Time: 8:15 PM
Brief
The Sun continues setting a little less than a minutes later each day this week. As we approach the summer solstice four weeks from now, the number of seconds between sets will continue do decrease. The Sun is about 20 minutes shy of its latest set time, happening in late June. Between now and then, we will lose Venus, as it reaches conjunction in early June. Here is the planet zoomed out, shown in orbit with the celestial guidelines and the waxing crescent Moon at about 3 days old.
Detailed
Its retrograde motion, coupled with twilight time lengthening by the week, will make Venus too hard to find very soon. It has waned to a 6% crescent and continues to catch up with us in orbit. Therefore, with a 53 arc-second diameter (26.2" radius), our formula for area gives us only 129 area arc-seconds to see, compared to a little over 300 back on April 30th when Venus reached greatest brilliancy. The result is a loss in apparent magnitude, although the glare of the Sun interferes with seeing Venus more than the lost area lit to our eyes.
As for the Moon mentioned for the image, I also included its orbit to show that despite being high in the sky at transit today, it will lose ecliptic latitude and declination this week, transiting a little lower each day. Look at the top left of the image to show how much it the orbit merges with the celestial equator, and refer back to my precession of the node entries for reminders on why I bring this up.
The second image jumps back to Venus. This will be the last week before [inferior] conjunction that I show Venus zoomed in, as it has waned considerably and getting close to the Sun. With the increase in angular size to almost 1 arc-minute, that is slightly larger than Jupiter at opposition. I will use magnification 200, to help see the lit portion a little better.
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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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