Observed P Cygni
profiles in two
hot stars:
z
Pup
(O4, 10
6
L
sun
) and
t
Sco
(B0 V,
50,000 L
sun
)
Steady-state
theory is very
successful
at
explaining the
time-average
properties of
hot-star winds
O stars’ radiation-driven winds contain enormous
kinetic energy