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Tuesday, March 06, 2012

We Are Stardust

Helena Curtis was an amazing writer. She's famous for her introductory biology textbook published by Worth beginning in 1968 [Good Science Writers: Helena Curtis]. Here's the opening paragraphs.
Our universe began, according to current theory, with an explosion that filled all space, with every particle of matter hurled away from every other particle. The temperature at the time of the explosion—some 10 to 20 billion years ago—was about 100,000000000 degrees Celsius (1011 °C). At this temperature, not even atoms could hold together; all matter was in the form of subatomic, elementary particles. Moving at enormous velocities, even those particles had fleeting lives. Colliding with great force, they annihilated one another, creating new particles and releasing great energy.

As the universe cooled, two types of stable particles, previously present only in relatively small amounts, began to assemble. (By this time, several hundred thousand years after the "big bang" is believed to have taken place, the temperature had dropped to a mere 2500°C, about the temperature of white-hot wire in an incandescent light bulb.) These particles—protons and neutrons—are very heavy as subatomic particles go. Held together by forces that are still incompletely understood, they formed the central cores, or nuclei, of atoms. These nuclei, with their positively charged protons, attracted small, light, negatively charged particles—electrons—which moved rapidly around them. Thus, atoms came into being.

It is from these atoms—blown apart, formed, and re-formed over the course of several billion years—that all the stars and planets of our universe are formed, including our particular star and planet. And it is from the atoms present on this planet that living systems assembled themselves and evolved. Each atom in our own bodies had its origin in that enormous explosion 10 to 20 billion years ago. You and I are flesh and blood, but we are also stardust.
Neil DeGrasse Tyson tops that in his spontaneous answer to the question, "What is the most astounding fact you can share with us about the Universe?"

If you're going to sing "we are stardust" then you can't do it any better than this group. The song was written by Joni Mitchell (another Canadian) but her version is not as good.

[Hat Tip: Phil Plait of Bad Astronomy: Neil Tyson’s most astounding fact.]


  1. Maybe the reason CSNY does a better version of this song about Woodstock than Joni is because they, unlike Joni, actually went to Woodstock.

  2. Our universe began, according to current theory, with an explosion that filled all space, with every particle of matter hurled away from every other particle.

    Sigh. It didn't fill space--space was generated with it. There was no space into which the universe expanded. A minor quibble, I suppose, but otherwise--a nice paragraph.

  3. I object to the opening sentence: "Our universe began". This is an assumption. What we know for sure happened at the big bang is that the universe took on dimensionality (began to expand), making the expression of some of its contents as matter possible. We don't know that it actually came into existence at that point, and I'm not aware of any fact that necessitates that it did, rather than simply changing state. In a practical sense, our universe AS WE KNOW AND EXPERIENCE IT TODAY effectively began at that point, but I don't like the absolute way it's stated here because it automatically throws a bone to creationists.

  4. I have a copy of her "Biology" (4th Edition) on my bookshelf