Penumbral lunar eclipse to move across the night sky

Skygazers will see the entire moon darken early Wednesday morning for a few hours, if the clouds break.

Skygazers will see the entire moon darken on Wednesday morning for a few hours, if the clouds break

H.R. MacMillan astronomer Derek Kief uses models to demonstrate how a penumbral lunar eclipse occurs. The moon is covered by the edge of the earth's shadow. (Rafferty Baker/CBC)

Early morning skygazers may get a look at a penumbral lunar eclipse on Wednesday, assuming the clouds aren't covering the sky.

This subtle eclipse occurs when the moon moves on the outer edge of Earth's shadow.

"The penumbral lunar eclipse is the lesser of the two [types of eclipse]," said H.R. MacMillan Space Centre astronomer Derek Kief.

"It's not going to be a total lunar eclipse. We have one of those coming on Jan. 31, 2018, where the actual full moon gets completely obscured by the earth's shadow

"You'll see a total dip, so the shadow will cross in front of the entirety of the moon, but it's just the penumbral — just the outermost layer, the lighter shadow."

In Vancouver, the best time to catch the penumbral lunar eclipse is between 4 a.m. and 5 a.m., according to Kief, but it begins around 2:30 a.m., and won't end until about 7 a.m.

H.R. MacMillan Space Centre astronomer Derek Kief looks at the half-metre cassegrain reflector telescope the centre uses to check out the night sky. (Rafferty Baker/CBC)

How to watch for it

"Naked eye works fine," said Kief. "It's always awesome to look at the moon through a telescope, just because you do get that cratering. You get to see the surface of the moon, which is gorgeous and really cool to see."

From Vancouver, the moon is always found toward the south, and you can begin looking for the eclipse in the southeast sky, then watch as it crosses over to the southwest.

Kief's tips for any photographers trying to capture the event include:

  • Use a tripod.
  • Try a long exposure, but not too long because the moon will move and create a "tail."  Kief suggests playing with 1-30 second exposures.
  • Use a remote, cable shutter, or timer to avoid shaking the camera.
  • Use a telephoto lens if possible.

Risk of clouds

There's a chance the astronomical event will be completely wasted on ground-dwelling Vancouverites if the clouds cover the sky.

"It's Vancouver so it's always a hit or miss," said Kief. "Hopefully the clouds will stay away for at least the morning hours."

CBC Meteorologist Johanna Wagstaffe is hoping the clouds don't ruin the experience for anyone who stays up late or wakes up early for the eclipse.

"Unfortunately an approaching Pacific rainmaker will bring increasing clouds through the overnight," she said. "But there is still a chance for a break in the clouds."

"Best chance is through the early morning, before the rain fills in around 6 a.m."

If you get any good photos of the penumbral lunar eclipse, let us know! Tweet them at @cbcnewsbc, or tag @CBCVancouver.


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