We have used the Spitzer Space Telescope InfraRed Spectrograph (IRS) 22-mm peakup array to observe thermal emission from the nucleus and trail of comet 103P/Hartley 2, the target of NASA’s Deep Impact Extended Investigation (DIXI). The comet was observed on UT 2008 August 12 and 13, while the comet was 5.5 AU from the Sun. We obtained two 200-frame sets of photometric imaging over a 2.7-hour period. The comet showed extended emission beyond a point source in the form of a faint trail directed along the comet’s anti-velocity vector. Assuming a NEATM model for the nuclear emission with beaming parameter of 0.95±0.20, the effective radius of the nucleus is 0.57 ± 0.08 km. With this nucleus size and a water production rate of 3 x 10²⁸ molecules s^-1 at perihelion (A’Hearn et al. 1995) we estimate that ~100% of the surface area is actively emitting volatile material at perihelion. Compared to Deep Impact’s first target, comet 9P/Tempel 1, Hartley 2’s nucleus is one-fifth as wide (and so about one-hundredth the mass) while producing a similar amount of outgassing at perihelion with about 13 times the active surface fraction. Unlike Tempel 1, it should be highly susceptible to jet driven spin-up torques, and so could be rotating at a much higher frequency. Since the amplitude of non-gravitational forces are surprisingly similar for both comets, close to the ensemble average for the short period comets (Yeomans et al. 2004), we conclude that comet Hartley 2 must have a much more isotropic pattern of time averaged outgassing from its nuclear surface. Barring a catastrophic breakup or major fragmentation event, the comet should be able to survive up to another 100 apparitions (~700 yrs) at the current rate of mass loss.