This is a time-lapse sequence compressing Hubble Space Telescope observations of Comet 2I/Borisov, spanning a seven-hour period. As the second known interstellar object to enter our solar system, the comet is moving along at a breakneck speed of 110,000 miles per hour. To photograph the comet Hubble has to track it, like a photographer tracking a racetrack horse. Therefore, background stars are streaked in the exposure frames. An artificial satellite also crosses the field of view. Hubble reveals a central concentration of dust around an unseen solid icy nucleus. Comet 2I/Borisov is only the second such interstellar object known to have passed through the solar system. In 2017, the first identified interstellar visitor, an object dubbed ‘Oumuamua, swung within 24 million miles of the Sun before racing out of the solar system.
Read the press release: https://hubblesite.org/contents/news-releases/2019/news-2019-53
Credit: NASA, ESA, and D. Jewitt (UCLA)