Hubble just discovered the newest moon in the solar system, a tiny rock orbiting the dwarf planet Makemake, far beyond the orbit of Neptune.
The new moon is about 250 Km across, compared to the 1,400 Km wide Makemake. It orbits in approximately 12 days, and has an edge on orbit, making it difficult to spot. “Our preliminary estimates show that the moon’s orbit seems to be edge-on, and that means that often when you look at the system you are going to miss the moon because it gets lost in the bright glare of Makemake,” said Alex Parker of Southwest Research Institute, Boulder, Colorado, who led the image analysis for the observations.
The great thing about finding a moon is that we can use our understanding of gravity to determine the mass of the dwarf planet. It also contributes to the idea that most dwarf planets have a moon.
Pretty amazing that after 26 years, Hubble is still making incredible discoveries. I can’t wait for JWST to go up!