Deep into the Kuiper Belt, the second brightest dwarf planet named after a deity of the Rana Nui people, completes its rotation every 7.77 hours, claiming its place in the vast outer space.

Makemake - known as the third largest trans-Neptunian object after Eris and Pluto - is initially believed to be moonless, but a discovery by NASA's Hubble Space telescope changes that.

Meet Makemake's Moon

NASA announced Wednesday that Hubble had detected a small, coal black moon around Makemake, distantly moving at approximately 13,000 miles (20,921 kilometers) away from the dwarf planet.

Hubble's observations were made in April 2015 with the help of its Wide Field Camera 3 (WFC3), allowing the telescope to view faint objects that are close to brighter ones.

Combined with the telescope's sharp resolution, Hubble's WFC3 helped scientists pick out the dark moon from Makemake's intense luminescence.

The dark moon, temporarily designated S/2015 (136472) 1 and nicknamed MK 2, is more than 1,300 fainter than the dwarf planet and has a diameter estimated to be 100 miles (160 kilometers) across.

To observe MK 2, the research team applied the same Hubble technique they used in searching for the small satellites of Pluto in 2012, 2011 and 2005. Previous investigations around Makemake had been unsuccessful.

Alex Parker, who led the image analysis for Hubble's observations, said preliminary calculations show that the dark moon's orbit appears to be "edge-on." This means that when scientists look at the system, the moon's presence can be missed because it gets lost in the luminous glare of Makemake.

Why Finding Makemake's Companion Is Valuable

Makemake's moon can offer astronomers important information regarding the dwarf planet system. By measuring MK 2's orbit, they can calculate mass for the system and eventually find clues into its evolution.

It also reinforces the theory that most dwarf planets possess satellites. Parker said Makemake is already in the league of rare Pluto-like objects, so searching for its companion is valuable because it will give them a chance to study the dwarf planet in far greater detail.

What's more, discovering the moon increases parallels between Makemake and Pluto - two icy dwarf planets covered in frozen methane.

"This new discovery opens a new chapter in comparative planetology in the outer solar system," said Marc Buie, leader of the research team.

Meanwhile, researchers will need more observations from Hubble to create accurate measurements to determine if Makemake's moon is circular or orbital. Initial calculations show that if the moon's orbit is indeed circular, it completes its revolution around Makemake for at least 12 days.

Determining the shape will also help settle the moon's origin.

If the moon is in an elongated orbit, it is likely an object from the Kuiper belt. If it is in a circular orbit, it means MK 2 is likely the product of a collision between another object in the Kuiper belt and Makemake. All of this would have occurred billions of years ago, when our solar system was relatively younger.

Watch the video about the discovery below.

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