Credit: Bob King

Why Isn’t The Earliest Sunset On The Shortest Day?

The dark days are upon us. Welcome to the earliest sunsets of the year this week and early next. Counter to intuition, the sun sets earliest before the winter solstice, not on it. Shouldn’t the sun set earliest and rise latest on the shortest day of the year? Well no, and it’s because our clocks keep steady, uniform time…
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Johannes Hevelius from his 1687 Firmamentum Sobiescianum sive Uranographia atlas.

Discover The Funny Side Of Delphinus

With the moon nearing first quarter or ‘half-a-pie’ phase, the sky is still dark enough to go out and look for constellations. Some observers even prefer a little moonlight because it snuffs out the fainter stars that might otherwise add confusion. This week we’ll make one final swim with the sky’s dolphin, a slippery fellow near…
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Black Hole Spins And Eats A Cosmic Christmas Wreath

My neighbor stopped by the other night with the Christmas wreath we’d ordered. First, I stuck my nose in it to breathe in the citrusy tang of balsam fir needles. Delicious! The next day I hung it outside the door and admired the green whirls and big red ribbon. A cheerful sight on grayovercastday #14 here…
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Using Minneapolis as an example, there will be a brilliant pass of the ISS Sat. Dec. 3 starting about 6:18 p.m. local time. At just past 6:21 p.m., the station will fade out nearly overhead in the W of Cassiopeia when it enters Earth's shadow. Credit: Heavens Above/Chris Peat with additions by the author

Is That The Space Station Overhead? Heck Yeah!

December brings an entire month of evening space station passes for many locations in the northern hemisphere.  And because night comes quickly in this solstice month, lots of us will have the opportunity to spot it. You can always tell the International Space Station (ISS) apart from every other satellite by its sheer brilliance. When orbiting…
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ESA/Roscosmos/ExoMars/CaSSIS/UniBE; mosaicking tool: AutoStitch (University of British Columbia).

Fly Over Martian Chasms And Craters With ExoMars

Fly over Mars along with the joint Russian-European ExoMars orbiter. While the Schiaparelli lander crashed landed on Mars on Oct. 19 due to faulty commands from its computer, we all felt disappointment. But the other half of the ExoMars Mission is performing splendidly. The Trace Gas Orbiter (TGO) arrived at Mars on Oct. 19 and currently…
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