Minnesota Starwatch: October 2017

October is known for its clear, crisp weather, so let’s hope the pattern holds.

Mars joined Venus in the morning sky about a month ago. Mars is climbing as Earth starts to catch up to it in the orbital race, while Venus is slowly dropping as it gets ready to sail behind the sun. On the 5th, the planets slip by each other, coming within half a full-moon width. Look low in the east about an hour before sunrise; Venus will be the slightly higher and brighter object.

While you’re at it, turn to the west to see the almost full moon getting ready to set, and take a gander at the winter constellations in the south. Southeast of Orion’s hourglass form, Sirius, the brightest of stars, shines from Canis Major, the big dog. On the evening of the 5th, the harvest moon rises to light fields for farmers bringing in their crops.

As the days go by, Mars climbs higher as the moon wanes to a thin crescent. The morning of the 17th, one cusp of the moon points to Mars. The next morning, the older, thinner moon rises below Venus to complete a pleasing stack of one moon and two planets.

Jupiter disappears into the sunset in the first few days of the month, but fear not. The king of planets reappears in the morning sky next month, and just like Mars, it’ll pass close to Venus as it climbs. And because it climbs much faster than Mars, it sweeps very close to Mars, too; that happens in early January. All in all, morning viewers have plenty to look forward to.

In the evening sky, look for the Great Square of Pegasus high in the southeast or south. Below it, the Circlet of Pisces is fun to find, and that lone bright star low in the south is Fomalhaut, the mouth of Piscis Austrinus, the southern fish.

The University of Minnesota offers public viewings of the night sky at its Duluth campus. For more information and viewing schedules, see the Marshall W. Alworth Planetarium at: d.umn.edu/planet.—Deane Morrison