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A preview of the coming northern lights season*
Here’s a link to the mlive.com web site for an article on how great northern Michigan is to view the Northern Lights or Aurora Borealis. Here’s the link to Best northern lights viewing in Michigan by Kim Schneider.
An auroral display. Credit Bob Moler.
* The “aurora season” or “northern lights season” coincides with the coming solar or sunspot peak which is expected to occur in 2013, and last several years.
Tip o’the dew cap to Pat Stinson.
03/08/11 – Ephemeris – The lunar sea of Crises
Fat Tuesday, March 8th. The sun will rise at 7:08. It’ll be up for 11 hours and 31 minutes, setting at 6:39. The moon, half way from new to first quarter, will set at 10:51 this evening.
The one feature that is prominent on the crescent moon tonight will be the dark sea Mare Crisium or sea of Crises. It appears easily in binoculars. It, as all the lunar seas, are really a large crater that was created about 3.85 billion years ago by an asteroid strike. It appears foreshortened because it’s near the moon’s limb. If you watched the proximity of Mare Crisium to the edge of the moon over time, you’d notice that sometimes it’s closer to the edge than at other times. The moon has a constant rotation, but its orbit isn’t circular, so the moon appears to rock back and forth slowly, and nods a bit too. The effect is called libration, and allows us to see 60% of the moon from earth.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Blog Addendum:
Below is an image from Virtual Moon Atlas pointing out Mare Crisium, the Sea of Crises. VMA is a free program. See the links for free programs on this blog.
Mare Crisium via Virtual Moon Atlas
Bob Moler's Ephemeris Blog 