Birth of a galaxy

THANKS to the Bubble Space
Telescope, scientists can now actually see ancient galaxies being forI
The instrument, unlike earthbound
telescopes, can be aimed at galaxies 4 billion light years away. Because
le the light that is picked up was emitted 4 billion years ago, it provides a
view of the galaxy as it was then.

Astronomers at USA's Carnegie
Institution recently saw a galaxy
cluster that was formed about 5 billion years ago, a third of the way
back to the Big Bang, one of the theories used by scientists to explain the
tic birth of the universe. According to
the Big Bang theory, the universe
evolved about 15 billion years ago
Though the cluster contains galaxies
that are seen today as elliptical, lens
shaped and gardens of spirals
astronomers report their proportions
were quite different in the past
(Science, Vol 258, No 5089). Some 30
per cent of the galaxies were spiral
in then, whereas now such galaxies in
modern galactic clusters are only 5
per cent.

Scientists postulate spiral galaxies are active star farmers, which
burn out after using up all their star
forming material.