With everyone sticking closer to home these days, it’s a great time to spend an evening delving into a little astronomy. Air pollution has decreased and there is less air traffic, making it easier to see the moon, stars and planets.
The moon is waxing as June begins, going from just past first quarter (one quarter of the moon’s orbit). Waxing means the moon’s visible daylit area is getting bigger and will continue to do so until the moon is full on the evening of June 5, 2020. For the first week of June, you might use binoculars and the annotated map from this photo taken in January to identify some prominent features on the moon: The letters denote lava planes we call Mare (seas in English): A-Mare Crisium, B-Mare Fecunditatis, C-Mare Tranquilitatis and D-Mare Serenitatis, E-Sinus Iridum. The numbers denote craters: 1-Plato, 2-Copernicus, 3-Tycho and 4-Langrenus.
Stars in the Evening Sky
The Big Dipper will be nearly overhead in June. Look for the four stars forming the cup with three bright stars forming the handle. The Big Dipper is part of the large northern constellation Ursa Major, which represents the Bear.
Use the Big Dipper as a starting point to locate other bright stars and constellations of the northern night sky, and use the pictures and chart below to help orient yourself on clear nights in June and early July. The pictures help show the scale and orientation of the stars and constellations shown in the annotated star chart diagram.
Look southward from the cup of the Big Dipper for the constellation Leo the Lion, one of the 12 zodiac constellations. Look for the bright star Regulus which anchors the constellation at the front body of the Lion. Regulus is one of the bright stars used as guides and reference points to find your way around the sky. From Regulus, look above for the stars that form the outline of the Lion’s head or mane. The stars that form the head also form an asterism called the “Sickle” due to their shape. From the front of the Lion, look eastward for three stars in an extended triangular formation. There are two stars that form the hindquarters of the lion with the bright star Denebola further east marking the end of the lion’s tail. Leo is one of the easiest constellations to recognize and use as a guide to the night sky.
From Leo, move northward back to the Big Dipper and Ursa Major. Look carefully at the star that is located at the bend of the Big Dipper’s handle and is one star inward from the end. Those with good eyesight and in darker sky conditions may be able to see that the “star” is actually two bright stars close to each other which are the visual pair Mizar and Alcor.
If you can’t see the two stars with your naked eyes, don’t despair. They can easily be seen as two stars through binoculars. If you have or can borrow a pair, there is much in the sky that can be seen with common binoculars. Sit in a chair or lie down in your yard, on your deck or balcony, or any open space and sweep across the sky with your binoculars. You may be amazed at how many stars you can see. Look again at Mizar and Alcor. If the binoculars have enough magnification power, you may be able to see that Mizar is actually a double star, consisting of two stars next to each other.
Find the handle of the Big Dipper again. Using the handle as a pointer, look southward from the handle until you locate the bright star Arcturus located high overhead, as shown in the chart. Arcturus is the fourth brightest star in the entire night sky and is the brightest star in the summer sky at our northern latitudes. Arcturus is an orange giant star which is 37 light years distant from us. Can you see an orange or reddish tint for Arcturus with your eyes? If you have binoculars, the orange color is easily seen.
Arcturus anchors the southern end of the constellation Boötes, the Herdsman or the Plowman. Can you locate the other bright stars in Boötes using the chart? Can you locate and identify the other named stars in the constellations shown in the chart?
Planet Locations in June and July
From June through mid-July, the early evening sky will not be graced by bright planets. What planets are visible in a given month changes from year to year as planets move in their orbits and change their positions relative to earth.
In the late June pre-dawn sky you will find the planets Venus, Mars, Jupiter and Saturn. For Venus in mid to later June, look low to the southeast before sunrise while it is still dark. Venus and Jupiter will be bright and look like landing lights, and between them will be the visible planets Mars and Saturn in an extended line across the sky. The chart below shows the location of the planets and bright stars looking from east to the southwest at early pre-dawn in late June.
The planets Uranus and Neptune will also be above the horizon but are not visible to the naked eye. They require a telescope to see. The photo shows Jupiter and Saturn in the early morning hours looking southwest on June 3. Mercury will swing into the morning sky in later June, but Mars, Jupiter and Saturn will remain in the same section of the sky throughout the year.
If you stay up late, Jupiter and Saturn are rising in the southeast just before midnight at the start of June. By the end of June, the two planets will be rising before 10 p.m. as the Earth moves around the sun, getting closer to passing between Jupiter and Saturn and the sun. By mid-July, both Jupiter and Saturn will be prominent in the southeastern evening sky after dusk.
During normal times, we at the Analemma Society host Friday Night Public Sessions at Observatory Park at The Turner Farm as volunteers to the Fairfax County Park Authority. The Friday sessions are suspended due to the pandemic, but we expect to resume them when we can. Information about the observatory and programs can be found at www.analemma.org with updates periodically posted on our twitter account @AnalemmaSociety. Friday public sessions are free admission, and there is public parking.
Authors Jeff Kretsch and Alan Figgatt are with the Analemma Society.