Milky Way. Computer artwork of our galaxy, the Milky Way, seen obliquely from above. This image is based on measurements of the galaxy's stars taken in infrared, radio and other wavelengths. Many of these stars are obscured in visible wavelengths by gas and dust clouds. The position of our Sun is shown by the bright yellow dot (lower centre), about halfway out from the nucleus (yellow) in one of the spiral arms (blue). The colours seen here are due to the old, yellow stars of the nucleus and the hot blue light of the new stars forming in the arms. The Milky Way is thought to be around 120,000 light years wide, and to contain some 100 billion stars.