Categories: Sky Reports
This week the moon passes Venus and then Mars, but it gets especially close to neither. On the evening of the 22nd it’s 5° to the lower right of Venus and both will fit within a pair of most binoculars. On the 23rd the moon is 6½° to the upper left of Venus and the two will fit within wide-angle low-power binoculars. That same night the star Pollux is only 2° from the moon and Castor is 6½° from the moon, so if you center low-power binoculars roughly mid-way between Venus and Castor you might take in at one glance the moon, Venus, Castor, and Pollux. Mars is just out of view to the upper left.
On the 24th the moon is 4½° above Mars, and the moon’s phase has changed noticeably from a thin to a thicker crescent.
Then on the 26th the 1st quarter moon is 4° from Regulus, in Leo.
This week watch Venus move diagonally upward and to the left against the background stars of Gemini, where its motion night-to-night is quite apparent. Try to estimate from your own observations when it will be in line with Pollux and Castor, as Mars was recently.
In the morning sky you’ll see additional planets. Jupiter and Mercury are too low to see well, rising in morning twilight, but Saturn is now far enough from the sun (90°) to pick it out a third of the way up the southeast sky in early twilight. Saturn is in the middle of Aquarius where there are no similarly bright stars to compete with it. Notice Saturn’s pale yellow light. Jupiter rises earlier and becomes easier to see morning-by-morning but Mercury does not rise high enough to see it well. The reason why Mercury is so hard to see in the morning sky in the spring, as in contrast to when it was recently in the evening sky, was explained in my Sky Report for April 10-16. Sky Reports are archived at https://stellarvistaobservatory.org/category/sky-reports/. And if you know someone who doesn’t currently see the Sky Reports but who would like to, send them this URL and they can bookmark it and read it weekly.
Early this week, before the moon becomes too bright, comes an opportunity to see a faint constellation that is also a star cluster. It’s Coma Berenices – “Bernice’s Hair” (Google can tell you how the name came about; it involves a Greek queen of Egypt) and it’s virtually overhead 2½ hours after sunset. To the eye it’s a patch of faint stars about 25° to the right of the bright star Arcturus (10° = the width of your fist held at arm’s length), and it’s visible to the eye under dark skies. With binoculars you’ll see a dozen or more stars spread over 6° of the sky that are the brightest members of a star cluster that lies almost 300 light years from earth. It has an estimated age of about 450 million years – 1/10th the age of our sun.
Stellar Vista Observatory provides portable telescopes and tripod mounted binocular kits on loan for free to residents and visitors in Kane County. Enhance your enjoyment of the night sky! To learn more, request a loan, or attend one of SVO’s free public star parties for 2023, visit https://stellarvistaobservatory.org/ or drop in to the Kane County Office of Tourism.