May will be an interesting month to enjoy the night sky. The Big Dipper, a part of Ursa Major (the Great Bear), will be about as high overhead as it ever gets. If you extend the curve of the dipper’s handle, it will lead to Arcturus, the brightest star in the kite-shaped constellation Bootes (the Herdsman), then to the Spica, the brightest star in the hard to trace out constellation Virgo (the Maiden), and finally a short distance to the four stars of the small, squarish constellation Corvis (the Crow).

After enjoying this arc of bright stars, if you extend your gaze westward from Spica, you will be led to Regulus, the brightest star in the constellation Leo (the Lion), and then a similar distance to the bright twin stars of Gemini (the Twins). Castor is on the right (north) and slightly brighter Pollux is on left (south). If you have trouble remembering which is which, to the north of Castor is the bright star Capella (that also starts with a “C”) in the five-sided constellation Auriga (the Charioteer) and to the south of Pollux and nearer to the horizon is the bright star Procyon (that also starts with a “P”) in the tiny constellation Canis Minor (the Little Dog).

There will be two more even brighter lights in the evening sky during May. Very bright Jupiter will be close to the lower right of the twin stars and brilliant Venus will be closer to the horizon. The Moon will also enter the sky at midmonth. This will lead to one of the best sights in astronomy on the 18th when the Moon will pass very close by Venus. Whenever the Moon is paired with, or has a conjunction with, a celestial object during its monthly orbit, it is a special sight, but when it is very close to the most brilliant stellar object in the sky, it is truly one of the best sights in astronomy.

There will be one final special event on May 31, but while it is not one of the best sights in astronomy, it will surely be hyped in the media. It is the second full Moon of May, which is called a “Blue Moon.” It will not look blue unless a volcanic eruption or other event puts a lot of particles into the atmosphere that scatter much of the Moon’s light. No one knows why the second full Moon in a month or, according to earlier accounts, the third full Moon in a season is called a Blue Moon. One possible explanation that I like is that in olden days when monks used full moons to determine when religious festivals were held, the extra full Moon made this task difficult. This left the monks depressed or blue.

Highlights

-May 4: Antares, the brightest star in Scorpius (the Scorpion), will lead the Moon into the sky just after 11:00.

-May 5: The Eta Aquariid meteor shower will be seen during most of the night, but it should peak before dawn. Meteors will seem to have come from low in the eastern sky. You should see a meteor every few minutes.

-May 13: The crescent Moon will lead Saturn into the sky before dawn. It will follow Saturn on the 14th.

-May 16: Star Party sponsored by Grout Museum & Black Hawk Astronomy Club, Prairie Grove Park, Waterloo, 9-10:30.

-May 18: The crescent Moon will be especially close to brilliant Venus.

-May 20: The Moon will be to the left and in line with Pollux and then Castor, the bright twin stars of Gemini (the Twins), with much brighter Jupiter below.

-May 22: The Moon will be just ahead of Regulus, the bright heart of Leo (the Lion), as they cross the sky.

-May 26: The Moon will be to the right of Spica, the only bright star in the constellation Virgo (the Maiden). The Moon will be farther to the lower left of Spica on the 27th.

-May 30: The Moon will lead the bright star Antares in the constellation Scorpius (the Scorpion) into the sky just after 9:00. This will be the second time the Moon has visited Antares this month. Notice also that the Moon and Antares will rise about two hours earlier than they did on May 4.