On March 31, 2005 Mike Brown, Chad Trujillo and David Rabinowitz made a discovery. It was an icy object nearly five billion miles from the Sun, out in the Kuiper Belt. Three years later the International Astronomical Union (IAU) listed it as a dwarf planet and it was named Makemake.

If you click on a link to an image, tap the back arrow on your browser to come back to the article.
How a dwarf planet got its name
If you discover a new small Solar System body, you report it to the IAU's Minor Planet Center. They give it a temporary identity – in this case, it was 2005 FY₉. When more observations confirmed the orbit, it got a minor planet number: 136472. It was then officially 136472 (2005 FY₉).

If you were on the team, would you want to say “one-three-six-four-seven-two-two thousand five-eff-wye-nine” every time you mentioned the new discovery? They didn't, and since they discovered it just after Easter, it got the nickname Easterbunny.

In 2008 the IAU made dwarf planets a new class of objects and “Easterbunny” was one of them. The discovery team also got to suggest a name – but not Easterbunny. The rules for naming objects like 136472 say that they must be named after creation gods. So the team chose Makemake. I know that looks like English make-make, but it's pronounced MAH.kay.MAH.kay. Makemake was a fertility god and the creator of humanity in the mythology of the Rapa Nui people of Easter Island.

Makemake's orbit
The Solar System is shaped like a disk with the Sun in the middle. The eight planets go around the Sun almost as if they were moving on a giant plate. We call this imaginary plate the ecliptic.

1. Makemake's orbit is tilted so the dwarf planet doesn't spend much time near the ecliptic.


2. When Makemake gets as close as it can to the Sun, it’s still 39 times farther away than we are. Astronomers call the distance from the Earth to the Sun one astronomical unit (au). So when it’s at its closest to the Sun it's 39 au away. It can be as far away from the Sun as 53 au.


3. A year on Makemake is 310 Earth years.

More about Makemake

1. Makemake is a dwarf planet, so you know it's small. It's about 1400 km across (less than 900 miles). You'd have to go around its equator three times to equal the distance across the United States from San Francisco to New York City.


2. Makemake seems to be covered in a layer of methane ice, mixed with some ethane and chemicals called tholins. Tholins give Makemake – and other icy bodies like Pluto – a reddish color.


3. Astronomers expected Makemake to have an atmosphere like Pluto does, but there doesn't seem to be one.


4. It's cold, about -239°C (nearly -400°F). The coldest Earth temperature ever recorded was in August 2010 in Antarctica: -94.7°C (-135.8°F).

Makemake has a moon
For ten years everybody thought Makemake didn't have a moon. But in 2015 astronomers using the Hubble Space Telescope found a small dark moon. It doesn't have a name yet. It's listed as S/2015 (136472) 1 and has been nicknamed MK 2. It seems to be about 175 km (110 mi) across and around 21,000 km (13,000 mi) from Makemake. They're still trying to work out how long it takes MK2 to orbit. All they can say so far is that it takes at least 12 days.

Is it dark on Makemake?

1. There isn't much light from the Sun reaching either Pluto or Makemake. This diagram shows how big the Sun would appear from different planets. It's just a dot on Neptune, which is closer to the Sun than the dwarf planets.


2. Pluto is between 30-49 au from the Sun and Makemake 39-53 au. For much of the time they're a similar distance from the Sun.


3. We have some idea about how dark it would be on Pluto from the New Horizons fly-by. NASA says, “if you stood on Pluto at noon you would have enough light to easily read a book.”


4. Since Makemake is brighter than Pluto perhaps you could also read a book there at noon.

If Makemake is so bright, why wasn't it discovered sooner?

1. Astronomers tend to search near the ecliptic and Makemake doesn't spend much time there.


2. When Clyde Tombaugh, the discoverer of Pluto, was searching the sky, Makemake was near the ecliptic. However it was lost in the middle of a large number of stars.