Assignments: Class #3

Resources for individual classes

Before the 3rd class,

• Please read the following stories in The Complete Cosmicomics:

-- Without Colors

-- Games Without End

• Please watch or read these materials:

From Without Colors: “Before forming its atmosphere and its oceans, the Earth must have resembled a grey ball revolving in space. As the Moon does now; where the ultraviolet rays radiated by the Sun arrive directly, all colours are destroyed, which is why the cliffs of the lunar surface, instead of being coloured like Earth’s, are of a dead, uniform grey. If the Earth displays a varicoloured countenance, it is thanks to the atmosphere, which filters that murderous light.”

After reading Without Colors, use the following resources to think about what color is, and how the "murderous" light from the sun destroys color.

Click HERE to go to How Scientists Know Molecules in a new window.

Watch the following videos from this page:

• What is a Molecule?
• Types of Molecular Spectroscopy
• Protein Crystal Diffraction, and
• The 2017 Nobel Prize in Chemistry: Cryoelectron Microscopy

How Scientists Know About... is a website I created for use in various courses I have taught at OLLI. Look over the menu at any one of its pages to see if any of those subjects interest you.

By the way, if the subject of color appeals to you, take a look at this book: Blue: The Science and Secrets of Nature's Rarest Color.

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After reading Games Without End

From Games Without End: “When the galaxies become more remote, the rarefaction of the universe is compensated for by the formation of further galaxies composed of newly created matter. To maintain a stable median density of the universe it is sufficient to create a hydrogen atom every two hundred and fifty million years for forty cubic centimetres of expanding space. (This steady-state theory, as it is known, has been opposed to the other hypothesis, that the universe was born at a precise moment as the result of a gigantic explosion.)” (Note from Gale: emphasis mine.)

Here is a cube with a volume of about 40 cubic centimeters:

The prelude (above) to Games Without End got me thinking about how empty the space in our universe really is. To keep the density of the universe constant despite its expansion, all that's required is for one atom to appear in every cube of the size shown in the picture just once in every two hundred million years. This theory, called "steady-state" theory, was a competitor to big bang theory until the discovery of the cosmic microwave background radiation (CMBR) in 1965. This discovery exposed a relict (or is it relic?) of the universe's past that steady-state theory could not explain, and thus made steady-state theory much less tenable. 

When you have several theories, plus a new discovery that only one of them can explain, the others fall aside, or are put on the back burner. 

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