|
⇤ ← Revision 1 as of 2026-01-03 08:37:31
Size: 1655
Comment:
|
Size: 1670
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 24: | Line 24: |
| . Perhaps 3e12 comets per star times 1e24 stars is 6e36 icy bodies in the universe, not counting | . Perhaps 3e12 comets per star times 1e24 stars is 6e36 icy bodies in the universe, not counting unbound bodies |
Steven Austad Books
https://www.uab.edu/cas/biology/people/faculty/steven-n-austad
- The University of Alabama at Birmingham
- College of Arts and Sciences, Department of Biology
Methuselah's Zoo
what nature can teach us about living longer, healthier lives
- 2022 Beaverton Lib 571.879 AUS
- p111 "Biology is complicated. If it were simple, it would be physics"
---
How many atoms in human body?
- Total Earth biomass 550 GT carbon 5.5 x 1e2 x 1e9 x 1e6 (tonnes per gram) = 5.5e17 grams
- carbon is 12 amu and 12% of the atoms in human body
- Avogadro's number 6e23, hence one gram of human carbon is 5e22 atoms
- Associated with (100/12)*5e22 ≈ 4e21 total atoms per gram of human carbon
Fermi estimate: Total Earth biomass 5.5e17 * 4e21 atoms = 2e39 biomass atoms if humans representative
- There are 1e22 to 1e24 stars in the universe
- Thousands of asteroids and trillions of comets and icy bodies orbit the Sun
- Perhaps 3e12 comets per star times 1e24 stars is 6e36 icy bodies in the universe, not counting unbound bodies
- that's a LOT of physics
- Both biology and physics are complicated ... or simple, if one is a simpleton
---
To Err Is Human, To Admit It Is Not and Other Essays
- 2022
Real People Don't Own Monkeys
- 2022
Why We Age: What Science Is Discovering about the Body's Journey Through Life
1999 Why We Age: What Science Is Discovering about the Body's Journey Through Life