  Despite a century of remarkable progress in understanding stellar interiors,
we know surprisingly little about the inner workings of stars spinning near
their critical limit. New interferometric imaging of these so-called ``rapid
rotators'' combined with breakthroughs in asteroseismology promise to lift this
veil and probe the strongly latitude-dependent photospheric characteristics and
even reveal the internal angular momentum distribution of these luminous
objects. Here, we report the first high precision photometry on the
low-amplitude delta cuti variable star Rasalhague (alpha Oph, A5IV, 2.18 Msun,
omega/omega_c~0.88) based on 30 continuous days of monitoring using the MOST
satellite. We have identified 57+/-1 distinct pulsation modes above a
stochastic granulation spectrum with a cutoff of ~26 cycles per day.
Remarkably, we have also discovered that the fast rotation period of 14.5~hours
modulates low-frequency modes (1-10 day periods) that we identify as a rich
family of g-modes (|m| up to 7). The spacing of the g-modes is surprisingly
linear considering Coriolis forces are expected to strongly distort the mode
spectrum, suggesting we are seeing prograde ``equatorial Kelvin'' waves (modes
l=m). We emphasize the unique aspects of Rasalhague motivating future detailed
asteroseismic modeling -- a source with a precisely measured parallax distance,
photospheric oblateness, latitude temperature structure, and whose low-mass
companion provides an astrometric orbit for precise mass determinations.
