by Ritvik Ravikiran and Timur Maryia
Image by NASA Hubble Space Telescope via Unsplash
'Oumuamua, whose origins are unknown, is regarded as one of the most unusual space objects discovered to date. Astronomers have been drawn to this asteroid from beyond our solar system for a long time. In 2017, 'Oumuamua was officially detected as the first interstellar object moving through the Solar System. Its intriguing Hawaiian name means "a messenger from afar arriving first" when translated. Given that it is the first of its kind, the name is pretty appropriate.
On October 19, 2017, astronomers in Hawaii using the Pan-STARRS1 telescope made the first observation of the object. When scientists originally announced on June 27, 2018, 'Oumuamua was believed to be a modestly active comet. Subsequent research, however, indicated that it was not an asteroid or comet and might instead be the residue of a fallen exocomet. After more studies showed no sign of a coma—the hazy cloud of gas and dust around a comet's core—the object was reclassified as an asteroid. Originally, it was thought to be a comet.
'Oumuamua's trajectory was quickly analyzed and it was found to be on a hyperbolic route, indicating that it originated from interstellar space. On September 9 the object streaked past the Sun, and on October 14 it passed within 15 million miles of Earth before completing its exit from the solar system. But what material makes up this enigmatic object? In November 2019, several astronomers speculated that it might be a "cosmic dust bunny" because of its extremely fluffy and light composition of ice and dust particles. But in August 2020, astronomers discovered that, contrary to previous suggestions, it is unlikely to be made of frozen hydrogen. All of these speculations notwithstanding, the composition of 'Oumuamua is still a mystery.
'Oumuamua has shed light on the genesis and evolution of planetary systems other than our own, notwithstanding its enigmatic nature. Its discovery provides proof that these kinds of interstellar objects exist and are detectable, despite their difficulty in being seen.
References
Anderson, P. S., & Anderson, P. S. (2019, November 27). Was ’Oumuamua a cosmic dust bunny? | Space | EarthSky. EarthSky | Updates on Your Cosmos and World. https://earthsky.org/space/was-oumuamua-a-cosmic-dust-bunny/
Scientists now think interstellar object ’Oumuamua might be a “dust bunny.” (2020b, September 10). New York Post. https://nypost.com/2020/09/10/scientists-now-think-interstellar-object-oumuamua-might-be-a-dust-bunny/?itm_source=parsely-api?itm_campaign=parsely_recommended_widget-3&itmMedium=site_widget&itmSource=parsely_recommended_widget&itm_content=widget_item-2
X, S. (2020, August 17). Scientists determine ’Oumuamua isn’t made from molecular hydrogen ice after all. https://phys.org/news/2020-08-scientists-oumuamua-isnt-molecular-hydrogen.html