For the first time ever, an astronomer has witnessed a comet changing the speed and direction of its own spin, thanks to newly analyzed Hubble Space Telescope photos. The unexpected reversal was triggered by "outgassing" jets that shot an icy mix of gas and dust into the solar system, according to a new study.
The comet, dubbed 41P Tuttle-Giacobini-Kresák (41P for short), was discovered by American astronomer Horace Parnell Tuttle in 1858, before being rediscovered by French astronomer Michel Giacobini in 1907 and again by Slovak scientist L'ubor Kresák in 1951 (hence its lengthy name). Comet 41P likely originates from the Kuiper Belt — the ring of asteroids, comets and dwarf planets beyond the orbit of Neptune — and likely spent the majority of its long life circling the sun on a timescale of decades to centuries.
