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 Is Launching an Official International Space Station Set

LEGO
LEGO

Not everyone can live out their childhood dreams of floating around in space aboard the International Space Station, but now you can at least construct a toy version of it for your own house.

Next month, LEGO is releasing an impressive model of the International Space Station as part of its Ideas program, which produces designs that were suggested by fans. This one was submitted three years ago by Christoph Ruge.

LEGO ISS
LEGO

According to TechCrunch, the kit includes the ISS, a dockable space shuttle, two astronaut figurines, and a satellite that you can “deploy” with the robotic Canadarm2 (which is used to capture and repair satellites on the ISS). It also comes with a display stand, so you can make it the eye-catching centerpiece of your coffee table if it happens to match your living room decor.

The ISS might not look as formidable as the life-size model of astronaut Buzz Aldrin that LEGO builders created last year, but that doesn’t mean it’s not difficult to construct—the 864-piece set is labeled for kids ages 16 and older.

LEGO ISS
LEGO

Having said that, it doesn’t mean that younger kids can’t help out with the assembly, or at least play with it once it’s complete. At about 7 inches high, 12 inches long, and 19 inches wide, the station could inspire the next generation of space explorers.

The $70 kit will be available on February 1 in LEGO stores or the LEGO website.

[h/t TechCrunch]

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A Snow Moon Will Light Up February Skies

makasana, iStock via Getty Images
makasana, iStock via Getty Images

February is the snowiest month of the year in many parts of the U.S., but on February 9, consider braving the weather outside to look up at the sky. That Sunday morning, the only full snow moon of the year will be visible. Here's what you need to know about the celestial event.

What is a snow moon?

If you keep track of the phases of the moon, you may already know that the full moon of each month has its own special name. Following January's wolf moon lunar eclipse is a snow moon in February. The name snow moon is said to have originated with Native American tribes, and it refers to the heavy snowfall that hits many parts of North America in February.

According to The Old Farmer's Almanac, different tribes had different names for February's full moon. The Wishram people named it the shoulder to shoulder around the fire moon and the Cherokee people called it the bone moon because animal bones were sometimes their only source of nutrition in the dead of winter. Snow moon is the name that's most commonly used by almanacs today.

When to See the Snow Moon

The moon will enter its next full phase the morning of Sunday, February 9. The snow moon will be at its fullest at 2:34 a.m. EST, but if you're not willing to stay up that late, it's still worth looking up. The previous evening—Saturday, February 8—the moon will be 99 percent illuminated on the East Coast. Check your local weather forecast and find a spot with clear skies to get the best view of the wintertime spectacle.

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