Categories: Sky Reports
This week we’ll focus on the planets.
The brightest planet in the evening sky is the king of the planets, Jupiter. You’ll see Jupiter low in the southeast as darkness falls, and high in the south around 1 a.m. No star or other planet is brighter.
This is a good week to look at Saturn through a telescope because it’s at its highest, 1/3 of the way up the southern sky, at about 10 p.m. By then the ground has cooled from the heat of the day and atmospheric turbulence is reduced. Notice the angle the rings make to our line-of-sight. Our earth is tilted on its axis by 23½°; Saturn is tilted 27°. Since Saturn orbits the sun in almost 30 earth-years (which equals 1 Saturn-year), the tilt that we see from earth ranges from 27° (when they’re at their widest open) to 0° (when they’re edge-on); at present the tilt is 14° and decreasing. We now see the northern hemisphere of Saturn and the north side of the rings. You’ll need a telescope with at least 30-power to see the rings, and when you do see them make a sketch of their orientation. Compare in only 3 years when they’re nearly edge-on. In 3 more years (2028) they’ll be back like they are now, but we’ll then be looking at their south side. Wikipedia can give you the details I don’t have space for.
On the 5th Saturn is 7° to the upper right of the moon and on the 10th Jupiter is 5° to the upper right of the moon.
On October 6th the nearly-full moon sits midway between Jupiter and Saturn. That’s midway as seen on the dome of the sky, but of course they’re at vastly different distances from us and from each other. Think of their distances in terms of the speed of light: by light the moon is 1¼ seconds away, Jupiter is 33 minutes away, and Saturn 1 hour 17 minutes away. And of course the stars “near” them are many light years distant. For example, the star just below the moon, with the unusual name Skat (Arabic for “shin”), is about 110 light years away.
The 3rd planet visible tonight is Mars, which rises before midnight. The earth is catching Mars on an inside orbit, so it’s slowly growing brighter as we approach it. Mars is in Taurus, where it’s equi-distant from the orange stars Aldebaran and Betelgeuse and is slightly brighter than either (only the white star Sirius is brighter than Mars). Mars is at it’s highest at 6 a.m. when it’s due south and nearly overhead. Mars is almost close enough to see to see its major surface features https://stellarvistaobservatory.org/wp-admin/through an excellent telescope.
From roughly 11 p.m. until 3 a.m. you can see these three planets at the same time.
You might spot elusive Mercury 45 minutes before sunrise, when it will be only about 8° above the horizon, but compliment yourself if you do.
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! For details or to request a loan, visit https://stellarvistaobservatory.org/discover-the-night-sky/ or drop in to the Kane County Office of Tourism.
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.
John Mosley was Program Supervisor of the Griffith Observatory in Los Angeles for 27 years and is the author of “Stargazing for Beginners” and “Stargazing with Binoculars and Telescopes”. He and his wife live in St. George where he continues to stargaze from his retirement home while serving on the advisory committee for Stellar Vista Observatory.