During the evenings of July 9 through 11, watch how the faster-moving Mars closely interacts with the much slower Saturn. Despite the difference in brightness, they still should make for a rather eye-catching pair in the western twilight glow about an hour after sundown. On July 9, Mars is situated about one degree below Saturn. On the 10th, they are closest together, separated by 0.7 degree; Mars now appears just below and to the left of Saturn. On the 11th, Mars has moved noticeably farther away to Saturn's left.
On the universal date of Sunday, June 8, 2008 the Red Planet - Mars - and the Moon had made a splendid showing for all. For most of us, Mars and the earthshine Moon will only be separated by about a degree, but for lucky observers in New Zealand, this was an occultation event!
While the Phoenix mission is still making big news, use this opportunity to do some public astronomy outreach. Point the pair out in the sky to someone and tell what you know. Around 40 years has elapsed since humankind has first visited one - and then the other. How did our original expeditions to the Moon lead scientists to develop ever better instruments for remote study? How has our exploratory spacecraft evolved? If you think that's cool… Then stay tuned when the Moon, Saturn and Regulus team up in the night sky. To the unaided eye, the trio will make a lovely triangle with the Ringed Planet and the Little King situated to the north of Selene. Again, it's a great time to do some public outreach! Point a telescope Saturn's way. Titan - Saturn's largest moon - is visibly bright and can be seen in even small telescopes. Explain how our original fly-bys and landings on our own Moon led us on to explore a moon on a distant world! What did we find on Titan? How can it compare to what we discovered on the Moon and Mars?
Don't forget Regulus, either. The light you see from it on this night would have left roughly in 1931 - long before expeditions to the Moon, Saturn and Mars were even dreamed of. At about three and a half times more massive than our own Sol, Regulus is one hot customer when it comes to spin rate. Revolving completely on its axis in a little less than 16 hours, oblate Regulus would fly apart if it were moving any faster! Even though it's been around for a few million years, Regulus isn't alone, either. The "Little King" is a multiple star system composed of a hot, bright, bluish-white star with a pair of small, faint companions. Interestingly, when we combine the motions of Earth, Mars and Saturn, we find that the interval between conjunctions of Mars and Saturn average about every 2 years and 20 days. The last time Mars and Saturn got together was June 17, 2006. Their next meeting is set for July 30, 2010.
Even if you only use your eyes, the next few days are a great opportunity to share what you love and know with others… Enjoy!
Moon Occulting Mars Image - Credit: Ron Dantowitz, Clay Center Observatory at Dexter and Southfield Schools. Saturn and Titan - Credit: Casinni/NASA. Regulus vs. the Sun - Wenjin Huang, space.com/graphics
source: http://www.universetoday.com/
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