Following the fabulous success of NASA’s New Horizons mission to Pluto, the spacecraft continued out in the solar system making the first close flyby of a small Kuiper Belt Object (KBO), specifically 2014 MU69, nicknamed Ultima Thule.
On January 1, 2019, New Horizons came within ~3,500 km of MU69. This small KBO was discovered by members of the New Horizons team using the Hubble Space Telescope in 2014. MU69’s orbit identifies it as a cold classical KBO. This means it has probably been present at its current heliocentric distance (43 AU) and cold conditions for the past ~4.5 billion years. These cold conditions, combined with its small size, prevents it from maintaining a strong internal geologic engine to the present, making MU69 the most primitive body ever studied by any planetary spacecraft. Other than its orbital parameters and brightness, the only information known about Ultima Thule prior to observations by New Horizons were its red color, an approximate size (25-30 km diameter), elongated shape (derived by stellar occultations), and very dark surface (visible albedo estimate ~0.1).
In this talk, Dr. Bagenal will review the observations from New Horizon’s flyby of this small, distant object and their implications for understanding our solar system.