For as long as I remember there have been frequent forecasts of bright comets coming to our skies. Often, many predictions go way over the top, like “Comet of the Century will Light up the Sky.” When these overblown expectations aren’t met or don’t even come close, folks understandably are discouraged and even cynical, and who can blame them?

Most of these headlines are produced by people who care more about grabbing your attention than providing accurate information. Unfortunately, that happens more and more with the plethora of available media, no matter what the subject is.

Comet Tsuchinshan-ATLAS shows great promise though. Calling it the comet of the century is a bit much since, for one thing, there are more than 75 more years left of the present century. Nonetheless, Tsuchinshan-ATLAS has exceeded the original brightness forecasts. For the last several weeks, folks, mainly in the southern hemisphere, have been dazzled by the comet being visible to the naked eye. Beginning this weekend, it’ll be our turn in the northern hemisphere as the comet just made its closest approach to Earth, about 70 million miles. For the next seven to 10 days, Tsuchinshan-ATLAS should be at its brightest, possibly visible to the naked eye, especially in the darker countryside sky.

c2 j22 15x25

This weekend, look for Tsuchinshan-ATLAS in the very low western Butler sky toward the end of evening twilight. You’ll need to be observing in a place where the western horizon will be as flat and treeless as possible. A tall hilltop would be an excellent place to go.

On Saturday evening between around 7:15 to 7:30 p.m., the comet will be barely above the horizon and may be lost in the glow of twilight.

On Sunday evening around 7:30 p.m., Tsuchinshan-ATLAS will be a little higher above the horizon and easier to see. It’ll resemble a fuzzy star with a tail pointing to the upper left. The tail may have some decent length to it!

To help you better find it, hold a clenched fist out at arm’s length. The comet will be almost two fist-widths or 20 degrees to the lower left of the bright star Arcturus, the brightest star in the evening sky. Make sure you don’t mistake the planet Venus for Arcturus. Venus is much brighter than Arcturus but is practically on the horizon.

Also, make sure you look as early as you can for the comet because it’ll be lost in the blur near the horizon on its way to setting by around 8 p.m.

As you can see in the diagram, as the week goes on, Tsuchinshan-ATLAS will start the early evenings this week higher and higher in the west-southwestern sky.

During the same time, though, as this week and the rest of October continues, the comet also will get fainter and fainter as it travels farther and farther away from Earth, so again, this week, the comet should be at its brightest. Let’s hope for clear enough skies. I want to emphasize that no one knows exactly how bright Tsuchinshan-ATLAS will be or how long the tail will be. Let’s hope for the very best!

One thing not in our favor this week is that there’ll be a lot of moonlight in the evening sky with the official full moon on Thursday. The good news though is that the moon will be on the opposite side of the sky over in the east while the comet will be in the west.

Another to keep in mind is that the photos you see of comet Tsuchinshan-ATLAS in the media will, in most cases, be brighter than they’ll appear visually. That’s because many of the exposures are multi-seconds long allowing more light to be accumulated. Our eyes don’t work that way though. You can prove this yourself by taking a photo of the comet with your smartphone. Most cameras in phones automatically take one to three-second exposures at night. I can almost guarantee you comet photo will be brighter than reality.

Comets like Tsuchinshan-ATLAS are cosmic mountain-sized dirty snowballs of ice, dust, and rock that are remnants from the formation of our solar system more than four and a half billion years ago. Most comets spend their entire lives in the super frigid outer reaches of the solar system.

Quite frequently comets break loose and are drawn by the sun’s gravity toward the inner solar system. Depending on their trajectory most comets get caught in very elongated orbits that take them close to the sun and then whip them back out to deep space, not returning in some cases for hundreds or even thousands of years.

An excellent example is the famous Haley’s Comet, which has a 75-year orbital cycle. Many times though comets get entirely obliterated by the sun’s intense radiation. Some even crash into the sun! That’s not the case with Comet Tsuchinshan-ATLAS. It’s alive and well and is believed to have an over 80 thousand years long orbit around our home star!

As comets draw closer to the sun like Tsuchinshan-ATLAS has, these dirty snowballs start melting, vaporizing the ice and releasing debris. Comets then begin developing a giant cloud around the nucleus called a coma, and the tremendous solar wind pushes gas and debris back, forming the comet’s tail that can really get stretched out millions of miles.

By the way, if you think Tsuchinshan-ATLAS is quite a mouthful for the name of this comet, its formal astronomical name is C/2023 A3 Tsuchinshan-ATLAS. It’s a hyphenated name because is discovered nearly simultaneously by an observatory in China and ATLAS, a network of four telescopes that continually scan the heavens for asteroids and comets that could potentially collide with Earth.

I hate to bring this up, but historically, many cultures viewed comets as harbingers of war, famine and other calamities. I hope and pray this isn’t the case with Tsuchinshan-ATLAS, especially considering what’s been happening in the world lately.

Try to forget about that, though, and enjoy Tsuchinshan-ATLAS!

Mike Lynch is an amateur astronomer and retired broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul. He is the author of “Stars: a Month by Month Tour of the Constellations,” published by Adventure Publications and available at bookstores and adventurepublications.net. Contact him at mikewlynch@comcast.net.