Wind speeds on extrasolar worlds

We propose for photometric monitoring observations of 2MASS J10475385+2124234 and WISE J112254.73+255021.5 using Spitzer/IRAC. 2MASS J1047+21 and WISE J1122+25 are late spectral type (T6.5 and T6) radio emitters and have measured radio periods of 1.77 hrs and 1.30 hrs, respectively. Our proposed observations will not only characterize the variability of the two coolest known radio emitters but also provide a unique opportunity to measure the first wind speeds for brown dwarfs. Spitzer is currently the only facility capable of the photometric stability, continuous observations and 4.5 micron sensitivity necessary for the success of our program.