We study the stability of a Bose condensate of atomic Li-7 in a (harmo
nic oscillator) magnetic trap at nonzero temperatures. In analogy to t
he stability criterion for a neutron star, we conjecture that the gas
becomes unstable if the free energy as a function of the central densi
ty of the cloud has a local extremum which conserves the number of par
ticles. Moreover, we show that the number of condensate particles at t
he point of instability decreases with increasing temperature, and tha
t for the temperature interval considered, the normal part of the gas
is stable against density fluctuations at this point.