November 24, 2017

Astro-Challenge: See the Galilean Moons in 1,2,3,4 Order.

The Jovian System at 3AM EDT Friday. (Created by Author in Starry Night & Paint).

The Jovian System at 3AM EDT Friday. (Created by Author in Starry Night & Paint).

 

   Astronomy is chock full of alignments, synchronizations, and oddities that happen on variable cycles. This week, I’d like to point you towards one of those gee-whiz occurrences that happens early Friday morning. On May 28th, 2010, you’ll have the opportunity to view Jupiter’s classical four Galilean Moons in one-through-four order, all positioned on one side of the planet. This would also make for an interesting “family portrait” of the set. Jupiter is in dawn skies, currently rising about 4 hours prior to the Sun. The window of time is short; the moons are only in this arrangement from 06:33 UT until 07:50 UT, and “Jupiter-rise” for folks in the US Eastern time zone only occurs at about 0:700 UT (about 3 AM EDT local). Hence, only folks positioned in the Eastern and Atlantic time zones will have a shot at catching this alignment under dark skies. [Read more...]