Science

Look up Sunday night: Supermoon plus total lunar eclipse equals rare sky show

A total lunar eclipse will share the stage with a so-called supermoon Sunday night. That combo hasn't been seen since 1982 and won't happen again for a generation.

Bigger, brighter supermoon during total lunar eclipse won't happen again until 2033

Sunday's supermoon— when the new moon comes closest to Earth — will be coupled with a total lunar eclipse in a rare combination that won't happen again until 2033. (Jorge Duenes/Reuters)

Get ready for a rare double feature this weekend, starring our very own moon.

A total lunar eclipse will share the stage with a so-called supermoon Sunday night or early Monday, depending where you are. That combination hasn't been seen since 1982 and won't happen again until 2033.

When a full or new moon makes its closest approach to Earth, that's a supermoon. Although still about 354,000 kilometres away, this full moon will look bigger and brighter than usual. In fact, it will be the closest full moon of the year, about 48,000 km closer than the average distance. (The moon's orbit is far from a perfect circle.)

NASA planetary scientist Noah Petro is hoping the celestial event will ignite more interest in the moon. He is deputy project for the Lunar Reconnaissance Orbiter, or LRO, which has been studying the moon from lunar orbit since 2009.

"The moon's a dynamic place," Petro said Wednesday. "We're seeing changes on the surface of the moon from LRO. We're seeing that it's not this static dead body in the sky.... It's this great astronomical object that we have in our backyard, essentially. So people should get out and start looking at it."

Many stargazers, professional and amateur alike, dislike the term "supermoon," noting the visible difference between a moon and supermoon is slight to all but the most faithful observers.

"It's not like the difference between an ordinary man and Superman," said Alan MacRobert, a senior editor at Sky & Telescope magazine. "It really ought to be called a tiny, slightly little bit bigger moon, rather than the supermoon."

Last full lunar eclipse until 2018

The full eclipse of the moon will last more than an hour and be visible, weather permitting, from North and South America, Europe, Africa and western Asia. Exact viewing times in Canada vary depending on location. 

There are better times depending where you live to see the full eclipse. (CBC)

Eclipse viewing times

The following times are averages for the listed regions and will vary somewhat depending on exact location:

Halifax/East Coast: At 9:11 p.m. AT, the penumbral eclipse begins, when the Earth's partial shadow starts to touch the moon's face. At 10:07, the partial eclipse starts and the moon will begin to get red. Total eclipse starts at 11:11 p.m., peaks at 11:47 p.m. and ends at 12:23 a.m. AT. The whole show will be over at 2:22 a.m. Look for the moon between about 23 and 45 degrees up from the horizon.

Montreal/Toronto/Ottawa: Penumbral eclipse begins at 8:11 p.m. ET. At 9:07, the partial eclipse starts. Total eclipse starts at 10:11, peaks at 10:47 and ends at 11:23 p.m. ET. The whole show will be over at 1:22 a.m. The spectacle will begin fairly low on the horizon, at about 12 to 15 degrees depending on location, while during its peak the eclipse will be between 36 and 38 degrees degrees above the horizon.

Calgary/Edmonton: The sun won't set, and the moon won't rise, until after the eclipse has begun, so viewers in Alberta will miss the early part of the show. Moonrise is around 7:20 p.m. MT, when the moon will already be partially eclipsed. Total eclipse starts at 8:11, peaks at 8:47 and ends at 9:23 p.m. MT. The whole thing will be over by 11:22 p.m. Be sure to find a viewing spot with a clear sightline, because at its peak, the eclipse will appear only about 12 degrees above the southeastern horizon.   

Vancouver: The moon will rise at 6:57 p.m. PT with the full eclipse happening between 7:11 p.m. PT. and 8:23 p.m. PT. But not to worry, even though we miss the preliminary crossing of the moon into the Earth's shadow, the total eclipse can still be seen once our moon rises. This is when the moon will appear an orange, rust colour and where 'blood moon' gets its name.

There won't be another total lunar eclipse until 2018.

This weekend's eclipse marks the end of a tetrad, or series of four total lunar eclipses set six months apart. This series began in April 2014.

The 21st century will see eight of these tetrads, an uncommonly good run. From 1600 to 1900, there were none.

Observatories are marking the celestial event with public telescope viewing, although magnifying devices won't be necessary; the eclipse will be easily visible with the naked eye. Astronomers are urging stargazers to simply look to the east.

NASA will provide a live video feed of the entire eclipse — an option in case clouds obscure your own view.