Many fascinating facts and insights about the universe, the earth, and life. Very well written.
p. 38 "the heavier elements were formed in supernova explosions."
p. 53 If you measured the deflection of a plumb bob from a mountain whose mass you could find the universal gravitational constant G and the mass of the earth.
p.56 Use the transit of Venus to calculate the distance of the earth from the sun.
p. 104 Avogadro's principle is that equal volumes of gas at same pressure and temperature will contain identical number of molecules, This can be used to find the diameter of a typical atom.
p. 109 Radioactive decay could account for most of earth's warmth. Radioactive elements decayed into other elements.
p. 110 It takes the same amount of time for half a radioactive sample to decay. This can be used to work out the age of a substance.
p. 122 Einstein showed that mass converts to energy very efficiently. Lots of energy in a little mass.
p. 129 In 1919 Hubble only knew of one galaxy, the Milky Way. Now there may be 140 billion galaxies.
p. 130 Pulsating stars can be used to determine relative distances.
p. 133 At 32 degrees F and sea level a sugar cube size of air will contain 45 billion billion molecules.
p. 134 An atom is the the width of a millimeter line as the thickness of a sheet of paper is to the Empire State building.
p. 141 Atoms are mostly empty space.
p. 143 THe neutron was discovered in 1932. Had it been in the 1920s the Germans might have developed the atom bomb.
p. 146 In 1997 physicists sent photons seven miles in opposite directions and interfering with one instantly changed the other.
p. 147 The weak nuclear force is 10 billion billion billion times stronger than gravity. The strong nuclear force only reaches about 1/100,000 of the diameter of an atom which is why big atoms are unstable.
p. 157 Using radioactive decay the age of the earth was estimated at 4,55 billion years.
p. 158 Before 1923 and tetraethyl lead ice cores showed no lead in the air, but since it had climbed steadily.
p. 176 1944, the continental drift theory
p. 181 Earth's surface is made of of eight to twelve big plates and about 20 smaller ones.
p. 182 The current configuration of the earth is very recent.
p. 194 Two thousand asteroids big enough to imperil civilization cross our orbit. Many more smaller ones too.
p. 205 Yellowstone is a huge cauldron of magma which erupts every 600,000 years or so.
p. 210 The earth has a core
p. 216 0-25mi crust, 25-250 mi upper mantle, 250-400 mi transition, 400-1700 lower mantle, 1700-1900 D layer, 1900-3200 outer core, 3200-3967 inner core.
p. 297 cyanobacteria, blue-green algae, absorbed water, ate the hydrogen and released the oxygen inventing photosynthesis.
p. 298 about 3.5 billion years ago cyanobacteria became tacky and formed stromatolites with three billion organisms on a square yard of rock.
p. 300 It took 2 billion years for oxygen to reach modern levels. Cells with nuclei arose. Captive bacteria, mitochondria, made complex life possible. They manipulate oxygen to liberate energy. The new cell type is called eukaryote. Old type called prokaryote.
p. 302 One trillion bacteria on your flesh.
p. 303 Every human 10 quadrillion cells, but 100 quadrillion bacterial cells.
Microbes supply the greater part of the breathable oxygen.
p. 304 A single bacteria could generate 280,00 billion individuals in a single day.
Bacteria share information, taking genetic code form each other.
p. 311 MOst of life's variety is small, unicellular, and unfamiliar. Microbes account for at least 80% of life.
p.312 One microbe in a thousand is harmful to humans.
p. 316 Many viruses have 10 genes or less. Even the simplest bacteria have several thousand.
p. 327 The Burgess shale showed lots of diversity, strange stuff that didn't make it. Evolutionary success is a lottery.
p. 328. Start evolution over and the chance of anything like human intelligence is vanishingly small.
p. 342 99.99% of all species that have ever lived are extinct. For complex organism,s the average lifespan of a species is 4 million years.
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