I’m leaving Substack, An incredible photo of a comet and the Horsehead

January 25, 2024   Issue #674

About this newsletter

Ooo, meta

If all goes well today and tomorrow, this will be the last Bad Astronomy Newsletter issue I’ll be sending via Substack.

<tl;dr: No action is required on your part; just sit back and relax and the BANs will continue to be sent to you, just through Beehiiv instead of Substack.>

As you may be aware, Substack has a Nazi problem. They allow and even promote far-right hate on the platform, and when confronted on it they doubled down. In my opinion this is NOT a free speech issue at all; your right to free speech in the US is only that the government can’t abridge it. If you own a bar or a restaurant and someone starts yelling Nazi slogans, you have the right to throw them out. I’d go so far as to say you have the moral obligation to throw them out.

Substack has abrogated this duty. They’re becoming a Nazi bar.

This has caused a lot of newsletter writers to leave the platform. Some folks have argued that staying allows one to fight, giving you a voice that has leverage. I had my doubts, and after talking personally to one of the founders of Substack I can see I was right. They will not change their stance on this.

My voice is not swaying them, so maybe my actions together with so many others will.

After this issue of BAN is sent out I will begin in earnest the process of migrating the newsletter to Beehiiv, another email newsletter platform where the CEO (in a Zoom call I was part of) was unafraid and unhesitant to say they ban Nazis (and other hateful people).

What does this mean for you, the reader? Hopefully, nothing! Once the database is migrated, all the subscriptions will move to Beehiiv, which like Substack uses Stripe to process payments. Your subscriptions will simply be taken up by Beehiiv, and things will proceed as they did before. If you have a monthly or annual subscription it will continue as if nothing happened. Free subscribers will also simply continue getting the free issues as well.

I suppose one thing you can do if you want is to make sure beehiiv.com is whitelisted with your email software. That way you can make sure he newsletter isn’t sent to spam.

If you don’t get your BAN issues as usual, then 1) check your spam/trash folders to see if it’s there and make sure to mark it as safe, and/or b) send me an email ([email protected]) and let me know so I can see what’s what.

You’ll also notice the formatting of the newsletter will be a little different, because of course Beehiiv has different tools to set up how the issues look. But other than that you’ll still get the usual astronomy, science, humor, and related sense and nonsense from me as always.

Thanks to everyone for supporting me through this, and I hope you continue to subscribe.

Pic o’ the Letter

A cool or lovely or mind-bending astronomical image/video with a description so you can grok it

If you’ve been reading my newsletter for any length of time, you know how much I admire Damian Peach’s astrophotography. His work with solar system objects is amazing.

He sent me an image he took on the last day of 2023, and it made me smile. It shows the long-period comet C/2017 K2 (PanSTARRS), which on that evening happened to be in the sky very close to the iconic Horsehead nebula. The shot is, of course, incredible (click that to see it in more detail than I can display here). But I have to admit: It took me longer than I expected to actually find the comet in the photo!

I’ll let you dig for it. When I saw it though I laughed: it couldn’t have been better hidden if it were actively camouflaged. [Note: There’s a very faint satellite streak going from the lower center-left to the upper right; don’t confuse that for the comet.]

The Horsehead is a wonder. The bright star above it is Alnitak, the eastern-most (on the left, for northern hemisphere observers) star in Orion’s belt. The not-quite-as-bright star to the right is Sigma Orionis. The nebulosity is pretty faint, and usually needs a telescope and decent camera to see at all. But the dark, dense, cold and dusty gas making up the Horsehead is silhouetted against the brighter material, and the resemblance to a knight in chess is amazing.

The comet K2 is on an ever-so-slightly hyperbolic orbit, which is very interesting indeed. Objects on hyperbolic orbits are moving faster than escape velocity, so they’re not bound to the Sun. But (according to Wikipedia, which got its info from NASA/JPL) this one is weird: It was on a hyperbolic path on its way down from the depths of space, but the gravitational influence of the planets changes it to a barely elliptical orbit on its way out! That means it will stay bound to the Sun, on a trajectory that won’t bring it back this way for many thousands of years. Some astronomers made simulations of its orbit and showed that it may have actually started off as bound to the Sun, but there’s also a chance it was an interstellar object like ‘Oumuamua as recently as three million years ago and was captured by the Sun. That’s pretty cool.

K2 was nearly 560 million kilometers from Earth when Damian took the photo above, on its way out to the Deep Black once more. We won’t be seeing it again for a long, long time… but as we get better at scanning the skies, we’ll see lots more like it. Hopefully we’ll learn more about how their behavior, including how their orbits change with time. Comets are all pretty weird, but some are weirder than others. If we have good enough data on a lot of them, maybe we’ll start to really understand what’s weird and what isn’t.

Et alia

You can email me at [email protected] (though replies can take a while), and all my social media outlets are gathered together at about.me. Also, if you don’t already, please subscribe to this newsletter! And feel free to tell a friend or nine, too. Thanks!