Sunday, April 12, 2009

WYSIWYG - Edwin Hubble

Edwin Hubble (1889-1953)

The huge piece of ground glass had been transported to the top of Mount Wilson and carefully placed on a huge balanced frame to collect light from the stars seen on the night sky of California.

But all that feat of engineering would be of no use unless someone knew how to use it for something meaningful. The 100 inch Hooker was now the largest telescope humanity had ever built - but so what. A star is a star, eh?

At that time, in the beginning of the 20th century, space was a rather boring place. Astronomers estimated that the entire universe is about 100.000 light years in diameter and filled with stars that are essentially similar to our sun, some bigger some smaller. Probably there are millions of stars and many of them have planets like our sun but they are too small to be seen directly. Huge distances separate these stars from each other as they follow their movements according to the static laws of physics for gravity established by Sir Isaac Newton.

Between the stars 19th and early 20th century scientists observed smaller objects, comets and asteroids and clouds of dust. Everything out there is freezing cold and the entire cosmos is eternal. It has no beginning and no end.

Theologians and Biblical scholars were not particularly interested or impressed by the astronomy of the time and there are no huge quarrels about an eternal universe although the Bible says otherwise. Those Christians and Jews who were talking about natural sciences were discussing Charles Darwin and Sir George Lyell as they were subjects closer to home.

They did not realize that space is the ultimate front for the battle between faith in God and materialistic atheism that dwarfs those discussions about evolution or catastrophic floods. Nothing much has changed in this respect.


So the telescope was up there thanks to the generosity and far-sightedness of John Hooker and the enthusiasm and skills of the astronomer George Ellery Hale. It was a great achievement for human engineering skills and a masterful design but it would be basically just a dead piece of glass and metal without someone who would know how to use it.

Hubble with his beloved pipe
Mount Wilson Observatory

Enter the King of the Hill. Edwin Hubble had arrived to Mount Wilson 1919 and Hooker had its days of glory that were soon to entirely change human perception of the universe.

Wikipedia tells nicely about his youth:

Edwin Hubble was born to an insurance executive in Marshfield, Missouri, and moved to Wheaton, Illinois, in 1889. In his younger days he was noted more for his athletic prowess than his intellectual abilities, although he did earn good grades in every subject except for spelling. He won seven first places and a third place in a single high school track & field meet in 1906. That year he also set the state high school record for the high jump in Illinois. Another of his personal interests was dry-fly fishing, and he practiced amateur boxing as well.

I think this interest in athletics was excellent preparation for those long cold winter nights on Mount Wilson when he could not get his mind and eyes off the bright canopy of stars opening above him and the amazing massive telescope he was using with such determination and skill. A round or two around the observatory would warm up those toes as the glass mirror had to be in stable temperature and too much heating could disturb the air and clarity of vision.

Edwin Hubble at work

Hooker telescope saw light on November 2, 1917 and Edwin Hubble began using it in 1919. The biggest eye humanity had ever opened towards the deep space with a massive 2.5 meter mirror collecting very faint rays of light.

But Edwin had not only the best telescope of his time at use. He also had in his pocket something very important that Henrietta Swan Leavitt had understood in the Harvard observatory as a human "computer" looking at photos of the night sky. Henrietta had shown how the Cepheid stars are "blinking" in a standard and measurable way. The variations in their brightness are like Roman milestones in the space and help in determining distances.

Hubble had a view of the space nobody else who did not have access to Hooker had. We cannot blame earlier astronomers for assuming that those hazy clouds, nebulae, they barely saw was for them interstellar dust. They did not see clear enough. Similarly, we cannot blame that Galileo was thinking Saturn has "horns" - that is how the rings looked through his primitive self-made telescope.

Through Hooker the King of the Hill observed in much greater details the structures of the nebulae and eventually he classified these clouds by their shape in his famous "tuning iron" of galaxies.

Hubble's "tuning" iron classifies and groups galaxies by basic shape

On October 5, 1923 Edwin Hubble was looking through Hooker at a cloud on the sky in the constellation of Andromeda and noticed a Cepheid variable star in it.

This very accurate and careful observation made after three years of patient observation of deep sky gave Hubble an idea about the distance. As said above, the scientific community of his time assumed that the universe is about 100.000 light years in diameter and consists mostly of stars and solar systems, mixed with some flying stones and plenty of dust.

As explained in the University of Oregon web page Cepheid stars can be used to measure distances in the space. Hubble understood that Andromeda nebula is much further away than the entire universe assumed at his time and it was not just a cloud of dust - the fine optics of Hooker clearly revealed its fine spiral structure.

The stunning news reached the world from the combination of the patient and truthful and hard work of Henrietta and Edwin - and all those who made it possible for them to work at Harvard and Mount Wilson - that we are inhabitants of a galaxy, Milky Way, and there are many more galaxies like ours out there.

Galaxies in the Local group

Today on the basis of much additional research on the footsteps of Edwin Hubble and Henrietta Swan Leavitt we know that the distance to Andromeda is 2.5 million light years and that this is the largest galaxy in the Local Group that includes our own Milky Way, the Small and Large Magellanian cloud and more than thirty other small galaxies orbiting the two big ones.

How to put it mildly?

The King of the Hill blew into pieces the scientific view of cosmos prevalent at his times.

Not everyone took it nicely.

This revolutionary achievement of Hubble could be more than enough for most people. But he made yet another, perhaps even more fundamental discovery, that has much importance also to space theology.

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