By Mike Lynch
The king of the planets will get your attention in the eastern sky this month and will continue to dominate the Northwest sky well into spring.
It reaches its closest approach to Earth this weekend, something astronomers call opposition. Right now the largest planet of our solar system is about 391 million miles away, the closest it’ll be to our world this year. That’s close for Jupiter.
It’s by far the largest planet in our solar system with an equatorial diameter of 88,000 miles, dwarfing our 8,000-mile-wide Earth.
Jupiter resides in the constellation Gemini the Twins, parked just to the right of Gemini’s brightest stars, Castor and Pollux.
Jupiter’s available in our heavens all night long as it take a very high arc across the sky through the night. Just like a full moon, which we will have later this month, Jupiter rises at sunset and sets at sunrise.
Jupiter is basically a huge ball of hydrogen and helium gas, much like our sun. When you get Jupiter in the eyepiece of your telescope you’ll see at least some of its horizontal parallel cloud bands on the disk of the gargantuan planet.
Even the smallest of scopes with decent focus can usually pick up two of the dark cloud bands running on either side of Jupiter’s equator. You may see a lot more this month and perhaps some faint color to the bands.
The clouds on Jupiter are mostly made up of ammonia and methane compounds. They swirl around Jupiter at speeds about 400 miles an hour, and contain eddies and storms within them.
The biggest of Jupiter’s storms is the famous Red Spot. Other smaller red spots have also been seen on the great planet.
Jupiter’s atmosphere is so active because of its immense mass and its resultant huge gravitational force.
There’s also lots of lightning on Jupiter. Because of the huge magnetic field generated by its rapid rotation, aurora are common around Jupiter’s pole.
When you’re viewing Jupiter, or anything else in your telescope, just remember that higher is better. The higher in the heavens Jupiter is the better the chance you’ll have to get a really clear look at it.
Also start with a lower magnification eyepiece and work your way up to a higher magnification. You will reach a point of limiting higher magnification where the image will get too muddy. Then bump down to a lower magnification.
Remember also that not all nights are the same for telescope viewing. Even if the skies are clear, high winds in the upper and lower atmosphere can diminish what you see and how much magnification you can obtain clearly.
If Jupiter doesn’t come in too clear one night, try it again the next night.
Always look through your telescope at any object for an extended time, at least 10 minutes. That will give you more time to get used to the different light level and will allow you to see more detail.
Another attraction around Jupiter are its four largest moons that look like little stars in a line on either side of the planet, depending on where they are in their individual orbits. Even the tiniest of scopes and binoculars can pick them up.
You may even see a tiny little tail attached to Jupiter. That’s actually Jupiter’s moons.
Mike Lynch is an astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and is author of “Stars, a Month by Month Tour of the Constellations.” Check his website, www.lynchandthestars.com.
The Everett Astronomical Society: www.everettastro.org.