Edwin Powell Hubble

It's a Fact 
When he died , Hubble's wife, Grace, did not have a funeral for him and never revealed what was done with his body it was apparently Hubble's wish to have no funeral service and be buried in an unmarked grave, or that he wanted to be cremated. As of now, the whereabouts of his remains are unknown.

Edwin Powell Hubble
```````````(1889 -1953) 
~~~~~~~~~~~The "Galactic" astronomer 

Born : November 20, 1889 Marshfield, Missouri, U.S. 
Died : September 28, 1953 (aged 63) San Marino, California 
Residence : U.S. Nationality: American 
Field : Astronomy 
Institutions : University of Chicago 
Mount Wilson : Observatory 
Alma mater : University of Chicago Orford University 
Known for : Big Bang, Hubbies taw Redshift, Hubble sequence


Edwin Hubble forever changed our view of the Universe. In 1929 he showed that galaxies are moving away from us with a speed proportional to their distance, and showed that the Universe is expanding. 

During the early years of 20th century people thought Milky Way was the only galaxy. But by 1920's an astronomer of American birth disproved this by discovering more galaxies or what Immanuel Kant named "Island Universes" . He is none other than Edwin Hubble. Edwin Hubble thus founded the study of the Universe and gave a new dimension to the study of cosmology, the scientific study of the Universe as a whole. He discovered some 'nebulae', later realized to be galaxies, were outside our galaxy. 

He classified galaxies according to their shape as elliptical (designated E), spiral (5), and irregular (Ir). He later calculated their real velocities and by doing this he put forward the idea of 'expanding Universe', a name coined by British astronomer Sir Arthur Stanley Eddington in 1933. However the phenomenon might be also be called mutual recession of galaxies.(This phenomenon was also discovered by Vesta Stipher, but Hubble's discovery is better known.)

Hubble was born in the Midwest and moved with his family to Chicago Illinois in 1898 where he attended high school. He was an above average student though not the most exceptional. He was more promising as an athlete breaking the Illinois state high jump record. At University he was an accomplished basketball player, playing for University of Chicago. He later won a Rhodes scholarship to Oxford where he studied law. After returning to USA he decided to study astronomy.

In the early 1920's Hubble did lot of research in establishing just what galaxies are. It was known that some spiral nebulae i.e. fuzzy clouds of light in the night sky, contained individual stars. But there was no agreement as to whether these were relatively small collections of stars within our own galaxy, the Milky Way that stretches right across the sky or whether these could be separate galaxies or 'Island Universes'. In other words Hubble in 1924 proved that ours is not the only galaxy, and later worked out the distances to nine different galaxies.

In 1924 Hubble measured the distance to the Andromeda nebula, and showed that it was about a 100 thousand times as distant as nearest stars. He postulated that it had to be a different galaxy, comparable in size to our own Milky Way but much further away. Thus Hubble is credited with "discovering" Andromeda galaxy. 

Hubble was able to measure the distances to only a handful of other galaxies as mentioned above and used as a rough guide , apparent brightness of galaxies as an indication of their distance. The speed with which a galaxy was moving toward or away from us was relatively easy to measure due to the Doppler shift of red light. Just as a sound of an ambulance becomes lower as it speeds away fryom us, so the light from a galaxy becomes redder and red shifted as it recedes. Though our ears can hear the change of pitch of the ambula1ance, our eyes cannot detect the very small redshift of light, but using a sensitive spectrograph Hubble was able to determine the redshift of light from distant galaxies. 

Hubble later found out that this redshift of moving galaxies was proportional to the distance. i.e. distant galaxies are moving with faster velocity. This relationship of recession velocity of galaxies increasing with distance was called Hubble's relation. The proportionality introduced to this relation was called Hubble's constant and is known as H. This observational evidence vindicated the theoretical physics research done by Einstein, which was published in 1915, namely General theory of Relativity and later research by Alexander Friedmann in Russia. These investigations paved the way for modern cosmology and the theory of the Big Bang. 

Posted in: Greatest Astronomers