Champaign-Urbana Astronomical Society
Looking Up
June 2021
Did you see Mercury last month? I believe we had a clear night on May 13 and the Moon was beautiful to the left of Mercury. I hope you saw that. Mercury is no longer in the picture (well, not like it was in May) and, in fact, it will pass between the Sun and the Earth on June 10 to slip into the morning sky. Mercury will ascend in the morning sky though it’ll reach its greatest separation from the Sun early next month. Early risers may see it at the end of June but don’t mistake it for the star Aldebaran – they’ll be relative close in separation and brightness.
Back to the evening sky. Venus is still in the process of making a slow ascent from the horizon. At the beginning of June, it sets at 9:45pm CDT, a bit over an hour past sunset. That stretches to about 95 minutes at the end of June. Venus comes pretty close to passing over the rich star cluster, M35, in the foot of Gemini, but the sky will be too bright to see the cluster. Look for Venus low in the west-northwest. At magnitude -3.8, you don’t have to wait that long after sunset to start looking. A thin crescent Moon is just below and right of Venus on the evening of the 11th (pictured here) then midway between Venus and Mars on the 12th. Note this month how the separation between Venus and Mars is decreasing. By the end of June, it’s about 7.5 degrees. On the evening of the 24th Venus is in line with the stars Castor and Pollux.
Mars is pretty faint (well, for Mars, anyway) at magnitude +1.8, but Mars does something cool this month. Easily locate Mars on June 13 since the crescent Moon will be right above it. Then keep an eye on the planet with binoculars. On June 23 Mars will cross in front of the Beehive Cluster in Cancer. Granted it’s not high in the sky but if you can find a good, unobstructed horizon, you got a good shot. Mars will look like an extra “star” in the cluster but, of course, the cluster is well over 15 millions times further away!!
Jupiter and Saturn are still in the morning sky but, in mid-June, they’re both above the east-southeastern horizon by just after midnight. By sunrise, they are closed to being on the meridian. On June 1, a roughly 3rd quarter Moon is just below Jupiter but the scene repeats itself near the end of the month. The Moon is near Saturn on the morning of the 27th and then below and between the two planets the next morning.
Besides Mars in the Beehive, diligent observers might look for the brightest asteroid, Vesta, among the stars of Leo. It’ll be about magnitude +7.6 so you’ll need binoculars at minimum. It’s nice when asteroids are near stars. Start with Theta Leonis (one of the Lion’s back legs) and go past the galaxies M65 and M66 to the star 78 Leonis (magnitude 4). See the next page for a chart. Vesta is between two stars at magnitudes 5.8 and 6.5. Now the key to finding an asteroid is to watch over a couple of nights and look for movement. There’s a reason why the name “asteroid” means “starlike!”
We also have an annular eclipse coming up on June 10, though the path of the Moon’s shadow goes over both the Earth’s geographic and magnetic poles. Eastern Canada has probably the best view for a inhabited area. Will we get to see it here? Maximum eclipse occurs while it’s still dark here. You may get
to see some or the Moon exiting the Sun disk right at sunrise on the 10th. Now if you try, USE ECLIPSE GLASSES! DO NOT look at the Sun with just your eyes! The entire eclipse is over around 8am.
Oh, yeah, and happy summer, too! The summer solstice occurs on Sunday, June 20, at 10:32pm. That is when the Sun is over the Tropic of Cancer. We’ll have our longest day and the Sun will be at its highest at noon (though not straight up). I got into a bit of a “heated discussion” with a couple of meteorologists who claim summer begins June 1 and they “have the data to prove it.” I haven’t seen the data yet. The calendar is so arbitrary. Whether you like the solstice or not, it’s a definitive date and time! I suppose in the long run it really doesn’t matter, right?
-DCL
