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Old April 10th 06, 04:03 AM posted to uk.sci.astronomy
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Default Proportion of stars in our galaxy question

Boo wrote in
:

Hi,

I am curious to know what proportion of the points of light that are
visible to the naked eye are part of our galaxy ?


All except one. The core of M31 is naked eye visible as a point of
light.

The Magellanic Clouds don't look like points of light, and everything
else is too far away.


Well, I'm astonished to discover that ! So, before the telescope all
the known universe was just our own galaxy and Andromeda ?


Even with the discovery of the telescope, the concept of galaxies was not
known for a few centuries. While many "nebula" were catalogued, it was not
realised that some of them were actually external to the "milky way". There
was some argument about this until Edwin Hubble succeeded in resolving
individual Cepheid variable stars in M31 and was thus able to determine that
its' distance was too great to be a part of the Milky Way. This was in the
1920's so not really all that long ago. By the way, the Magellanic Clouds are
external to the Milky Way andt are easily visible to the unaided eye. As
another poster said, they don't look like stars. The exception to this was
back in 1987 when there was a supernova in the Large MC which was easily
naked eye visible a month or two.

Klazmon.