  Atomic nuclei are transformed into each other in the cosmos by nuclear
reactions inside stars: -- the process of nucleosynthesis. The basic concepts
of determining nuclear reaction rates inside stars and how they manage to burn
their fuel so slowly most of the time are discussed. Thermonuclear reactions
involving protons in the hydrostatic burning of hydrogen in stars are discussed
first. This is followed by triple alpha reactions in the helium burning stage
and the issues of survival of carbon and oxygen in red giant stars connected
with nuclear structure of oxygen and neon. Advanced stages of nuclear burning
in quiescent reactions involving carbon, neon, oxygen and silicon are
discussed. The role of neutron induced reactions in nucleosynthesis beyond iron
is discussed briefly, as also the experimental detection of neutrinos from SN
1987A which confirmed broadly the ideas concerning gravitational collapse
leading to a supernova.
