Event Date: December 5th
Time: ~7:00 AM
Brief
A couple of days ago, while I was busy mentioning the dim, most-outer planets transiting, much brighter Jupiter, Venus and Mercury (now -0.4) formed a slight arc-shape, with Venus a little more than over 7º separated from both. Now, Venus is "chasing" Mercury, yet will not catch it. Elusive Mercury reached greatest western elongation yesterday just after 4 PM local time at 20.4º in separation from the Sun, and will start to move faster than Venus in prograde motion next week. Here the two are now, with Mercury's orbit showing as well.
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As listed above, this is one of the more impressive apparent magnitude values for Mercury for this point in its cycle. The planet is not far from perihelion, yet far enough that while we approach perihelion next month, we are slightly closer to it than average for a greatest western elongation. It is also waxing while not shrinking quickly in angular size. Along with the Sun still rising several seconds later and Mercury still north of the Sun, it all combines towards the best morning apparition of the planet since very early in the year, when we saw it at greatest [western] elongation in January. Mercury rises 1 hour, 44 minutes before the Sun this morning, which is close to the largest rise gap while we see it here. As Mercury reaches superior conjunction, it will continue to brighten, reaching very impressive magnitudes during the last week that we see it easily.
This second image shows a zoom-in of Mercury, with a phase of 64%. The field of view is 1/10º, giving a magnification of about 500x. Realistically, with Mercury being low and out of atmospheric pollution, try to keep the magntidue closer to 200x.
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| click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp. |
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