By David Ward
As we climb towards the summer solstice, the days get longer and the nights get shorter, making stargazing more difficult. There is just not very much darkness this time of the year. There are a couple of interesting things up there to see, although the timing is not necessarily convenient. Two alignments in the celestial sphere above remind us that our place in the grand scheme of things is constantly shifting.
Let’s start with the planet Mercury, the first planet out from our sun. It never gets very far from the sun, making it difficult to spot. Right around May 17, it will be at its highest in the twilight evening sky. Astronomers call it Mercury’s greatest eastern elongation when it is as far from the sun as it gets in the western sky. Look for it in the west after sunset before it gets completely dark. You will have to be in a spot where you have an unobstructed view low into the west.
On May 28, a much brighter Venus will align with Mercury for a very close conjunction. The pair of the innermost planets will fit nicely into the field of view of a small telescope. Even though the two planets appear close to one another, they are actually about 100 million miles apart. They are simply lined up in our line of sight.
As summer progresses, Mercury will quickly drop out of sight, but Venus will slowly climb up and away from the sun making it more easily visible in our evening skies. If you miss this appearance of Mercury, astronomers call it an apparition, your next shot for an evening viewing will be in mid-September.
Just before sunrise on May 26, we will be treated to an early morning total eclipse of the moon when the sun, our earth and the moon will all line up, and the moon will pass through the shadow of the earth. It is only visible from the western states in this country so easterners will miss out. The last one that we saw was almost two-and-a-half years ago in January 2019.
Unfortunately this is an early morning, just before dawn occurrence. The moon first starts to slip into the Earth’s shadow at 2:45 a.m. It is totally immersed at 4:11 a.m. The moon will just graze through the edge of the earth’s shadow for only 14 minutes. Usually an eclipse of the moon lasts an hour or more.
Lots to see
The moon will appear brighter than during some eclipses but will still turn its characteristic reddish color, often called a “blood moon.” Atmospheric conditions here on earth will determine its exact color. The red comes from the combined sunsets and sunrises all around the globe refracting their light onto the darkened face of the moon.
Of course there is lots to look at up in the stars. Check out the Big Dipper riding high in the north, a sure sign of spring. Follow the curve of the dipper’s handle to the right to find Arcturus, a bright orange-colored star. It’s strange name actually means “guardian of the bears.” The two dippers are really two bears, Ursa Major and Ursa Minor, and Arcturus was thought by the ancient ones to have kept them in their orbits around the North Star.
If you stay up late after it gets completely dark, be sure to check out the Milky Way, a dimly glowing band of light stretching from north to south across the sky. In May it will be mostly in the east, while later in the summer it will be visible right overhead. See if you can find the Northern Cross embedded in the glow.
Ancient people were all over the place in their attempts to understand what the Milky Way actually could be. Their guesses ranged from a giant celestial river to the breast milk of a goddess. Today we know that it is the combined light of billions of stars in a giant galaxy, and we just happen to live in that galaxy. We honor the ancient Greek’s idea about the breast milk since we still call it the Milky Way.
