SKY GUIDE: This map represents the night sky as it appears over Maine during June. The stars are shown as they appear at 10:30 p.m. early in the month, at 9:30 p.m. at midmonth, and at 8:30 p.m. at month’s end. Venus and Mars are shown at their midmonth positions. To use the map, hold it vertically and turn it so that the direction you are facing is at the bottom. Sky Chart prepared by Seth Lockman

The month of June is named for the Roman goddess Juno, who is the wife of Jupiter. In Greek mythology she is named Hera. Its origin in Latin means “the younger ones.”

June always marks the beginning of summer for us in the northern hemisphere. This month that will happen at exactly 10:58 a.m. on Wednesday, June 21. That marks the longest day and shortest night for us and the highest point in our sky that the sun will reach for the whole year. Our days will reach 15 and half hours long at our latitude of 43.5 degrees, nearly halfway from the equator to the North Pole. If you fly just 1,600 miles north to the Arctic Circle, which is just north of the northern tip of Iceland, the sun would not set at all on this day.

The very short nights this month become even shorter when you add in the three levels of twilight – civil, nautical, and astronomical – which adds about another hour and a half on each side, so you are down to just five and a half hours of true darkness around the summer solstice. The beginning of astronomical twilight is defined as the sun being 18 degrees below the horizon.

There will still be several interesting highlights to look for this month regardless of the extremely short nights. These include brilliant Venus at its very highest and best for the year, both of our neighboring planets, Mars and Venus buzzing through the Beehive star cluster just 11 days apart, Venus closing in on Mars all month long but never quite catching it, Saturn becoming a late evening planet again toward the end of June, the asteroid Parthenope at opposition, another Comet LINEAR visible in a telescope in Aquila, and the waxing crescent moon passing near Venus on the summer solstice.

Our sister planet, Venus, is catching up with the slower moving Earth this month and will reach its greatest eastern elongation from the sun on June 4. This is when it is exactly half lit by the sun. It will be 45 degrees from the sun that day and not set until more than three hours after sunset, which is the latest it can ever set. After that it continues to get brighter and closer to us even as it is getting more crescent and less illuminated by the sun. Venus lines up with Castor and Pollux in Gemini on June 1. Then it crosses into Cancer the Crab two days later and then it will follow Mars right through the Beehive open star cluster on June 12 and 13.

Then keep watching Venus as a slender waxing crescent moon passes within 3 degrees of the planet on the summer solstice. Mars will be just 4.5 degrees further east in Leo and the Beehive cluster that both planets just passed through a few days earlier will be 7 degrees to the west.

Mars passes through the Beehive cluster first, on the first and second days of this month, and then Venus follows it along the same ecliptic path 11 days later, on June 12 and 13. Mars is still getting a little fainter each day as it falls farther behind Earth in its orbit. Look at the red planet with binoculars and you will see a brilliant ruby embedded in a sea of 100 or so fainter diamonds. Two exoplanets were discovered in this star cluster back in 2012 using the radial velocity method. You can think of them as two bees in the beehive. The Beehive open star cluster in Cancer, a huge swarm of stars, also known as M44 or Praesepe, which means manger or crib in Latin, consists of about 1,000 stars located about 600 light years away from Earth. That means that the light you are seeing from the Beehive left there just before the Renaissance started and the printing press was invented in 1450.

The Hyades open star cluster nearby in Taurus is related to the Beehive since they both have a common origin. The stars in both clusters are about the same age, 600 million years old, and they have similar motions through space. The Hyades are receding away from us at 43 km/second. The Hyades, which mark the V-shaped face of Taurus the bull, is the closest star cluster at only 150 light years away. It contains about 500 stars, similar to the Pleiades, which are about 400 light years away, but it is not related to them. The name Pleiades comes from the Greek, plein, which means to sail. So picture these 500 young stars sailing through space not far from us, their light leaving its source just as Galileo turned the first telescope to the heavens to begin the scientific age of discovery and the search for our true origins. His legacy has now been greatly extended through the remarkable discoveries of the James Webb Space Telescope.

Saturn begins the month rising at 1:30 am. in Aquarius and it will rise well before midnight by the end of the month. The ringed planet will reach opposition in two months when it will be at its closest and best and brightest and rise at sunset. Jupiter is now in Aries the Ram and is about two and a half hours behind Saturn. The King of the planets will rise at 4 a.m. starting this month and at 2 a.m. by the end of the month.

Another Comet LINEAR discovered by the Lincoln Near-Earth Asteroid Research telescope in 2002 will be visible in a telescope this month in Aquila, which is part of the summer triangle. It will only reach 11th or 12th magnitude. It will be just below the Cepheid Variable star Eta Aquilae, or Bezek, which means “to scatter” in Arabic. This star varies from its brightest of 3.5 magnitude to its faintest of 4.3 every 7.17 days and is located about 1000 light years away. Another Cepheid variable star, Delta Cephei, varies between about the same brightness’s every 5.37 days. Henrietta Swan Leavitt discovered this period-luminosity relationship of all Cepheid Variable stars back in 1908. They have periods of between 1 and 100 days. The longer the period, the brighter the star. There are about 1000 known Cepheid variable stars in our galaxy of 300 billion stars, so they are quite rare. Even Polaris, our current North Star is a Cepheid variable, but it does not change enough in brightness to notice without a good telescope.

JUNE HIGHLIGHTS

June 3: Full moon is at 11:42 p.m. … The largest telescope in the world at the time, the 200-inch Mt. Palomar telescope, was dedicated on this day in 1948. George Ellery Hale designed it.

June 4: Venus is at greatest eastern elongation from the sun. The Compton Gamma Ray observatory was allowed to re-enter our atmosphere in 2000, ending its very successful 10-year mission.

June 5: In 1989 Voyager 2 made its closest approach to Neptune on its way out of the solar system.

June 9: The moon passes 3 degrees south of Saturn.

June 10: Last quarter moon is at 3:31 p.m.

June 13: In 1983 Pioneer 10 left the solar system. The Japanese Hayabusa spacecraft, which means “peregrine falcon,” returned the first ever samples of an asteroid to Earth on this day in 2010. They were from an asteroid named Itokawa.

June 14: The moon passes 1.5 degrees north of Jupiter this morning.

June 16: In 1963 Valentina Tereshkova became the first woman in space and still has the only solo spaceflight by a woman.

June 18: New moon is at 12:37 a.m. Saturn is stationary ending its normal prograde motion and beginning its westward retrograde motion in Aquarius today.

June 21: The summer solstice is at 10:58 a.m. The moon passes 4 degrees north of Venus tonight.

June 22: The moon passes 4 degrees north of Mars tonight.

June 26: First quarter moon is at 3:50 a.m.

June 29: George Ellery Hale was born in 1868.

Bernie Reim of Wells is co-director of the Astronomical Society of Northern New England.