Taking The Measure of Makemake's Moon

We present the discovery and characterization of S/2015 (136472) 1, a satellite of the dwarf planet Makemake. The satellite was discovered in Hubble Space Telescope (HST) imagery collected in spring of 2015, found at a separation of 0.57" and ~1,300 times fainter than Makemake at the discovery epoch. The system was imaged in two visits separated by two days, and the satellite was visible in the first visit but undetectable in the second. Previous HST satellite searches also did not reveal S/2015 (136472) 1. Current observations constrain the satellite's orbit to be near an edge-on configuration, placing the system near a mutual event season. Follow-up observations will permit the measurement of Makemake's mass and density, as well as identify whether there is an upcoming mutual event season. We will discuss the current state of characterization of the system and its implications for Makemake's bulk, thermal, and surface properties, spin state, and the origin of S/2015 (136472) 1. Finally, we will address the current state of understanding regarding the population of dwarf planet satellites.