Geomorphology and Pi

May 20, 2010 at 6:02 pm · Filed under Really Cool Science

I learned something cool from the book I’m readingright now.

I did not know this, but apparently there is a reasonably consistent ratio between the length of rivers from source to mouth, and their direct length as the crow flies.

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Nerds of the World, Unite

November 22, 2009 at 6:09 pm · Filed under Great Minds, Really Cool Science, Videos

Jim Kakalios was a science advisor for the Watchmen movie, and wrote a book called The Physics of Superheroes. He gave this very entertaining and edifying 2009 convocation address at the University of Minnesota, and talks about geeks and nerds. And how we run the world.

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We Are All Made of Star Stuff

December 26, 2008 at 8:46 am · Filed under Astronomy, Really Cool Science

A brief primer on the history behind this:
- The Big Bang happened.
- This produced Lithium, Helium and Hydrogen.
- Some of this Lithium, Helium and Hydrogen coalesced into stars.
- The very high pressures and resulting hot temperatures inside stars converted some of the lithium, helium and hydrogen into heavier elements in a process called nucleosynthesis. This is essentially what the old alchemists on our planet were trying to do, but as far as we know, this can only happen inside stars, because of the high pressure needed. Got any gold around? Take a look at it. As the core collapsed in a dying star, a gravity wave collapsed inward with it. In that moment, as a star died, that gold was formed.
- The stars spewed out these new elements into the universe (and continue to do so)
- Some of these elements formed planets and other bodies (and continue to do so)

Thats the story so far. Then, between four and five billion years ago, a new planet formed, orbiting a yellow dwarf star on the edge of the Orion arm of a spiral galaxy called the Milky Way. Earth.

The chemical and physical properties of Earth’s primitive environment were conducive to the origin of life. Elements combined to form more complex substances such as water, carbon dioxide, methane and hydrogen cyanide. These in turn formed key molecules such as sugars, amino acids and nucleotides. Such molecules are the building blocks of proteins and nucleic acids, compounds ubiquitous to all living organisms. Life began. A critical early triumph was the development of RNA and DNA molecules, which directed biological processes and preserved life’s “operating instructions” for future generations.

Most of life’s history on Earth has involved single celled micro-organisms. These gradually evolved into more complex cells, and about 550 million years ago, plants and animals familiar to us appeared. These too, evolved into the people and creatures we see around us today.

To give you a better idea of what exactly it is we’re made of, take a look at the elemental composition of the human body.

At some level, it seems counterintuitive to think that we’re made of star stuff. I mean, we do see the people, animals and plants around us growing all the time. To ‘get’ this,, its important to look at the really big picture. That, and as far as I can understand, remember that no new matter can be created, its just converted from one form to another.

Now, I don’t mean this in a Deepak Chopraesque, new-age, “we are one with nature” kind of way. I mean literally. We are particles of stardust that have attained consciousness, for a brief period. Dust to dust and all that. What does this mean for us? For humanity? I don’t know. Depends on your worldview, perhaps I’ll explore this question in another post someday. However, its nice to know. I like this creation story a lot better than the older, more established ones.

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