a star balance the thermonuclear power generated in its core. This requires sufficient mass. The surface losses of a less-massive brown dwarf are not fully compensated by thermonuclear burning and it cools inexoribly after formation over a Hubble time. Nevertheless, brown dwarfs constitute the low-mass, low-temperature extension of the stellar family and are an important subject in their own right[@bur.rmp; @Burrows97]. Masses in the range of $\sim$10 to $\sim$75 are frequently discussed, but overlap with the mass distribution of the EGP family is entirely possible.

Spectral Features of EGPs {#spectra}
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In principle, as with stellar atmospheres, direct detection of the spectrum of an extrasolar giant planet can reveal its elemental composition, radius, gravity (G/$^2$), and . Furthermore, when a cloud dwells in its atmosphere, its associated absorption and scattering properties might be used to determine the cloud’s particle size and makeup. Moreover, short-term temporal variations of the planet’s flux and spectrum might indicate rotation and/or meteorology. Finally, irradiation introduces the star-planet-Earth angle as an important parameter, so the orbit’s orientation and instantaneous orbital phase must be factored in (§\[phase\]). Along with the dependences on , age, stellar type, and orbital distance, this variety of influences and parameters makes the 