Bad Astronomy Newsletter #15
June 4, 2018 Issue #15
|Phil Plait||Jun 4, 2018|
If you don’t subscribe you can still pardon yourself.
What I’ve recently written on the blog, ICYMI
Thursday, May 31: The Tarantula Nebula is very, very big (a jaw-dropping and HUGE image of a star-forming nebula. Yeah. Click that.)
Wednesday, May 30: Two planets discovered: One by gravity, one by accident [Part 2]
Tuesday, May 29: Two planets discovered: One by gravity, one by accident [Part 1]
Monday, May 28: Al Bean, Apollo 12 moonwalker, has died
Where I’ll be doing things you can watch and listen to
This isn’t so much an appearance by me but by something I work on: CBS has announced that the season 2 premier of “Salvation” is June 25! I’m the tech consultant on the show, which is a political thriller about the government’s reaction to an impending impact by a giant asteroid. It’s a lot of fun to work on — I wrote about it last year for the first season.
Follow o’ the Letter
Someone you should follow on social media
My friend Alie Ward is not a scientist. But you’d never know.
After all, she loves (like LOVES) insects, and talks about them a lot in interviews and various podcasts she’s hosted. Oh, and then there’s this from her website:
Alie Ward is a Daytime Emmy Award-winning science correspondent for CBS’s "The Henry Ford's Innovation Nation with Mo Rocca,” and appears on the Science Channel series "How to Build Everything,” Cooking Channel's ongoing show "Unique Sweets," and GE's series "In the Wild" with co-host Adam Savage of Mythbusters.
So while she’s not technically a scientist, she does a lot of the heavy lifting out there in electron-land getting science out to the folks who also love it — or maybe who don’t know they love it yet.
[The reason I dig her so much: Alie Ward’s brain — and yes, it really is her brain; I stole it from her Instagram page so don’t tell her. Credit: Alie Ward]
Currently her big thing is doing her podcast, “Ologies”, where she interviews scientists, researchers, and or just people who study various –ologies (biology, sexology, ornithology… you get the idea). This is a brilliant idea for a themed podcast! And she’s talked to some folks I like, such as cosmologist Katie Mack (in a two-parter) and volcanologist (and Congressional candidate) Jess Phoenix (whom I featured in this newsletter). No joke, this is one of my favorite podcasts right now; I look forward to longish drives so I get a chance to listen. Her schtick is being an ingénue while talking to experts, and it works. I especially like her asides — like audio footnotes — explaining something that was just said or just happened during the interview.
Pic o’ the Letter
A cool or lovely or mind-bending astronomical image with a short description so you can grok it
[NGC 5398, an average spiral galaxy, except for that jaw-dropping nebula off to the side. Credit: ESA/Hubble & NASA]
The galaxy NGC 5398 is an odd duck, a barred spiral about 55 million light years away on the constellation of Centaurus. The spiral arm structure is rather weak and faint, and the bar — the rectangular structure going across the center — is large and obvious.
Unlike most spirals, the galaxy doesn’t show much evidence of star formation; if so you’d see lots of pinkish gas clouds in the arms in this Hubble Space Telescope shot, and the arms would look decidedly blue due the presence of lots of young hot stars.
And then you look to the lower left, and holy cow, it has a whopping huge star-forming cloud there! That nebula is called Tol 89, and it may be something like 6,000 - 7,000 light years across (making it ridiculously huge). The amount of light it gives off in the ultraviolet indicates there may be more than 4,000 massive O-type stars in it, which is mind-boggling.
If you replaced the Orion Nebula (at a distance of about 1,300 light years) with this monster, Tol 89 would appear 300 times bigger — it would extend a quarter of the way around the sky! — and I’m not sure just how bright it would be. The Orion nebula is visible to the naked eye, so this thing would be bright. It also may have a billion times the mass of the Sun in just hydrogen gas in it. Everything about this nebula is crushing my brain. It’s one of the largest active star-forming regions we know of in the Universe.
Tol 89, interestingly, is right at the end of that nuclear bar. Is that a coincidence? It’s unclear. Bars like that form in some spirals due to the weird overall gravitational field of billion s of stars affecting one another, and bars tend to funnel gas and stars toward the galactic center. Some galaxies due have big nebulae at the bar tips, but in general not ones like NGC 5398.
I hope more astronomers observe this weird system (I didn’t find a lot of papers about it published). I’d love to see more information about this thing, especially why such a milquetoast galaxy harbors such a nebular beast.
You can email me at firstname.lastname@example.org (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!