• Astronomers Measure Wind Speed on a Brown Dwarf (NRAO)
• Center for Astrophysics Scientist and Team First to Measure Wind Speed on an Object Outside the Solar System (Harvard)
• Allers Develops New Technique to Measure Wind Speed Outside Solar System (Bucknell)

In our final story of the day, we’d like to note that a team of researchers has taken lessons learned from studying Jupiter and Saturn, and applied those lessons to studying a nearby brown dwarf star. Specifically, planetary scientists had realized that if they use radio telescopes to measure the rotation of the core of a planet they saw a different rotation rate than they saw at the surface of the world. The difference in these two rates had to go somewhere, and this case the energy was lost to the wind – literally it was lost to planetary outflows. Thanks to spacecraft at Jupiter and Saturn it was possible to physically measure these winds and check all the relationships. This relationship between inner and outer rotation rates and wind can be expressed in straight-forward equations that should be applicable to all similarly structured objects. 

And here is where one day astronomer Katelyn Allers had the realization that brown dwarfs count as similarly structured objects. And she realized no one had published on this application before. Allers and her team used data from the Spitzer Space Telescope and VLA to study the nearby brown dwarf 2MASS J1047+21, which is only 34 light years away. These two sets of data allowed them to measure the dwarf to be rotating once every 1.758 days in the interior, and once every 1.741 hours in the atmosphere. This difference resulted in a wind of 650 m/s. This rate matched predictions on how wind speeds should change as objects gain mass from Saturn, to Jupiter, to these 40 Jupiter mass failed-starts. This is a cool piece of science, and it shows that we really need more interdisciplinary thinking, with astronomers and planetary scientists, as well as geologists, all taking time now and then to learn from one another.