIRIS-REx航天器小心翼翼的靠近小行星贝努满布巨石的表面，然后伸出机械臂轻触这颗小行星。在这个称为“轻触即走”（TAG）的采样事件里，宽30公分的采样头看似压碎了一些石块，如这幅由采样相机拍摄的影像所示。这张照片拍摄的时间点，是在离地球约3.21亿公里远的轻触表面事件发生之时。1秒钟后，航天器的气瓶喷出氮气，试图把大量贝努的腐岩吹入采样头，以收集它表面的松散物质。而在近3年后的9月24日（星期日），小行星贝努的样本预计会抵达地球。当OSIRIS-Rex航天器近距离飞越地球时，将投放样本返回舱。在投放样品的20分钟之后，这艘航天器将点燃推进器，绕过地球前去造访近地小行星阿波菲斯。 （101955 Bennu 贝努小行星；99942 Apophis 阿波菲斯小行星）

明日的图片: reflections of the cosmos