May 20, 2019

20.04.10: Hubble Smashes KBO record.

The Hubble Space Telescope has shattered yet another record; the smallest Kuiper Belt Object yet recorded. But the discovery came not from the telescope’s main optical array, but an unlikely source; its Fine Guidance Sensors. These star trackers point the HST and sample target stars 40 times a second. Using an innovative technique, a team led by Hike Schlichting sifted through 4.5 years of data to find a single 0.3 second in duration event. This is estimated to be a tiny KBO inclined about 14° degrees to the solar ecliptic. At an estimated 975 meters across and 6.8 billion kilometers distant, this object stands as the tiniest distant object ever detected. The Kuiper belt is a ring of icy material extending just beyond the orbit of Neptune out to about 55 astronomical units. At an estimated +35 magnitude in brightness, this icy body is far too small for even Hubble to see. The object was inferred indirectly by what’s known as a stellar occultation. This discovery also highlights the utility of pouring over the backlog of astronomical data generated by such platforms as Hubble. What other discoveries lay hidden it that thar’ data?