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Driftless Dark Skies: Jupiter

March 4, 2016 by John Heasley

 Jupiter is at opposition on March 8 when it’s at its closest to Earth.  It will rise in the east at sunset, pass high overhead in the south at midnight, and set in the west at sunrise.  Jupiter blazes brighter than any star (twice the brilliance of Sirius) which makes it very easy to spot in the night sky. 

hotspot_cover_1280With a small telescope or binoculars on a tripod, you can make out some of the darker cloud belts in Jupiter’s atmosphere and maybe even the Great Red Spot.  You should also be able to spot small “stars” off to the side of Jupiter.  These are the four largest of Jupiter’s 67 moons: Io, Europa, Ganymede, and Callisto.  Ganymede is the largest moon in our solar system, even bigger than the planet Mercury.  Europa is especially intriguing since its one of the leading candidates for finding life beyond Earth.  It may have all three of the necessary requirements for life: liquid water, energy source, and organic compounds.  We might know better by the 2020s when NASA has plans to send a robot to orbit and land on Europa. 

Galileo was the first to turn a telescope to Jupiter.  He was astounded by what he saw.  In just one week in January 1610, he saw four “stars” in a line by Jupiter appearing and disappearing as they changed position.  The astronomical writings of Copernicus, Kepler, and Newton are important works, but I don’t usually recommend them for recreational reading.  Galileo’s Starry Messenger (Siderius Nuncius) is an exciting story to read.  Galileo tells how his “confusion was transformed to amazement” as he figured out what he was seeing: “Now we have not just once planet rotating around another while both run through a great orbit around our Sun; our own eyes show us the four stars which wander around Jupiter as does the Moon around the Earth, while all together trace out a grand revolution about the Sun in the space of twelve years.” 

Jupiter has been visited by robot explorers such as Pioneer, Voyager, Ulysses, Galileo, Cassini, and New Horizons.  Juno is on its way and will arrive at Jupiter on July 4 this summer.  But you can visit Jupiter any spring night in the Driftless Area and see it with your own eyes as Galileo did.  Kickapoo Valley Reserve astronomy educators will have a telescope set up on March 18 as part of the Equinox Stargaze.  Look for Jupiter just above the waxing gibbous Moon on March 21.  On the evenings of March 7 and 14, you can watch the shadows of Europa and Io crossing the cloud tops of Jupiter.  It gives us a chance to imagine the volcanoes erupting on Io and to ponder the strange creatures that might be dwelling in the seas of Europa. 

John Heasley is an astronomy educator and stargazer who enjoys connecting people with the cosmos. He volunteers with NASA/JPL as a Solar System Ambassador. For more information about stargazing in southwest WI, like Driftless Stargazing LLC on Facebook and find out whenever there’s something awesome happening in the skies. Driftless Dark Skies appears monthly in the Voice of the River Valley.

Driftless Dark Skies: Five Worlds at Once

December 31, 2015 by John Heasley

As the New Year begins, we will be able to see all five classical planets at the same time.  The last time we were able to see Mercury, Venus, Mars, Jupiter, and Saturn all at once was eleven years ago when they were also visible in the sky before sunrise. 

moon venus ls 2

Crescent Moon and Venus at dawn above the Driftless Area in early December. Photo by Lynda Schweikert.

For the Driftless Area, around 6 am is a good time to have a look for the planets.  Three things will help you tell planets from stars.  Planets follow the same path as the sun across the southern sky.  Planets twinkle much less than stars. Planets are brighter than most stars.  You can see them with just your eyes and won’t need a telescope or binoculars. 

Our moon makes an excellent guide.  On December 31, the waning gibbous moon is just below Jupiter in the southwest.  Each night, the moon shrinks a bit more and is found further to the east.  The last quarter moon is between Jupiter and Mars on January 1 and 2.  Look for the waning crescent moon just above and to the right of Mars in the south on January 3.  The moon continues to wane and is found between Mars and Venus on January 4 and 5.  On January 6, you’ll see a slim crescent moon just above Venus and Saturn in the southeast.  Venus is the brightest object in the sky after the moon, while Saturn is dimmer and a little below and to the left of Venus.  There’s another chance to see the moon, Venus, and Saturn together on January 7.  Continue to watch as Venus and Saturn move closer together.  They’re at their closest on January 9.  After that, Saturn will be above and to the right of Venus and moving closer to Mars.  Mercury joins the other four planets around January 20.  Look for it below and to the left of Venus in the dawn sky.  Mercury continues to get closer to Venus as January ends and should be visible until February 20. 

You can enjoy an encore when the moon passes near Jupiter on January 27 and 28, Mars on January 31 and February 1, Saturn on February 3 and 4, Venus on February 5, and Mercury on February 6. 

There’s also a chance to see a comet in the dawn skies of January.  Comets are traditionally unpredictable, so it’s hard to say how bright Comet Catalina will be.  But look for it near Arcturus on December 31.  Arcturus is the bright orange star high in the southeast.  By mid-January, Comet Catalina will be near the handle of the Big Dipper.  Hope you enjoy the mix of the predictable and unpredictable as we being a new year. 

You can enjoy some moongazing at the Kickapoo Valley Reserve on January 23, 6-8 pm.  Enjoy the full moon while skiing, snowshoeing, or walking. KVR astronomy educators will have binoculars and telescopes set up along Old Highway 131 Trail for you to stop and enjoy the highlands, maria, craters, and rays of the Wolf Moon. Event is free and open to the public.  Annual or day trail pass required.

John Heasley is an astronomy educator and stargazer who enjoys connecting people with the cosmos. He volunteers with NASA/JPL as a Solar System Ambassador. For more information about stargazing in southwest WI, like Driftless Stargazing LLC on Facebook and find out whenever there’s something awesome happening in the skies. Driftless Dark Skies appears monthly in the Voice of the River Valley

Driftless Dark Skies: Planets at Dawn

October 1, 2015 by John Heasley

Early risers in the Driftless Area will be able to see three worlds slowly shifting in the eastern sky before dawn this month: Venus, Mars, and Jupiter.  Look for them an hour or so before sunrise, which is 7:00 at the start of the month and 7:35 at the end of the month.

Venus is the easiest to find.  On October 1, it rises 2 ½ hours before the sun and is the brightest light in the sky.  Look for it high in the east.  Jupiter is the second-brightest object and is 17 degrees below and a little to the left of Venus.  That’s about the distance between your pointer and pinkie when held at arm’s length.  Mars is much dimmer and ruddier and halfway between the two.  There’s a bright star halfway between Mars and Venus.  That’s Regulus.  It’s a nice reference point as you watch the wanderings of the three planets.

Venus, Moon at dawn; photo by Jean Napp, Starsplitters of Wyalusing

Venus, Moon at dawn; photo by Jean Napp, Starsplitters of Wyalusing

A week later, the waning crescent moon joins the show.  Look for it just above Venus on October 8, just to the right of Jupiter and Mars on October 9, and below Jupiter on October 10.  If you want a challenge, you may be able to see a fourth planet, Mercury, on October 11 when it is just above the moon.  You’ll need a clear horizon to the east and maybe binoculars to see the innermost planet.  Best time to look is between 6 and 6:30.  Look for Earthshine on the dark side of the moon.  That’s sunlight being reflected by day side of Earth onto the night side of the moon.

The planets get even closer together in the second half of October.  On October 17, Mars and Jupiter pass by one another less than half a degree apart.  That’s the width of a full moon.  You could cover both with just your little finger.  Venus and Jupiter are closest together on October 25 and 26 when they are just one degree apart.  On October 27 and 28, all three planets are grouped within five degrees and can be enjoyed all at once in your binoculars.  On November 2 and 3, Venus and Mars will be less than one degree apart.

If you are not an early riser, don’t feel left out.  You can see Saturn in the southwestern sky after sunset.  October 15 and 16 are good dates when the moon is just to the right and then the left of Saturn.  You can have a look at Saturn through a telescope at the Kickapoo Valley Reserve Dam Challenge Stargaze on Friday, October 2nd 7-9 pm.  Be sure to enjoy the Friends of KVR Pasta Dinner from 5-8 pm.

In only five weeks this fall, you will have seen these three worlds dance in the dawn shifting position from Venus/Mars/Jupiter to Jupiter/Mars/Venus and maybe even caught a glimpse of a  fourth world, Mercury, all while enjoying the autumnal world of our Driftless Area.

John Heasley is an astronomy educator and stargazer who enjoys connecting people with the cosmos. He volunteers with NASA/JPL as a Solar System Ambassador. For more information about stargazing in southwest WI, like Driftless Stargazing LLC on Facebook and find out whenever there’s something awesome happening in the skies.  Driftless Dark Skies appears monthly in the Voice of the River Valley.

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