Walkabout the Galaxy
exomoons, fast blue optical transients, Mars' core
Astrophysics and Astronomy | Physics
They have to be out there, and now we have a first direct glimpse of what is likely to be the birthplace of an exomoon - a moon forming in a disk around a planet orbiting another star. We check in on the curious case of FBOTs (fast blue optical transients), and closer to home we've learned that Mars' interior has a bigger core than anticipated. Get this news, space news, trivia linking sci-fi and planetary-sci, and much more.
The Killing Field
If your manifold metric is leaky, and you're in the market for a new vector field, then the killing field may be just what you need. With a vanishing Lei derivative of the metric respect to the field, the killing field makes sure your flow generates a symmetry, and makes sure the distances are not distorted in the direction of the killing vector. Known for "the little group" of generators of rotations and the boost generators in the Minkowski space, Wilhelm Killing's killing field will give you a twist and a boost in a metric-preserving way. The killing field, don't be evil (Google).
@ Joshua Colwell, All Rights Reserved
Length of Episode
Colwell, Joshua; Dove, Adrienne; and Cooney, James, "Exomoons and Inside Mars" (2021). Walkabout the Galaxy Podcast. 170.