SoylentNews

takyon [soylentnews.org] writes:

NASA's Hubble Space Telescope has been used to find a moon [nasa.gov] orbiting the dwarf planet Makemake [wikipedia.org]:

The moon — provisionally designated S/2015 (136472) 1 and nicknamed MK 2 — is more than 1,300 times fainter than Makemake. MK 2 was seen approximately 13,000 miles from the dwarf planet, and its diameter is estimated to be 100 miles across. Makemake is 870 miles wide. The dwarf planet, discovered in 2005, is named for a creation deity of the Rapa Nui people of Easter Island.

[...] The observing team used the same Hubble technique to observe the moon as they did for finding the small satellites of Pluto in 2005, 2011, and 2012. Several previous searches around Makemake had turned up empty. "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.

A moon's discovery can provide valuable information on the dwarf-planet system. By measuring the moon's orbit, astronomers can calculate a mass for the system and gain insight into its evolution. Uncovering the moon also reinforces the idea that most dwarf planets have satellites. "Makemake is in the class of rare Pluto-like objects, so finding a companion is important," Parker said. "The discovery of this moon has given us an opportunity to study Makemake in far greater detail than we ever would have been able to without the companion."

Original Submission