Saturday, October 25, 2014
Inquirer Daily News

Super Moon(s) and Space Launch

Heads-up: Supersize moon coming Saturday night, a space launch Sunday afternoon.

Super Moon(s) and Space Launch

A "super moon" rises above a egret nesting area on the west side of Wichita, Kan., in 2012. A supermoon, is the coincidence of a full moon (or a new moon) with the closest approach the Moon makes to the Earth on its elliptical orbit, or perigee.
A "super moon" rises above a egret nesting area on the west side of Wichita, Kan., in 2012. A supermoon, is the coincidence of a full moon (or a new moon) with the closest approach the Moon makes to the Earth on its elliptical orbit, or perigee. AP Photo/The Wichita Eagle, Bo Rader, file

When the moon rises right after sunset Saturday, it will look as though it put on some weight, even though technically it is weightless.

The so-called perigee moon will appear an estimated 14 percent larger than usual, and roughly 30 percent brighter once it gets cooking.

That’s because it will be closer to the Earth than usual. The moon’s orbit is elliptical, somewhat like the Earth’s around the sun.

At perigee, by NASA’s calculation, it is about 30,000 miles closer to the Earth than it is at apogee, its farthest distance -  252,000 miles.

By fortunate coincidence, we will be treated to perigee moons again on Aug. 10 and yet again on Sept. 9. NASA says the Aug. 10 moon might be of special note because it reaches perigee at the same hour that it becomes “full.”

We can’t speak on what viewing conditions will be like on those August and September nights, but Saturday night they should be fabulous, clear, and without much view-obscuring water vapor in the air.

Incidentally, according to NASA, supermoons aren’t all that unusual, occurring about once every  13 ½ months. As for having three in a row, this will be first time since … last year.

For your daytime viewing on Sunday, a NASA rocket launch from Wallops Island, Va., should be visible here if conditions are right.

The Antares ORB2 will be on a mission to resupply the International Space Station. Launch time is 12:52 p.m. Sunday. According to NASA it should be visible here in the southeast sky 2 minutes after launch. See map for other information.


Tony Wood Inquirer Weather Columnist
About this blog

Everyone talks about the weather, and here we write about it.

When we’re around and conditions warrant, we’ll keep you updated about what’s coming, but we will do our best always to discuss weather and climate developments in context and remind you that nothing in the atmosphere happens in a vacuum.

Tony Wood has been writing about the atmosphere for The Inquirer for 26 years.

Reach Tony at twood@phillynews.com.

Tony Wood Inquirer Weather Columnist
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