NASA's Hubble Space Telescope captured the comet 21/Borisov zooming through our solar system at a breakneck speed of 175,000 kilometers per hour. The first image shows the comet in front of a distant spiral galaxy; the galaxy's bright core is smeared in the image because Hubble was tracking the comet. This is important because knowing the size helps us to determine the total number, and mass, of such objects in the solar system, and in the Milky Way. Borisov is the first known interstellar comet, and we would like to know how many others there are.”According to scientists, 2I/Borisov may represent only the beginning of a series of discoveries of interstellar objects that visit our solar system. It's possible that there are thousands of such interstellar objects here at any given time; however, most of them are too faint to be detected with present-day telescopes.

Source: Fox News December 13, 2019 19:56 UTC