I got up early Sunday morning (Oct. 17) to check on Comet Leonard in Ursa Major. Although the comet requires a medium-size telescope to see right now it should become visible in binoculars by late November and with the naked eye in early December. I'm happy to report that Leonard is already looking good despite its considerable distance from Earth of 186 million miles (300 million km). When closest, on December 12, it will pass just 21.7 million miles (34.9 million km) from your doorstep. Through my 15-inch scope it was a fuzzy, 11.5-magnitude tuft of light shaped like a dandelion fluff with a bright, seed-like head and short, faint tail.
Sometimes it's what you don't plan on seeing that makes standing under the stars such a blast. Like the four bright, swift meteors that shot out of Orion over the space of three minutes as soon as I walked outside and looked up. When I followed their trails backwards they all pointed to Orion's club, a sure sign they were members of the annual Orionid meteor shower. The shower is active from late September to mid-November and peaks later this week during the early morning hours of Thursday, Oct. 21.
Unfortunately, the moon will be full at that time. Meteor showers take a major hit around the time of full moon because its glare drowns out the fainter members. Be on the lookout anyway. You'll still see the bright ones. At peak, up to 20 meteors per hour will fly from Orion on Thursday the 21st between about 2-6 a.m. local daylight time. Orionids are fragments spalled from Halley's Comet that follow its orbit around the sun. Every October, the Earth passes through the comet's orbit, and these otherworldly shards strike the atmosphere at high speed (Orionids are REALLY fast!) and make meteor streaks.
Just before the start of dawn, the very bottom of the northern sky began to glow with aurora. For the next half-hour, a soft, faint light danced there. Then around 6 a.m., a more purposeful glow gathered at the eastern horizon. Dawn. For the next 20 minutes both were visible simultaneously. I smiled at the sight because it all made sense.
The aurora borealis gets its name from Aurora, the Roman goddess of dawn and Borea, the Greek word for the northerly wind. Galileo coined the term in 1619 because northern lights resembled an early dawn in the northern sky. Like many of his time he ascribed their cause to sunlight reflecting off the atmosphere.
The Italian scientist was right in identifying the sun as the instigator. But auroras shine not through reflection but by direct interaction between subatomic particles shot out by the sun and oxygen and nitrogen atoms in the upper atmosphere. A typical aurora hovers about 60 miles (100 km) overhead.
It gave me joy to see both the goddess and its namesake hand-in-hand painting the horizon. Although the lights aren't expected tonight, there's a small chance for activity Monday night the 18th. Meanwhile, Venus shines at dusk in the southwestern sky and shines about 2° northeast (above and left) of Antares, the brightest star in Scorpius, tonight.
Antares is normally easy to see, but low altitude and twilight will make its splendor suffer. I promise you this at least. You'll have no problem spotting it in binoculars. Point at Venus and use the map (above) to look in the right direction for the star. The best time is between 45 minutes and an hour after your local sunset.
"Astro" Bob King is a freelance writer for the Duluth News Tribune. Read more of his work at duluthnewstribune.com/astrobob.