Stellar Vista Observatory Sky Report

John Mosley

March 13 – 19

The Sky Report is presented as a public service by the Stellar Vista Observatory, a non­profit organization based in Kanab, Utah, which provides opportunities for people to observe, appreciate, and comprehend our starry night sky. Additional information is at www.stellarvistaobservatory.org. Send questions and comments to John@StargazingAdventures.org.

This week we’re happy to see three planets in the evening sky since by month’s end we’ll be down to two.

The brightest planet – and the brightest astronomical object in the night sky except the moon – is brilliant Venus. Venus was behind the sun last fall and it very gradually reappeared to view beginning in December, gaining altitude slowly day by day. Now it’s high in the west as the sun sets, about 33° above the horizon or more than a third of the way to overhead at sunset. Venus is on the far side of the sun, 118 million miles from earth, and telescopically it looks like a tiny featureless nearly-full moon. It’s much prettier without a telescope than with, and it’s bright enough to photograph with most cameras.

Half-way between Venus and the sun, as we see it, is the giant planet Jupiter. It’s been in the evening sky all winter but this is our last week to see it as it slowly slips behind the sun. Actually Jupiter isn’t doing much; it orbits the sun so slowly that it takes 12 years to move once around the sky, which is the rate of one constellation of the zodiac in one year. The earth is moving 12 times faster – once around the sun in one year – so it’s really our orbital motion that makes Jupiter set four minutes earlier each day. In two weeks Jupiter will disappear behind the sun, not to reappear until May in the morning sky. Jupiter is 1/16 as bright as Venus and only 7° high 45 minutes after sunset so finding it is for people with binoculars who like a challenge.

Mars orbits the sun at a similar speed as the earth so it will linger in the evening sky until July, moving eastward through the constellations of the zodiac – Taurus, Gemini, and Cancer, while crossing the winter Milky Way. As winter began Mars was one of the brightest objects in the sky but now it’s lost among the many brighter stars near it, and you’ll want to know the constellations to pick it out. It’s nearly overhead as twilight ends. Face south then, and Mars is 20° directly above Betelgeuse, the orange star in Orion’s left (easternmost) shoulder as we see him. Betelgeuse is slightly (¼ magnitude) brighter – can you see the difference? Mars is in easternmost Taurus, near the Bull’s horns, and in front of the billions of stars that make up the Milky Way. It crosses into Gemini next week, using modern constellation boundaries, and with a telescope or binoculars you can watch it approach the bright star cluster M35, which it passes at month’s end. Mars’ motion is ½° per day, fast enough to see it move against the many background stars night by night with any telescope and even binoculars. Little Mars is 125 million miles from earth, nearly the same distance as Venus, and too small to see surface features through a telescope.

Stellar Vista Observatory provides portable telescopes and tripod mounted binocular kits on loan for free to residents and visitors in Kane County. Enhance your enjoyment of the night sky! To learn more, request a loan, or attend one of SVO’s free public star parties for 2023, visit https://stellarvistaobservatory.org/ or drop in to the Kane County Office of Tourism.