10 Facts About the Dwarf Planet Haumea

Kevin Gill, Flickr // CC BY-2.0
Kevin Gill, Flickr // CC BY-2.0

In terms of sheer weirdness, few objects in the solar system can compete with the dwarf planet Haumea. It has a strange shape, unusual brightness, two moons, and a wild rotation. Its unique features, however, can tell astronomers a lot about the formation of the solar system and the chaotic early years that characterized it. Here are a few things you need to know about Haumea, the tiny world beyond Neptune.

1. THREE HAUMEAS COULD FIT SIDE BY SIDE IN EARTH.

Haumea is a trans-Neptunian object; its orbit, in other words, is beyond that of the farthest ice giant in the solar system. Its discovery was reported to the International Astronomical Union in 2005, and its status as a dwarf planet—the fifth, after Ceres, Eris, Makemake, and Pluto—was made official three years later. Dwarf planets have the mass of a planet and have achieved hydrostatic equilibrium (i.e., they're round), but have not "cleared their neighborhoods" (meaning their gravity is not dominant in their orbit). Haumea is notable for the large amount of water ice on its surface, and for its size: Only Pluto and Eris are larger in the trans-Neptunian region, and Pluto only slightly, with a 1475-mile diameter versus Haumea's 1442-mile diameter. That means three Haumeas could fit sit by side in Earth—and yet it only has 1/1400th of the mass of our planet.

2. HAUMEA'S DISCOVERY WAS CONTROVERSIAL.

There is some disagreement over who discovered Haumea. A team of astronomers at the Sierra Nevada Observatory in Spain first reported its discovery to the Minor Planet Center of the International Astronomical Union on July 27, 2005. A team led by Mike Brown from the Palomar Observatory in California had discovered the object earlier, but had not reported their results, waiting to develop the science and present it at a conference. They later discovered that their files had been accessed by the Spanish team the night before the announcement was made. The Spanish team says that, yes, they did run across those files, having found them in a Google search before making their report to the Minor Planet Center, but that it was happenstance—the result of due diligence to make sure the object had never been reported. In the end, the IAU gave credit for the discovery to the Spanish team—but used the name proposed by the Caltech team.

3. IT'S NAMED FOR A HAWAIIAN GODDESS.

In Hawaiian mythology, Haumea is the goddess of fertility and childbirth. The name was proposed by the astronomers at Caltech to honor the place where Haumea's moon was discovered: the Keck Observatory on Mauna Kea, Hawaii. Its moons—Hi'iaka and Namaka—are named for two of Haumea's children.

4. HAUMEA HAS RINGS—AND THAT'S STRANGE.

Haumea is the farthest known object in the solar system to possess a ring system. This discovery was recently published in the journal Nature. But why does it have rings? And how? "It is not entirely clear to us yet," says lead author Jose-Luis Ortiz, a researcher at the Institute of Astrophysics of Andalusia and leader of the Spanish team of astronomers who discovered Haumea.

5. HAUMEA'S SURFACE IS EXTREMELY BRIGHT.

In addition to being extremely fast, oddly shaped, and ringed, Haumea is very bright. This brightness is a result of the dwarf planet's composition. On the inside, it's rocky. On the outside, it is covered by a thin film of crystalline water ice [PDF]—the same kind of ice that's in your freezer. That gives Haumea a high albedo, or reflectiveness. It's about as bright as a snow-covered frozen lake on a sunny day.

6. HAUMEA HAS ONE OF THE SHORTEST DAYS IN THE ENTIRE SOLAR SYSTEM.

If you lived to be a year old on Haumea, you would be 284 years old back on Earth. And if you think a Haumean year is unusual, that's nothing next to the length of a Haumean day. It takes 3.9 hours for Haumea to make a full rotation, which means it has by far the fastest spin, and thus shortest day, of any object in the solar system larger than 62 miles.

7. HAUMEA'S HIGH SPEED SQUISHES IT INTO A SHAPE LIKE A RUGBY BALL.

haumea rotation gif
Stephanie Hoover, Wikipedia // Public Domain

As a result of this tornadic rotation, Haumea has an odd shape; its speed compresses it so much that rather than taking a spherical, soccer ball shape, it is flattened and elongated into looking something like a rugby ball.

8. HIGH-SPEED COLLISIONS MAY EXPLAIN HAUMEA'S TWO MOONS.

Ortiz says there are several mechanisms that can have led to rings around the dwarf planet: "One of our favorite scenarios has to do with collisions on Haumea, which can release material from the surface and send it to orbit." Part of the material that remains closer to Haumea can form a ring, and material further away can help form moons. "Because Haumea spins so quickly," Ortiz adds, "it is also possible that material is shed from the surface due to the centrifugal force, or maybe small collisions can trigger ejections of mass. This can also give rise to a ring and moons."

9. ONE MOON HAS WATER ICE—JUST LIKE HAUMEA.

Ortiz says that while the rings haven't transformed scientists' understanding of Haumea, they have clarified the orbit of its largest moon, Hi'iaka—it is equatorial, meaning it circles around Haumea's equator. Hi'iaka is notable for the crystalline water ice on its surface, similar to that on its parent body.

10. TRYING TO SEE HAUMEA FROM EARTH IS LIKE TRYING TO LOOK AT A COIN MORE THAN 100 MILES AWAY.

It's not easy to study Haumea. The dwarf planet, and other objects at that distance from the Sun, are indiscernible to all but the largest telescopes. One technique used by astronomers to study such objects is called "stellar occultation," in which the object is observed as it crosses in front of a star, causing the star to temporarily dim. (This is how exoplanets—those planets orbiting other stars—are also often located and studied.) This technique doesn't always work for objects beyond the orbit of Neptune, however; astronomers must know the objects' orbits and the position of the would-be eclipsed stars to astounding levels of accuracy, which is not always the case. Moreover, Ortiz says, their sizes are oftentimes very small, "comparable to the size of a small coin viewed at a distance of a couple hundred kilometers."

LEGO Built a Life-Sized Astronaut Model to Celebrate the 50th Anniversary of Apollo 11

The LEGO Group
The LEGO Group

The LEGO Group is honoring the 50th anniversary of the Apollo 11 mission in a way that only LEGO can: with a life-sized astronaut model constructed entirely from LEGO blocks.

The 6-foot-3-inch model matches the space suit worn on the Moon by astronaut Edwin “Buzz” Aldrin on July 21, 1969, down to the American flag patch on his left shoulder. The front of the helmet even mimics the well-known photo of Aldrin standing on the Moon’s surface, with his helmet reflecting his own shadow and fellow Moon-walker Neil Armstrong in the near distance.

The feat took a team of 10 designers and LEGO Master Builders 300 hours and 30,000 LEGO bricks to complete, and you can see it in person on Washington, D.C.’s National Mall as part of the Smithsonian’s National Air and Space Museum’s Apollo 50 Festival from July 18 to July 20.

Though the astronaut model is already complete, there’s still tons to build—during the festival, you can help Master Builders assemble mosaic backdrops of the Moon and Mars, and you can even lend a hand in the construction of a 20-foot-tall replica of NASA's Space Launch System rocket, the vehicle NASA is developing to potentially use to send humans to Mars in the future.

The LEGO Group is also displaying an 11-foot-tall replica of a rocket at the Ontario Science Centre in Canada from now through September 2. It contains not only an impressive 80,000 bricks, but also built-in lights, sound, and a fog machine to simulate a rocket launch.

Buzz Aldrin on the Moon
Buzz Aldrin walks on the Moon.
NASA, Wikimedia Commons // Public Domain

It’s all part of a LEGO initiative to inspire a new generation of children to be enthusiastic about—and personally involved in—the future of space exploration. In addition to its brick-based efforts, the company is currently partnering with Scholastic on a program to send 50 kids to NASA Space Camp next year. “We will continue to inspire children to dream about what’s possible and to grow up to pursue STEM careers, said Bettina Inclán, associate administrator for communications at NASA’s Washington, D.C. headquarters.

Check out LEGO’s space-related collections—featuring Mars exploration, women of NASA, a recreation of the Moon landing, and more—on its online store.

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A Half-Blood Thunder Moon Will Light Up Tonight’s Sky

Matt Cardy, Stringer/Getty Images
Matt Cardy, Stringer/Getty Images

Today, July 16, 2019, marks 50 years since NASA launched the Apollo 11 lunar mission. In case you needed another reason to look up at the sky on this date, tonight's Moon will be a special one. It's the only full moon of July, and in some parts of the world, it will appear partially eclipsed, making for a rare half-blood thunder moon, according to Space.com.

The meaning of the name thunder moon has nothing to do with lightening and storm clouds. The full moon of each month of the calendar year is given a special nickname from folklore. January's is a wolf moon, March's is a worm moon, and June's is a strawberry moon. The full moon that appears in July is commonly called a thunder moon, because thunderstorms are frequent this time of year, but it can also be referred to as buck moon because July is when deer antlers are at their fullest.

There's another factor that makes tonight's Moon worth watching. Starting at 2:43 p.m. EDT, the Moon will enter a partial lunar eclipse. That means part of the full moon will pass through the shadow of the Earth, making one section of it appear darker than the rest. A full lunar eclipse is known as a blood moon due to the reddish hue it takes on in our planet's shadow. Tonight's event isn't a full eclipse, so it's being called a half-blood moon even though it may not take on a coppery tone. The partial lunar eclipse will reach its peak at 5:30 p.m. EDT, and conclude at 8:17 p.m. Unfortunately that means the eclipse won't be visible from the U.S., but spectators in Europe, Africa, South America, and parts of Asia will get to see the full show.

July is shaping up to be an exciting month for stargazers. On July 9, Saturn reached opposition, making it look especially large and bright in the night sky. The planet is no longer at peak visibility, but it will be easy to spot with the naked eye from now through September. If you're already planning at looking up at the Moon tonight, here's how to find Saturn at the same time.

[h/t Space.com]

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