Burn modifiers for MESA-Web Aug 13 2024, 21:05

Inspired by a feature request from Mathieu Renzo, I've updated MESA-Web to add 'burn modifiers'. These allow users to disable the energy release and/or the chemical evolution arising from thermonuclear burning reactions.

Here is a MESA-Web movie illustrating the evolution of a solar-mass/composition star, with both energy release and chemical evolution disabled. It's a great illustration of what would happen if the Sun was prevented from burning: after a period of Kelvin-Helmholtz contraction, it would become a (mostly) hydrogen white dwarf, gradually radiating away its remaining thermal energy.

I created a torque limiter Aug 4 2024, 00:17

I recently upgraded my venerable Ender 3 v2 3-D printer to a Bambu Lab A1, and I'm blown away by the increase in print speed, quality and reliability. One of the first things I've fabricated using the A1 is a torque limiter for a motor-drive assembly (the motivation is that a buddy of mine is making a Halloween costume for his son, and we want to make sure that motor-driven parts don't end up hurting fingers!).

I designed the torque limiter using Fusion 360 (free for personal use!), and assembled it with ~ $10 worth of off-the-shelf components. I'm pretty pleased with the result, and have uploaded the design to Thingiverse.

GYRE 7.1 released Aug 31 2023, 15:09

A few weeks ago, I released version 7.1 of the GYRE stellar oscillation code. This version adds support for turbulent viscous damping in convection zones, and is the second major release in 2023 (version 7.0 brought the ability to model tidally forced oscillations; see Sun, Townsend & Guo 2023 for details). It also fixes a bug in the evaluation of weight functions, which was reported in a recent research note (Townsend & Kawaler 2023).

Two Cultures, #1 Aug 31 2023, 14:46

In the USA, when the Queen song "We Will Rock You" is played on the radio, it is always followed by "We Are the Champions".

This never happens in the UK.

MSG 1.3 released Jul 31 2023, 15:15

Earlier this month, I released version 1.3 of the MSG software package. MSG (short for Multidimensional Spectral Grids) synthesizes astrophysical spectra and photometric colors via interpolation in pre-calculated grids. Given a set of stellar atmospheric parameters (e.g., effective temperature, gravity and metallicity), MSG can calculate the specific intensity of the emergent radiation field as a function of wavelength and angle. It can also convolve these data with appropriate filters and response functions, to evaluate colors in a wide variety of photometric systems. A brief summary of the package can be found in Townsend & Lopez (2023), and full documentation at the link above.