The newly-named dwarf planet Haumea and its two moons, Hi’iaka (bottom) and Namaka, were discovered by astronomer Mike Brown on December 28, 2004. He gave Haumea the nickname "Santa" at the time. Last week, it received its official name and classification as a dwarf planet. Illustration: NASA
Last week astronomers added another dwarf planet to our solar system. Named Haumea (how-MAY-eh), after the Hawaiian goddess of childbirth and fertility, it joins a select group that includes Ceres, Pluto, Makemake (mah-kee-MAH-kee) and Eris. Dwarf planets are large enough to be nearly spherical but not big enough to keep their orbital neighborhoods clear of other asteroids and the like. Haumea, discovered by Mike Brown (right), professor of planetary astronomy at the California Institute of Technology, stretches the definition of round. It’s shaped like an egg with dimensions of 1200 by 600 miles, and rotates once every four hours. Two tiny moons – Hi’iaka and Namaka – named after Haumea’s daughters, accompany the dwarf planet as it orbits the sun at the chilling distance of four billion miles. That’s a billion miles beyond Neptune, the furthest planet. If you could walk on Haumea, you’d feel the crunch of an unusual form of crystalline ice under your boots. An odd little world indeed.
Over a thousand minor solar system bodies, including four dwarf planets, have been discovered beyond Neptune. Here’s a sampling of the biggest ones. Notice that Eris is larger than Pluto. Illustration: NASA
Last night the sky was perfect for seeing the brilliant pass of the International Space Station after 8 o’clock. It was preceded by a fine pass of the ATV (Automated Transfer Vehicle) that serviced the station earlier this year.
In this 60-second time exposure photo, the International Space Station passes beneath the bright star Vega (upper right) last night, Sept. 22, about 8:20 p.m. Photo: Bob King / Duluth News Tribune
The following tables show the times of additional good passes this week of the ISS, the ATV and a rather peculiar satellite, the Early Ammonia Servicer (EAS) (below). The EAS is 1400-lb. unneeded piece of coolant equipment the size of a big refrigerator. It was jettisoned from the ISS last July and will burn up in Earth’s atmosphere sometime next spring. I’ve never seen this new satellite but according to the predictions, it will make some passes this week over our region. It’s not bright. Look for a moving light a little fainter than the stars in the Big Dipper at the appointed times. I wish you success!
Internation Space Station passes:
|Date||Time to look||ISS path in sky||Maximum altitude|
|Tuesday, Sept. 23||8:43 p.m.||from west to n.east||five fists (bright)|
|Weds., Sept. 24||7:34 p.m.||from wsw to east||overhead (brilliant!)|
|Weds., Sept. 24||9:10 p.m.||from wnw to north||three fists|
|Thurs., Sept. 25||8:01 p.m.||from west to n.east||four fists (bright)|
|Date||Time to look||ATV path in sky||Maximum altitude|
|Tuesday, Sept. 23||8:14 p.m.||from wsw to n.east||six fists (bright!)|
|Weds., Sept. 24||8:27 p.m.||from west to n.east||four fists (bright)|
|Thurs., Sept. 25||8:39 p.m.||wnw to north||three fists|
|Friday, Sept. 26||8:51 p.m.||northwest||three fists|
Early Ammonia Servicer (EAS) passes:
|Date||Time to look||EAS path in sky||Maximum altitude|
|Tuesday, Sept. 23||8:30 p.m.||n.west to n.east||three fists|
|Weds., Sept. 24||8:23 p.m.||n.west to n.east||four fists|
|Thurs., Sept. 25||8:15 p.m.||n.west to n.east||six fists (good pass!)|
|Friday, Sept. 26||8:07 p.m.||n.west to s.east||overhead (best!)|
|Saturday, Sept. 27||8 p.m.||n.west to s.east||six fists (very good)|