Event Date: January 31st
Time: 7:00 AM
Brief
Venus only rises 41 minutes before the Sun this morning, and that gap is shrinking fast now. Although Venus is moving a little faster north than the Sun, our star is still moving fast enough to stay ahead of Venus and therefore, the poor apparition of the planet as seen below. Also, as Venus approaches superior conjunction, it gets closer to disappearing out of our view. The Sun's glare will get in the way, and we will lose Venus from east visibility until about late-spring, in the evening sky. Taking a look at the image, as I included Venus' orbit showing that it is losing ecliptic latitude slowly.
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| click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp. |
Detailed
Back when we saw Venus at greatest elongation, it was close to its best apparition of the year in the eastern sky, and more than 30º above the horizon. The gap between rises for Venus and the Sun then was well over 3 hours, while as mentioned, the gap has shrunk substantially since. Even when we get Venus back in the evening sky, it will be a gradual emergence, and not seen for very long with the eye alone after Sunset for the first few months. The Sun of course gives off lots of glare, making it hard to see a planet even as bright as Venus. Until that time, try to still get a view of it as a tiny, 97% waxing gibbous only 10 arc-seconds in angular size. In comparison, when Venus is at inferior conjunction, thinking back to last June, it is about 6 times closer to us, at 1 arc-minute in angular size. When we have Venus at inferior conjunction when it is at aphelion and we are near perihelion (this time of year), Venus even is slightly larger in angular size. This time, at superior conjunction (March 28th 10:07 AM PDT), Venus will be about a month past aphelion as we start to move away from the Sun oursleves, on Earth. Therefore, its angular size will be a little smaller than it is now, although not optical-aid noticeable.
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