"The Copernicus Complex" by Caleb Scharf

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Notes:

The Sun orbits around a variable point – the centre-of-mass or balance point of all objects in the system. This point is close to the observed surface of the Sun –well offset from its core.

Sun is 1,392,686 km across. It’s equal to 218 times earth’s diameter

Titius-Bode Law helps to calculate distance of each planet from the Sun. First, we need to remember a series 0, 3, 6,12,24, 48,96, 192. Next, we need to add to each number 4 and divide it by 10 to get the mean distance of each planet from the Sun in astronomical units.

Therefore, Mercury is 0.4 of distance of earth from the Sun, Venus is (3+4)/10=0.7, Earth is (6+4)/10=1, Mars is (12+4)/10 = 1.6 AU, Ceres is (24+4)/10=2.8 AU, Jupiter is (48+4)/10=5.2 AU, Saturn is (96+4)/10=10 AU, Uranus is (192+4)/10=19.6, Neptune is (384+4)/10=38.8 AU (actually 30 AU) and Pluto is (768+4)/10=77.2 AU (actually 39.4 AU)

75% of all stars are less than half of the Sun and less than a few percent of its luminosity. Within 20 light-years of us there are 8 stars like the Sun or slightly larger, but there are 101 stars that are smaller.

Every year the Moon recedes from us by almost 4 cm, and the Earth’s day slows by 1.5 microsecond. Some 600 million years ago the Earth’s day was about 21 hours.

There are three domains of Earth’s living organisms:

1. Bacteria – simple single-celled organisms. They can survive as individuals, but more often operate as colonies. Their cells tend not to contain any additional complex internal structures.

2. Archaea (old ones). They have no nucleus, but possess genes.

3. Eukaryotes. Their cells are much larger and more complex and keep their genetic material protectively bound up in a nucleus. They make up plants and animals.

Genetic studies suggest that between 123,000 and 195,000 years ago, the population of biologically modern humans declined dramatically, from more than 10,000 to just a few hundred. A climate change is partially blamed. All of us alive today come from this tiny group of people living somewhere in central or southern Africa.

Neanderthals drifted to extinction about 28,000 years ago. The genetic code of people from Eurasia contains as much as 1 to 4 percent of the Neanderthal code.

Although most mammalian species alive today can digest milk sugar as infants, they lose that ability as adults. Some 9000 years ago that changes and 80% of people of European descent can digest it. For others, only a third of humans can do it.