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Moon and Jupiter late night to dawn

Tonight – December 30, 2015 – if you stay up until very late evening, you just might catch the waning the moon and the giant planet Jupiter coming up over your eastern horizon. But if you’re not one to stay up late, wake up before sunrise on December 31 to catch the moon and Jupiter much higher up in the sky as seen from the entire Earth. Also in this post … a preview of the planet Mars in the months ahead. Follow the links below to learn more.

Jupiter and the moon on December 30

Mars-watch alert in 2016!

The little white dot near the moon here is Jupiter.  Photo by Masaaki Shibuya.

The little white dot near the moon here is Jupiter. Photo by Masaaki Shibuya.

Jupiter and the moon on December 30. Once the moon and Jupiter rise on the night of December 30, they’ll go westward across the sky, much as the sun does during the day. Click here for recommended almanacs that can help you find when the moon and Jupiter rise into your sky.

We’re now approaching the best time of year to see Jupiter. That always happens for some weeks around the time Earth passes between the sun and this giant planet. In 2016, that event occurs on March 8. Astronomers call it an opposition of Jupiter, because then Jupiter will appear opposite the sun in our sky, rising in the east as the sun sets in the west.

Between now and March 8, watch for Jupiter a little earlier each evening!

Have a telescope or even a good pair of binoculars? Once Jupiter climbs above the murk and haze of you horizon, you might want to take a look at Jupiter’s four major moons: Io, Europa, Ganymede and Callisto. This handy sky chart on Jupiter’s moons will let you know which moon is which.

Also, know that Jupiter isn’t the only planet in the morning sky. In fact, three other planets are also there, gearing up to be joined by Mercury. When Mercury joins the other planets before dawn, we’ll be able to see five planets in the sky simultaneously. That’ll happen between about January 20 and February 20, 2016. It hasn’t happened since 2005, so mark your calendar!

The planets have been for early birds over the past months, and they still are. Besides Jupiter, catch Venus, Saturn and Mars in the predawn sky now. See the sky chart below.

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Are you a morning person? Then look for the four morning planets. Venus and Saturn appear low in the southeast, not far from the sunrise point on the horizon. Mars is to the south at this early morning hour whereas brilliant Jupiter shines to the right of Mars and Spica, outside the sky chart. The green line depicts the ecliptic - Earth's orbital plane projected outward onto the great dome of sky.

There are four planets in the morning sky now. Venus and Saturn aren’t far from the sunrise point on the horizon. Mars is to the south before dawn (or north if you’re in the Southern Hemisphere). Brilliant Jupiter shines near Mars and Spica, outside this chart. Soon, Mercury will come back to the predawn sky, and then 5 planets will be visible simultaneously.

Mars-watch alert in 2016! Mars is another planet to watch in the coming year, and especially in the coming months! Earth will pass between Mars and the sun this May. That’s something we do only once about every two years. So Mars’ appearance in our sky alternates from year to year: one year great, then next year not-so-hot. 2015 was a not-so-hot year. 2016 will be awesome!

The illustration below is from NASA’s Tumblr page. It’s shows the disk size of Mars, as viewed through a telescope. Mars appears larger in a telescope because the distance between Earth and Mars will be decreasing rapidly over the coming months, as we sweep up behind Mars in orbit and prepare to go between it and the sun in May.

I hope the chart below gives you an inkling of the excitement to come in early 2016, regarding the planet Mars!

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You’ll be amazed at the changes you’ll see in Mars during 2016. January through December are all prime Mars observing months. Between January and May next year, Mars triples in apparent diameter as its orbit around the sun brings it closer to Earth. Illustration via nasa.tumblr.com.

If you had a telescope, you could amaze yourself by watching this planet in the months ahead. Between January and May, 2016, Mars triples in apparent diameter as our mutual orbits around the sun brings our world closer to Mars. Without a telescope, during 2016, you’ll see Mars brighten rapidly – get as bright as Jupiter – then fade again. Illustration via nasa.tumblr.com.

Bottom line: Watch for the moon and Jupiter, as they shine close together on the sky’s dome from late night until dawn on December 30-31, 2015. Also … a preview of Mars in 2016!

When can I see all five visible planets simultaneously?

Bruce McClure