What? There’s a comet coming?
In fact, it’s already here. Oh yes, it seems that 2024 may not just be the year of a terrific solar eclipse and spectacular outbursts of northern lights (and maybe, just maybe, a nova.) In morning twilight, if you live in the right latitudes, an ever-brightening comet can apparently be spotted right now. I haven’t seen it yet, but I’m hoping to get a chance.
Nothing in cometary life is guaranteed; comets can fall apart unexpectedly, or fail to brighten as expected. So far, though, Comet C/2023 A3 Tsuchinshan-ATLAS is looking promising; its tail may soon be longer than its name.
The comet will soon be seen in the evening sky. But for the next few days, it is visible in the morning sky during the last hour before sunrise. Depending on
- which day it is — the comet moves noticeably across the sky from one day to the next — and
- your latitude — close to the equator is better, and slightly south of the equator is best —
you may have an opportunity to find it. It will not be easy, as it will be close to where the Sun is soon to rise, and it is not bright enough to shine easily through the morning twilight. (Perhaps binoculars would help; I’m not sure.) But photographs show that it can be found, with some effort.
You will definitely need a very low and clear horizon to see it this week. To get a sense of how high it might be above an ideal, unencumbered horizon, look at this informative chart made by Nick James (British Astronomical Association) and posted at spaceweather.com. It shows the comet’s altitude in degrees above the horizon, about 20 minutes before sunrise, for various latitudes (as labeled in the upper left corner; “+” means north, “-” means south), for each day over the next two weeks or so. In the US, you are best off in the next couple of days, and your chances are better you’re in the southern half of the country, around 30-35 degrees latitude or less. Much of northern Europe is probably out of luck for now. Over the coming few days, Africa, South and Central America, Australia and southern Asia should have the best views. Then the comet leaves the morning sky.
The comet may well be more easily and more conveniently visible in mid-October’s evening sky, so consider this the first but perhaps not the only opportunity to see it. Let me know if you manage to spot it this week!
