飞掠小行星Arrokoth

2019 November 18

Passing Asteroid Arrokoth
Video Credit: NASA, JHU APL, SwRI

Explanation: What would it look like to pass asteroid Arrokoth? The robotic New Horizons spacecraft zoomed past Arrokoth in January, 3.5 years after the spacecraft passed Pluto. If this object’s name doesn’t sound familiar, that may be because the distant, double-lobed, Kuiper-belt object was unofficially dubbed Ultima Thule until recently receiving its official name: 486958 Arrokoth. The featured black and white video animates images of Arrokoth taken by New Horizons at different angles as it zoomed by. The video clearly shows Arrokoth’s two lobes, and even hints that the larger lobe is significantly flattened. New Horizons found that Arrokoth is different from any known asteroid in the inner Solar System and is likely composed of two joined planetesimals — the building blocks of planets as they existed billions of years ago. New Horizons continues to speed out of our Solar System gaining about three additional Earth-Sun separations every year.

飞掠小行星Arrokoth
影像来源: NASA, JHU APL, SwRI

说明：从小行星Arrokoth旁边经过会是怎样的景象？新视野号宇宙飞船于今年一月飞掠小行星Arrokoth，距离它飞掠冥王星已经过去了三年半。如果这个天体的名字听起来不太熟悉，那可能是因为这颗之前被非正式的称为Ultima Thule的遥远、双瓣状柯伊伯带天体直到最近才被正式命名为486958 Arrokoth。这段精选的黑白视频动画是由新视野号飞掠Arrokoth时、从不同角度拍摄的影像制作而成。该视频清楚地呈现了Arrokoth的两个瓣状结构，甚至显示出较大的瓣状结构明显扁平。新视野号发现Arrokoth与内太阳系中的任何已知小行星都不同，它很可能是由两个连接在一起的星子构成，而这些星子是数十亿年前行星存在的基础。新视野号继续加速脱离我们的太阳系，每年大约增加三次地日分离。