There are five fellow planets in our solar system that we can see with the naked eye, and in May we can see all of them except Mars.
The red planet is just coming out from behind the sun in our sky and is still lost in the glow of morning twilight. Next spring, though, Mars will definitely be out of hiding and put on a great show, as it’ll will be as close to Earth as it’s been in a couple of years.
This month in our Wichita Falls skies, the first planet to check out is Saturn, for a couple of reasons. First, it’s still nearly at its closest approach to Earth for 2013, about 825 million miles away. That’s a long way off, but that’s OK because Saturn’s a giant planet, second only to Jupiter in girth. Not only that, it has a fabulous ring system that spans well over 130,000 miles in diameter, making it a very enticing telescope target even if you have just a small scope.
Get out that scope out and check out Saturn, because if you do it right, you’ll love, love, love what you see. Make sure before you use it to let your scope and all the eyepieces sit outside for a good half-hour to acclimate to outside temperature. When you’re gazing at Saturn with your cooled-off scope, make sure to take long continuous views so you can get use to the light level coming into your scope. It does make a difference. You should be able to see the ring system and the actual planet with gap between the two. You may also see a few tiny starlike objects huddle close to Saturn. Those are some of its brighter moons.
Saturn is so easy to find right in the evening southeastern sky. As soon as it’s dark enough, look southeast for the brightest star you can see. That’ll be Arcturus. About halfway from Arcturus to the horizon will be two stars almost as bright as Arcturus arranged diagonally. The star on the upper right is Spica, and the “star” on the lower left is Saturn. This week you can also use the nearly full moon to find Saturn. On Tuesday night the moon will be just to the upper right of Spica, and Wednesday night the moon will be parked just to the lower right of the ringed wonder of our solar system.
Like all planets, Saturn slowly migrates around the sun in its orbit, and as it does it also journeys among the backdrop of stars in what’s called the zodiac band. All the planets in our solar system orbit the sun in more or less the same plane. That’s really apparent in the spectacle of the great planetary traffic jam this week and next in the low west-northwest sky. All winter long the bright planet Jupiter has been regaling us among the great winter constellations, but it’s about to slip off the celestial stage, not to be seen in our evening skies again until late next fall. Our Earth in its orbit around the sun is turning away from that part of space. It’ll be quite a send-off for Jupiter, though, as it’s temporarily joined by two other planets, Venus and Mercury in a very tight conjunction, or what I call a very close celestial hug that you don’t want to miss!
All this is going to take place in the very low west-northwest sky just a little bit above the horizon. You’ll need to have a really clear view in that direction with a little or no tree line. There’s also a narrow window time to see it.
Start looking for the three planets in lowest west-northwest about 45 minutes after sunset in the later stages of evening twilight. Don’t look too much later, because this planet trio will slip below the horizon by around 10 p.m. All three should be visible to the naked eye even if where you’re looking from has a lot of light pollution.
Early this week the three planets will be lined up diagonally. Venus will be the brightest one and the first one to pop out in the pink glow of twilight. Jupiter will be second-brightest just to the upper left of Venus, and Mercury will least brilliant just the lower right of Venus barely above the horizon.
Through the rest of this week, because of the combined effect of their orbits around the sun and our Earth’s orbit, the planets will be dancing among each other.
It’ll be fun to watch the alignment change from night to night, and it’s great to do with kids. By the end of this week they’ll be arranged in a nearly perfect little triangle. If you hold out your thumb at arm’s length, you should be pretty much able to cover up all three planets. You can’t do that very often!
Next week the triangular pattern will break up, but all three planets will still be a tight little group.
When you’re taking in this show remember that while these planets are really close together in the sky, they are nowhere near each other physically. They just happen to be nearly in the same line of sight from our Earthly perch. Mercury is the closest at about 106 million miles away from Earth. Venus is more than 150 million miles distant, and Jupiter’s the farthest at well over 560 million miles.
Jupiter’s also by far the biggest of the gang, at 88,000 miles in diameter. Venus is a little over 7,500 miles in girth, and Mercury’s just a little over 3,000 miles. I wouldn’t bother spending much time looking at these three with your telescope, because all three will really appear fuzzy as they’re so close to the horizon where you have to look through the maximum amount of Earth’s blurring atmosphere. Just enjoy the best planet show of 2013 with the naked eye. Don’t miss it!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/Paul and is author of the book “Stars, a Month by Month Tour of the Constellations,” published by Adventure Publications, available at bookstores at http://www.adventurepublica tions.net.planet jupiter, solar system, planets in our solar system <BR/>