Barbara Ryden
@bsryden.bsky.social
Writer of astrophysics textbooks, servant to cats
Happy Fat Bear Week to those who celebrate!
September 28, 2025 at 7:49 PM
Happy Fat Bear Week to those who celebrate!
I'm not certain this is the best possible epigraph for a chapter on accretion, but I was feeling Rabelaisian when I chose it.
September 22, 2025 at 6:32 PM
I'm not certain this is the best possible epigraph for a chapter on accretion, but I was feeling Rabelaisian when I chose it.
Although a quotation about the incomprehensibility of turbulence (even with divine intervention) is often attributed to Werner Heisenberg, this statement by Horace Lamb seems to have priority.
![Epigraph to Chapter 6 of Astrophysical Has Dynamics:
It was at a meeting of the British Association in London in 1933
that I remember that [Horace] Lamb remarked, "I am an old man
now, and when I die and go to Heaven there are two matters on
which I hope for enlightenment. One is quantum electrodynamics,
and the other is the turbulent motion of fluids.
And about the former I am really rather optimistic."
Sydney Goldstein](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreig5xxwb2nmlj5rjv3kl252pdwi6bqxe5yfifdartlp4kcbaql3at4@jpeg)
August 17, 2025 at 6:15 PM
Although a quotation about the incomprehensibility of turbulence (even with divine intervention) is often attributed to Werner Heisenberg, this statement by Horace Lamb seems to have priority.
Roundhay Scene (1888)
July 23, 2025 at 11:51 PM
Roundhay Scene (1888)
For balance, a chapter that contains Maxwell's Equations must start with Maxwell's Poetry.
![Epigraph to Chapter 5 (Mangetohydrodynamics):
The world may be utterly crazy,
And life may be labour in vain;
But I'd rather be silly than lazy,
and would not quit life for its pain.
-- James Clerk Maxwell [1858]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreifskr3623bxavjwyf4reuqnt76hggu5g4whpvyjijts5o52fmelj4@jpeg)
July 14, 2025 at 6:30 PM
For balance, a chapter that contains Maxwell's Equations must start with Maxwell's Poetry.
I continue my cinematic era with the epigraph to Chapter 4 of Astrophysical Gas Dynamics.
![The beginning of Chapter 4 ("Advanced Shocks") of Astrophysical Gas Dynamics, to be published in 2026. The epigraph of the chapter is
Captain Renault: I am shocked, *shocked*, to find that gambling is going on in here.
[Julius Epstein, Philip Epstein, and Howard Koch. Casablanca screenplay, 1942]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreibo5ev7uxwnckb3ai2kvz5wbpcsgv6qgf347zyhnuxn3qnadjwd3q@jpeg)
June 28, 2025 at 8:20 PM
I continue my cinematic era with the epigraph to Chapter 4 of Astrophysical Gas Dynamics.
I cannot guarantee that I will stop crabbing. I will try, however, to stop doing it from pontoons.
May 24, 2025 at 10:30 PM
I cannot guarantee that I will stop crabbing. I will try, however, to stop doing it from pontoons.
Given 274 confirmed moons of Saturn, Lucy definitely has a point.
March 18, 2025 at 3:36 PM
Given 274 confirmed moons of Saturn, Lucy definitely has a point.
I am entering my cinematic era with the epigraph for Chapter 3 of Astrophysical Gas Dynamics.
![epigraph for chapter 3 of Astrophysical Gas Dynamics: "In space, no one can hear you scream." [Barbara Solinger Gips, advertising tagline for Alien]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreibpy7hlfetcd3x5zj6mznvk6nygse65yhzsoamfrtwnznci5rtl7a@jpeg)
March 15, 2025 at 3:39 PM
I am entering my cinematic era with the epigraph for Chapter 3 of Astrophysical Gas Dynamics.
I have chosen an epigraph for Chapter 2, and I think I have found a good illustration for the difference between Lagrangian and Eulerian observers. (I still have to negotiate the rights from the Shepard Trust, however.)
![Epigraph for Chapter 2 of Astrophysical Gas Dynamics: "When the gap between ideal and real becomes too wide, the system breaks down" Barbara Tuchman (1912-1989) A Distant Mirror, Foreword [1978]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreibrv3zjqpo3vstoegsfd3fjo6chhpwtz4ixaz7exsoroi7xg2kgqy@jpeg)
![Figure 2.1 from Astrophysical Gas Dynamics: panel (a) show Eeyore drifting downstream, panel (b) shows Pooh, Piglet, Roo, and Rabbit watching from a bridge [illustration from The House at Pooh Corner, chapter 6, E. H. Shepard, artist]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreihm54qvteckfiozfjondhuq3bnya3s6ivaziq5jknxhiwwfqpcmuq@jpeg)
February 23, 2025 at 7:34 PM
I have chosen an epigraph for Chapter 2, and I think I have found a good illustration for the difference between Lagrangian and Eulerian observers. (I still have to negotiate the rights from the Shepard Trust, however.)
The latest volume in The Ohio State Astrophysics Series has been published! Thanks go to everyone in The Ohio State Astronomy Department, but especially to the students in the graduate dynamics class.
February 6, 2025 at 8:36 PM
The latest volume in The Ohio State Astrophysics Series has been published! Thanks go to everyone in The Ohio State Astronomy Department, but especially to the students in the graduate dynamics class.
Opposing fascism and defying gender stereotypes: it's as American as apple pie, the Saturday Evening Post, and Norman Rockwell.
![Saturday Evening Post cover, January 2, 1943: a baby (symbolizing the new year) bayonets a swastika. [J. C. Leyendecker, artist]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreiglcfr7pe3fnkbxwrkwieicfbmv4rdrjdmffsuncvp4ftdrt3wd3m@jpeg)
![Saturday Evening Post cover, May 29, 1943: Rosie the Riveter eats a sandwich on her lunch break, in front of an American flag. [Norman Rockwell, artist]](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:yzfqfs2pagb63bgij4fzummk/bafkreieceweip74zq22n3yt5vhd7vqamvhz437h2ujg2oe4lm6h2glq3hm@jpeg)
February 6, 2025 at 12:26 AM
Opposing fascism and defying gender stereotypes: it's as American as apple pie, the Saturday Evening Post, and Norman Rockwell.
When a polar vortex is on its way, it is important to be prepared.
January 18, 2025 at 4:37 PM
When a polar vortex is on its way, it is important to be prepared.
Are you attending #aas245? Stop by the Cambridge University Press display and get 30% off their featured books (including my latest, Celestial and Stellar Dynamics). Not attending? You can still get the discount online.
American Astronomical Society Winter Meeting
www.cambridge.org
January 12, 2025 at 3:11 PM
Are you attending #aas245? Stop by the Cambridge University Press display and get 30% off their featured books (including my latest, Celestial and Stellar Dynamics). Not attending? You can still get the discount online.
This is the time of year when I always think of the Ogden Nash poem "Good Riddance, But Now What?" It ends with the couplet:
Hark! It's midnight, children dear.
Duck! Here comes another year.
(I am preparing to duck 2025.)
Hark! It's midnight, children dear.
Duck! Here comes another year.
(I am preparing to duck 2025.)
December 31, 2024 at 7:30 PM
This is the time of year when I always think of the Ogden Nash poem "Good Riddance, But Now What?" It ends with the couplet:
Hark! It's midnight, children dear.
Duck! Here comes another year.
(I am preparing to duck 2025.)
Hark! It's midnight, children dear.
Duck! Here comes another year.
(I am preparing to duck 2025.)
With Christmas lunch, there is nothing like a snowman-shaped glass filled with Guinness. ("I didn't say there was nothing better. I said there was nothing like it.")
December 25, 2024 at 8:37 PM
With Christmas lunch, there is nothing like a snowman-shaped glass filled with Guinness. ("I didn't say there was nothing better. I said there was nothing like it.")
Progress! I have chosen the epigraph for the first chapter of my next book (Astrophysical Gas Dynamics, to be published in 2026).
May I have a cookie now?
May I have a cookie now?
December 24, 2024 at 5:53 PM
Progress! I have chosen the epigraph for the first chapter of my next book (Astrophysical Gas Dynamics, to be published in 2026).
May I have a cookie now?
May I have a cookie now?
Best Caturday wishes. I hope you are able to spend some time hanging out with your buddies.
December 14, 2024 at 9:24 PM
Best Caturday wishes. I hope you are able to spend some time hanging out with your buddies.
The two people on the right when the clip begins are LePrince's parents-in-law, who were both born in 1816.
Yes, there exists video footage of people born during the reign of George III.
Yes, there exists video footage of people born during the reign of George III.
What's your favorite 80's movie?
Mine is the Roundhay Garden Scene (Louis LePrince, director: October 1888)
Mine is the Roundhay Garden Scene (Louis LePrince, director: October 1888)
Roundhay Garden Scene (1888)
YouTube video by Classic Film Channel
youtu.be
December 6, 2024 at 8:48 PM
The two people on the right when the clip begins are LePrince's parents-in-law, who were both born in 1816.
Yes, there exists video footage of people born during the reign of George III.
Yes, there exists video footage of people born during the reign of George III.