Makemake

Makemake is a dwarf planet in a faraway place called the Kuiper belt. The Kuiper belt is a ring of icy objects beyond the planet Neptune. Makemake is one of the biggest objects there and the fourth largest known object that orbits the Sun beyond Neptune. It was found in 2005 by astronomers Michael E. ("Mike") Brown, Chad Trujillo, and David Rabinowitz at Palomar Observatory.

Makemake is similar to the dwarf planet Pluto. Its surface is shiny and covered mostly by frozen methane, which gives it a reddish-brown color. Scientists think Makemake might have a hidden ocean of water under its surface because it shows signs of activity. It also has one known moon that has not been named yet. Because of its tilt, Makemake has very different seasons.

Because Makemake is very far from Earth, we cannot get close-up pictures of its surface. It looks like just a bright dot even through strong telescopes. Scientists would like to send a space probe to Makemake to learn more about it.

History

Discovery

Makemake was discovered in 2005 by a group of American astronomers including Michael E. ("Mike") Brown, Chad Trujillo, and David Rabinowitz. They were looking for big objects beyond the orbit of Neptune. They used a special camera on a telescope at the Palomar Observatory in California, United States. On March 31, 2005, they took pictures that showed Makemake, and a few days later, Mike Brown saw this very bright object in the pictures.

Before finding Makemake, the team had already discovered other large objects like Haumea and Eris, which were similar in size to Pluto. They planned to announce Makemake later, but had to do it earlier when another team claimed to have found Haumea first. Because of this, they announced Makemake in July 2005 together with Eris, which helped start discussions about what should be called a planet. This led to Pluto being classified as a dwarf planet in 2006.

Name and symbol

This dwarf planet is named Makemake after a creator and god of fertility from the myths of the Rapa Nui people from Easter Island. It was given the number 136472 by the Minor Planet Center on September 7, 2005. Before its official name, it was known by the temporary name 2005 FY₉ and had the nickname "Easterbunny" because it was found around Easter time.

Choosing the name was tricky because the astronomers wanted to keep its connection to Easter. They finally chose Makemake, which also followed the rule of naming objects in the Kuiper belt after creator gods. The official name was announced by the International Astronomical Union in July 2008.

A special symbol for Makemake was added to Unicode in January 2022. While scientists usually don’t use these symbols, some astrologers do. The symbol was designed to look like a traditional drawing of Makemake’s face, shaped like the letter “M”.

Orbit and classification

Makemake moves around the Sun at an average distance of 45.5 astronomical units, which is about 6.81 billion kilometers or 4.23 billion miles. It takes about 307 years to finish one full orbit. Its path around the Sun is not a perfect circle. It comes as close as 38.2 astronomical units to the Sun and goes as far out as 52.8 astronomical units.

Right now, Makemake is near its farthest point from the Sun, called aphelion. It will reach this point in May 2033. It is part of a group of icy objects called the Kuiper belt, which is beyond the planet Neptune. Makemake is the largest object in the classical Kuiper belt and is a dwarf planet. This is because it is big enough for its own gravity to shape it into a sphere, but not big enough to clear its orbit of other objects.

Size, shape, and mass

Makemake is almost round, with an average width of about 1,430 kilometers. This is about 60% the width of Pluto. It is the fourth-largest known dwarf planet in our solar system. Observations showed that Makemake is slightly flattened at the poles, with a width of around 1,420 kilometers there and 1,434 kilometers around the middle.

Makemake has a mass between about 2.5×10²¹ and 2.9×10²¹ kilograms. This makes it the fourth-most massive known dwarf planet. Compared to Earth's moon, Makemake has about 3.7% of its mass. Its surface gravity is much weaker than Earth's, about 3.6% of Earth's gravity.

Rotation

The time it takes for Makemake to spin once, called its rotation period, is not fully known. Scientists think it might be about 11.4 hours or 22.8 hours. They watch how Makemake’s brightness changes to figure this out.

Makemake’s brightness does not change much, so it is hard to measure its spin. We also do not know how much Makemake is tilted, but it might be tilted a lot. This could cause big changes in temperature and surface conditions, like on Pluto.

Geology

Makemake is a very cold object far from the Sun. It is so cold that some substances stay frozen like ice. Its surface is mostly covered in frozen methane, mixed with smaller amounts of other frozen compounds.

In visible light, Makemake looks very bright. It reflects about 82% of the sunlight that hits it — even brighter than Pluto. Scientists think the methane on its surface is fresh, and its appearance may change with seasons over many years. The surface looks fairly the same all over, without big differences in brightness or color, unlike Pluto.

Atmosphere or outgassing

Studies in 2025 found that Makemake has methane gas. This gas glows in a special kind of light because of sunlight. Makemake is the second object beyond Neptune known to have gas, after Pluto. Scientists do not know if this methane stays around Makemake as an atmosphere or if it is escaping from its surface for a short time.

If the methane stays as an atmosphere, it would be very thin—much thinner than Earth’s air and also thinner than Pluto’s. This thin atmosphere was not seen in older studies, which suggests Makemake might not have a thick atmosphere. Or, the methane might be escaping from the surface, possibly making a thin cloud around Makemake.

Satellites and potential rings

S/2015 (136472) 1

Main article: S/2015 (136472) 1

Makemake has one known moon, called S/2015 (136472) 1. It was found in pictures taken by the Hubble Space Telescope in 2015 and announced in 2016. This moon is much smaller and dimmer than Makemake, about 1,300 times fainter. It orbits Makemake in a circle and takes 18 days to go around the dwarf planet.

Possibility of other satellites

The Hubble Space Telescope has not found any other moons around Makemake that are bright enough to see. Bigger moons might be hidden if they are very close to Makemake.

Possibility of rings

Makemake does not have any known rings. Rings around faraway objects are hard to see directly. They are usually looked for when stars pass behind the object. No rings were seen when this happened for Makemake in 2011. If rings exist, they might be very small and hard to spot, or hidden in the same way as its moon. Some think small rings could exist but they would need special conditions to stay there.

Origin

Makemake, like other dwarf planets in the Kuiper belt, is thought to have formed early in the Solar System's history, about 4.5 billion years ago. These dwarf planets started as small pieces called planetesimals. Over time, they grew bigger by pulling in nearby material.

One theory suggests that Makemake may have formed closer to the Sun. The movement of the giant planets might have moved it to its current place. This change happened a few tens of millions of years after the Solar System formed.

Observation and exploration

Makemake looks very bright because it is big and its surface reflects lots of sunlight. You can see it with a strong telescope when it is closest to Earth. Even though it is bright, it was found later than many dimmer objects because its path around the Sun is tilted and hard to see.

Scientists want to send a spacecraft to Makemake to learn more about it. Some ideas suggest a spacecraft could reach Makemake in about 16 years if it uses the gravity of Jupiter to speed up. The New Horizons spacecraft looked at Makemake from far away in 2007 and 2017, giving us useful information about its surface.