Travis Metcalfe

Ratio of the observationally estimated and model wind braking torque as a function of Rossby number normalized to the solar value. The dotted line and gray shaded region illustrates the fit and 95% confidence interval described by Metcalfe+2025b. The revived magnetic braking in 31 Aql at higher Ro is evident, and quadratic growth is illustrated schematically with a dashed line.

SNEAK PREVIEW: after the collapse of the global dynamo stalls main-sequence spin-down for billions of years, physical expansion on the subgiant branch finally allows stars to reach the transition to anti-solar DR (~1.1 Ro_crit), restoring the large-scale field and reviving magnetic braking!

Title slide for a presentation at #AAS247

It took 10 years to trace Weakened Magnetic Braking back to it's root cause (the collapse of the global stellar dynamo), but next week at #AAS247 you can hear me explain how we did it in less than 10 minutes! Thursday, January 8th at 10:10am in room 222C. submissions.mirasmart.com/AAS247/Itine...

"Nature is so rich you are unlikely to look carefully at anything without learning something new, particularly in unexplored territory... do something nobody thinks is interesting. Trust me: it will be." ~Ed Nather whitedwarf.org/education/ad...

Zen Santa levitating over the slogan "This year, rise above it"

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a close up of a feather on a rock with the words `` hello '' written in white letters . Alt: a close up of a feather on a rock with the words `` hello '' written in white letters .

I recently moved over from X, but I have only found a small fraction of the astronomers I followed over there (and almost nobody has found me here yet). #stellarastro #exoplanet

The Sun’s magnetic midlife crisis Old Sun-like stars observed by the Kepler Space Telescope spin faster than astronomers expected. Apparently, they experience a dramatic shift in their rotation and magnetism at about middle age.

When I wrote this "Quick Study" on Weakened Magnetic Braking for @physicstoday.bsky.social in 2018, we already had the physical picture largely correct – we just didn't have all of the evidence in hand to support it. Now we do. physicstoday.aip.org/quick-study/...

Activity cycles grow longer and weaker as stars become less active over time. [Data from Isaacson+ 2024, 2025].

I'll be visiting New Mexico later this week, giving an astronomy colloquium about what happens to stellar dynamos toward the end of main-sequence lifetimes. astro.nmsu.edu/events/collo...

I'm not an attorney, but from what I understand the relevant legal difference is between changing the rules on existing contracts versus updating the rules for future contracts.

Looking forward to giving the LASP seminar this afternoon, 1:00pm in SPSC-N100 and on zoom (preview of an astronomy colloquium next week at NMSU). lasp.colorado.edu?science-semi...