By David Ward
The main thing happening up there in the night sky in April is the planet Jupiter. Look for it high in the east just after it gets dark. Shining with a bright steady yellowish glow, it is unmistakable. The largest planet in our solar system is named for the Roman king of the gods.
If you have a small telescope, even a spotting scope, you will be able to see the four largest of Jupiter’s 67 moons. They are all the same brightness and stretched out in a straight line on either side of the planet. The moons change position from night to night and if you do not see all four, one may be behind or in front of Jupiter.
The famous astronomer Galileo Galilei first discovered those moons in the early 1600s using a telescope he made himself. He called them the Medicean stars in honor of his patron, Cosimo Medici. In those days if you wanted something, you had to scratch someone’s back. Sound familiar?
For many years they were know simply and boringly as 1, 2, 3 and 4. Now we know them by the names given them by Simon Marius, a contemporary of Galileo. He named them for the mythological characters Io, Callisto, Europa and Ganymede – four earthly lovers of Jupiter, king of the gods.
April is a great time to spot the elusive and seldom seen planet Mercury. Look for it on the evening of the April 8 just below and to the right of a thin crescent moon low in the west about 45 minutes after sunset. By mid-month, the innermost planet will be higher in the west and easier to spot. You will have to be able to see low into the west without hills or trees in the way.
Mercury in transit
Every now and then, Earth lines up perfectly with Mercury and the sun and we get to see tiny Mercury slowly crawl across the face of the sun. This event, known as a transit, will happen on May 9 for the first time in 10 years. If you want to observe this phenomenon, you will need a small telescope and filters designed for viewing the sun. Never look at the sun without eye protection either with the naked eye or through a telescope to avoid severe, permanent eye damage. The sun will rise that day with the transit already in progress, so you will need to be someplace with a clear eastern horizon. Go online to learn how you can safely view the sun.
Early risers are treated to a dramatic viewing of Mars and Saturn in the constellation of Scorpius, the scorpion. Look in the south before dawn for three bright objects making a triangle. The bottom one is the bright star Antares, the name of which means “rival of Mars” because of its reddish color. Up and to the right look for reddish Mars and up and to the left Saturn shines with a yellowish glow. Mars is getting brighter now as it is swinging close to us in its orbit.
In case you did not notice, a lot of deep space objects have been buzzing us lately. On March 11, a rock about 50 yards in diameter zoomed by us at 22,369 mph, close enough to take out a satellite or two. Nobody knew it was coming or even saw it until four days later. What would happen if something like that hit Twisp? Probably the Methow Valley News would not print our newspapers for a while. Then on March 21 and 22, two comets whizzed by closer than a comet has come in over 200 years. Astronomers were excited to get such a close view of them. I am just glad we dodged a bullet again!
Sometime in April, go out and take a last look at all those bright, beautiful stars of winter. Orion and his two hunting dogs, Taurus, the bull and the magical Pleiades star cluster are all drifting towards the west. By the end of the month, they will be fading into the sunset glare.