Measuring the ages of low‐mass stars and brown dwarfs

Age is among the most elusive, yet important, fundamental properties of low–mass stars and brown dwarfs. M dwarfs have main-sequence lifetimes that are estimated to be trillions of years, with little change in luminosity. In contrast, brown dwarfs cool and dim with time, resulting in a significant degeneracy between mass, age, and luminosity. Despite these inherent challenges, there have been recent efforts on both observational and theoretical fronts that may yield precise ages for low-mass stars and brown dwarfs. We feature some current observational efforts focused on estimating ages of these objects as presented in our Cool Stars 17 splinter session. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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