Our winter evening sky is rich with planets doing interesting things. I wrote up a summary for our Chrysalis families. Then I thought you might also be interested. So here is the same slightly-revised article for you.
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Venus, the third brightest object in the sky (after the Sun and Moon) is radiant white. Currently it is easily obvious high in the southwestern sky after sunset. Over the next two months, however, Venus will both dim and sink lower in the western sky until it disappears in March. By the end of this school year, Venus will become the “Morning Star” in the eastern sky, easily visible to those who arise before sunrise. An astronomical brain-teaser: Why does Venus alternate back and forth between being the “Evening Star” in the west after sunset and the “Morning Star” in the east before sunrise?
Jupiter is the next brightest object after Venus. It’s appears white and is up in the eastern evening sky “above” Orion. With binoculars, you might be able to see its four largest moons in a line. Galileo tracked their movement over many days and realized they were orbiting Jupiter. https://images.fineartamerica.com/images-medium-large-5/galileos-paper-on-jupiters-moons-royal-astronomical-societyscience-photo-library.jpg Jupiter orbits the Sun every ten years so next winter, you will see it that it has significantly moved to the east and is no longer close to Orion.
The bright star to the lower left of Orion is Sirius, the brightest star in the sky.
Mars rises later in the eastern evening sky. The distance between the Earth and Mars fluctuates dramatically (from 35 million out to 250 million miles) depending on where we both are in our orbits. Therefore, the apparent brightness of orange Mars fluctuates. Right now, we are at our closest so Mars is bright. It will grow dimmer through this school year as we move further apart. Notice its position: to the left and lower than a pair of bright stars (Castor and Pollux in Gemini, The Twins). Mars orbits the Sun about every two years so by the end of the school year, Mars will no longer appear close to Gemini.
Saturn is also up in the evening sky but because it is much further away, it is not as bright as the other visible planets. Look online for maps that will show Saturn’s current position (right now between Venus and Jupiter). Currently, Saturn’s rings are on edge to us, hence invisible.
Moon – Notice how both its phase and position (the two are related) change nightly. Use the visible planets to more precisely track its position.
On January 13th, the full Moon will pass in front of Mars. Mars will disappear behind the Moon left side and reappear on its right side about a half-hour later. This is called a lunar occultation and watching it gives you a chance to see how “quickly” the Moon is steadily orbiting us. This occultation will be visible in western Africa and most of North America. Check your local news sources for local times. It will be around 6 PM PST for California.
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