Arizonans can see year’s brightest comet, 46P/Wirtanen, this week
Dec 12, 2018, 2:00 PM
The last time that a bright comet graced Arizona skies was back in 1997 with the passage of comet Hale-Bopp.
Comet Hale-Bopp was one of the brightest comets ever to be seen in the skies of this great state, with some of the darkest skies in the entire nation.
Many back then wondered when that comet would finally fade from our skies after being easily seen for many months. Since then, we have had a long stretch of drought when it comes to decent naked-eye comets.
But now welcome in comet 46P/Wirtanen.
Comet 46P/Wirtanen is the 46th known periodic comet. It was discovered back in 1948 by astronomer Carl Wirtanen at the Lick observatory in California. Comet 46P/Wirtanen is a small comet by comet standards, being maybe a mile in diameter.
The comet orbits the sun with a period of some five years and is a member of the “Jupiter family” of comets. These are comets whose orbits reach out to Jupiter and are subject to changes in their periods of revolution, due to the planet’s gravity.
Comet 46P/Wirtanen passes far enough from the Earth to keep us out of harms way, but on Sunday around 6 a.m. Arizona time, the comet will come within 7,199,427 miles to us, making it one of the closest passes of any known and recorded comet to date!
The near approach of the comet will help with viewing it in our Arizona skies, if you know just when and where to look.
As with many comets, they are usually faint and require a pair of binoculars to view them with.
Comet 46P/Wirtanen is no exception to this rule, as the comet from the darkest and moonless skies of Arizona appears to be as large, but faint.
The comet will begin to move higher in the sky during this week and will pass very close to the star cluster known as the Pleiades on the evenings of Dec. 15 and 16.
Here is the truth: Many websites suggest this comet may be bright and easy to see from just about any location. This is not true and knowing that this comet is coming close to Earth — and will be one of the closest in some time — may give the general public the wrong idea.
Finding it will be a bit of a challenge for some, but it will be a great way to learn about the many wonders of our great Arizona night skies.
Just in case you don’t get to see Comet 46P/Wirtanen, Geminids, a decent meteor shower, will peak on Dec. 13 and 14. Look to the northeastern sky after 9 p.m. both nights to see some of the year’s best meteors, also brought to you from a distant comet/asteroid.
To print your own monthly star chart, click here.
To view satellites/dates/times of passage, click here.
Listen to the Dr. Sky Show on KTAR News 92.3 FM every Saturday morning at 3 a.m.