2025年4月25日
Asteroid Donaldjohanson
Image Credit: Lucy/NASA/Goddard/SwRI/Johns Hopkins APL/NOIRLab
Explanation: Main belt asteroid 52246 Donaldjohanson is about 8 kilometers long and 3.5 kilometers across. On April 20, this sharp close-up of the asteroid was captured at a distance of about 1100 kilometers by the Lucy spacecraft’s long range camera during its second asteroid encounter. Named after American paleoanthropologist Donald Johanson, discoverer of the Lucy hominid fossil, the elongated asteroid was likely formed about 150 million years ago from a gentle collision of two smaller bodies creating its characteristic contact binary shape. Launched in October of 2021, the Lucy spacecraft will continue its travels through the main asteroid belt in 2025, but is on its way to explore Jupiter’s swarm of Trojan asteroids. Lucy is expected to encounter its first Trojan asteroid target, 3548 Eurybates, in August 2027.
Tomorrow’s picture: light-weekend
唐纳德·约翰森小行星
影像提供: Lucy/NASA/Goddard/SwRI/Johns Hopkins APL/NOIRLab
说明: 主带小行星唐纳德·约翰森（52246 Donaldjohanson），长约8公里，宽约有3.5公里。在今年的4月20日，露西号探测器在1,100公里之外，用长距相机为这颗小行星拍下了这张清晰的特写影像，而这也是这艘探测器遇到的第二颗小行星。以南方古猿露西的发现者唐纳德·约翰森（美国古人类学家） 命名的这颗小行星，可能形成于1亿5千万年前，当2颗较小的天体发生了轻柔的碰撞，因此带着近接双天体特有的形状。发射于2021年10月的露西号探测器，在2025年中会持续穿过小行星主带，然后航向木星前去探索它的特洛伊群小行星。于2027年8月，露西号预期会遇到第一颗特洛伊小行星3548 Eurybates（欧律贝茨）。 （Donald Johanson 唐纳德·约翰森 唐纳德·,犹罕纳；Lucy spacecraft 露西号探测器）
明日的图片: light-weekend
