The Sun and its retinue of planets live in a pretty quiet part of the galaxy. We’re not near any huge star-forming gas clouds (called nebulae), for example, which is a good thing. These stellar factories — like the Orion Nebula — make stars of all sizes, from wee red dwarfs to massive blue O-type stars, and those latter are dangerous.

For one thing, when they die they explode, so that’s not great if you want have a nearby planet that supports life. But also, just when they’re hanging around and doing O-type star stuff, these massive stars are incredibly hot and luminous, irradiating their environs, blasting them with intense energetic ultraviolet radiation. Again, a planet immersed in this soup doesn’t sound conducive for, well, us.

UV light at those levels can destroy lots of ingredients needed for life, like water and various carbon-based molecules. Yet we think the Sun was born in just such an environment. How can that be? Is it possible for planets like Earth to form in nebulae where these lethal beasts are abundant?

To find out, astronomers pointed JWST at the kinda sorta nearby nebula NGC 6357. At 5,700 light-years from us, it’s close enough to study at good resolution, but not so close it presents a danger (the Orion Nebula is a quarter that far away, for comparison, and we’re fine). Why JWST? Because a lot of those biologically necessary molecules absorb and emit light in infrared wavelengths, and that’s where JWST is tuned. Also, because we need to see material very close in to the stars forming there, so high resolution (think of it as very keen eyesight) is needed as well.

NGC 6357 is perfect for this. It’s young, only about 1.5 million years old, so there are a lot of stars forming there that still have protoplanetary disks, the flat, swirling disks around very young stars from which planets are made. These disks get used up to make planets pretty rapidly, so you want young systems to investigate. Also, the nebula’s youth means that the short-lived O-type stars are still around. A dozen or so of them flood the nebula with UV light, and it’s very difficult for any planet-forming stars there to avoid it. The stars with disks are scattered around, getting irradiated at different levels, making it easier to compare them, too.

So the astronomers took spectra of one of these disks in a stellar system called XUE1 (they plan on observing more in time). This is actually a trinary star system, where a massive star orbits a binary pair of stars, both of which are very roughly twice the mass of the Sun. The disk they see is circling one of those binary stars. Given its location, they find it very likely it’s been bombarded by radiation from nearby very massive stars.

And what did they find? Water! And carbon monoxide! And carbon dioxide, hydrogen cyanide (HCN), and acetylene (C2H2) as well, all ingredients that we think helped life on Earth get its start, and all ingredients that, you’d think, would get shattered by extreme ultraviolet radiation. Yet there they are. [Link to research paper]

The astronomers note that it’s possible the star is shielded from the external radiation by thick dust, which is opaque, but they think it’s unlikely. It’s also possible the hot, massive stars in the cluster are farther from XUE1 than they assume, due to lack of detailed knowledge of just where those stars are in 3D space (we can only get approximate distances, and if XUE1 is located closer to us or farther away, it might be a bit farther out from the cluster, so more distant from the irradiating stars). Clearly, they need to observe more of these protoplanetary stars to build up some statistics, but this first result is pretty provocative. If correct, it means that it’s apparently possible for these molecules to exist just fine, even when in the incredibly hostile environment of a huge star-forming nebula. That’s very cool.

It also means that planets like Earth could possibly form there and get a decent start on life despite the obvious issues. This is interesting because, again, we think the Sun and its planets formed in such an environment, and also because it means that Earth-like planets might be even more common than we thought. To be clear we need lots more observations of disks to make sure this result isn’t a fluke, but it’s heartening. 

During the last week of this month I am doing a whirlwind tour of Indiana (though kicking it off in Cincinnati) to give a lot of talks about the upcoming total solar eclipse that will occur on April 8. I’m doing five public events and a handful of private ones at schools, too.

This eclipse will be amazing, with people along the very centerline of the path getting just over four minutes of totality! It passes over a lot of cities, including many in Indiana, so if you’re in the area come see me give a presentation on how eclipses work, why they’re so cool, how to safely observe this one, and maybe even do some citizen science along the way. My talks are meant to be understandable and fun. I make a lot of jokes. Like, a lot.

Here’s the schedule, including links to more info and how to register. Most are free, but you still have to get tickets.

• Feb. 25, 2024: Sponsored by the Cincinnati Observatory, I’ll be speaking at the Clark Montessori Cafeteria. You can get more info and register here. Tickets are $20/adult, $10/child, $5 each additional child to join, which includes 2 pairs of eclipse glasses and a visitor pass to the Observatory for each attendee. It’s a fine old observatory, and I’m hoping to get a chance to see it again while I’m there.

• Feb. 26, 2024: I’ll be at Indiana University Kokomo speaking at 7:00 p.m. This is free to the public, and you can get more info and register here. The Kokomo Tribune did a nice interview with me, too (it’s behind a paywall but Yahoo has a copy online as well).

• Feb. 27, 2024: I’ll be at Indiana University East in Richmond. The talk’s at 7:00 p.m. and is free and open to public. Info and registration here. 

• Feb. 28, 2024: Keeping up the IU streak, this one’s at Indiana University Bloomington at 6:00 p.m. There’s a student dinner and then a meet and greet, which’ll be fun (I love talking to students). Info is here.

• Feb. 29, 2024: Finally, I’ll be at the Myriad Brew Pub in Evansville, Indiana at 6:00 p.m. talking about the eclipse. I’ve done a few talks in pubs and they’re always fun; it’s super informal, people are in a jolly mood, and the questions can be all over the place.

I hope to see you Hoosiers there!

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!