Welcome To The Family

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)

ATV passes:

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)