sowmiya.space

Cosmos

Dec 30, 20249 min read

Author: Carl Sagan

  • Percival Lowell - canals on mars
  • Robert H. Goddard  being inspired by Percival Lowell stories.
  • Chinese inventing gun powder/rockets for religious purposes and Europeans using it for weapons and eventually space rockets
  • Percival Lowell the crazy mars guy convincing everybody there’s canals on Mars just by looking from telescopes. He claimed it to be like American southwest terrain. But mostly the guy was just seeing things, other astronomers were skeptic.
  • Mars Jars - the author ran an experiment simulating the conditions of Mars in a jar and saw if any microbes would survive in it. And ofc they all die in a few days. When small level waters were present the microbes grew though.
  • Temp -80C to 0 range. Atmosphere of Co2 and N2. High UV.
  • All the below are stationary landers and not rovers. Rovers
  • 1971 - Soviet Mars 3 - It failed, landed, sent one picture back and died. They usually try and land these rovers were there is least dust, yet this one got stuck in all the dust.
  • Viking 1 and 2
  • 1976 - US Viking 1 and 2 landing - They put parachutes on the rovers to land, because the atmosphere there is not dense.
  • To detect rough and softer spots on Mars surface. They used radar surveys. Both rough and soft spots would appear poorly reflective. They wanted to avoid both so it was okay.
  • They have pictures of mars from orbiters though, like the mariner.
  • But because they choose these safe spots, the area of landing also is dull and of no interest.
  • Viking 1 landed in Chryse and 2 in Utopia, same year 3 months apart.
  • The vikings had a bunch of biological experiments on them, small test tubes with some chemicals, that will react with soil to see what happens.
  • The results are conveyed using Orbiters and orbiters relay back to earth.
  • Wolf Vishniac built biological experiments to send on Vikings, but budget cuts took it away. The guy had spent 12 years working on it. The guy instead went into Antartica (a similar dry environment) to test his experiment. And he died there :(
  • Initial Viking experiments on soil show some sort of microbe activity, turns out it was just some catalysts or enzymes present in the soil.
  • They didn’t want to bring any sample back, due to fears of biological risks - pandemics. Author mentions how nations have their labs with bio weapons, but it’s all well contained - haha covid coughs.
  • Gases in polar ice caps - the idea is that Mars once had gases, but they are trapped in it’s ice caps now. We could melt them, form canals, bring out gases.
  • Either paint the caps black, so it’s a absorber of sun rays and melts. Some form of algae or life to break it. Nevertheless, will take centuries to do it.
  • This is called Terraforming. (Like terraforming mars XD #amadeusz)
  • Basically, they want to increase temp, increase water, oxygen, atmospheric density and so on.
  • 1979 - Voyager 2 - Jupiter
  • Redundant parts so if some component fails then it takes over. Not solar powered as so far from sun. Relies on a small internal nuclear power plant.
  • Radiation from Jupiter itself can fry the spacecraft, so it needs to be careful voyaging around.
  • Launched in Aug 1977. Went beyond mars, jupiter, saturn, then gravity of saturn propels it towards Uranus. Then Neptune and just away and away. It ain’t comin back.
  • Holland after independence from Spain becomes a innovation house. But were the Dutch nasty?
  • Leeuwenhoek, Huygens, Rembrant, Galelio etc.
  • Galileo built an astronomical telescope on top of some dutch spyglass. He discovered sunspots with it.
  • Leeuwenhoek thought the microbes he saw were cute :P
  • Huygens does a lot, measures size of some planet , finds venus is completely covered in clouds, satyen covered in rings, pendulum clocks, balance spring.
  • Galelio misunderstood saturn’s rings for ears. Christiaan Huygens with a stronger telescope fixed it.
  • Jupiter
  • Outer 2 moons of Jupiter, are not hard. They must contain radioactive traces of elements and could not have escaped surface. Thus their cores are slushy oceans.
  • Voyager discovered volcanoes on Io. First discovery of volcanoes outside of earth.
  • Volcanoes of Io are a result of Tides
  • Had Jupiter been more massive, it could have been the second sun :D It’s basically a failed star! If we had two stars, we would have sunlight all day long.
  • Also Jupiter’s atmosphere is sooo pressureful that it makes Hydrogen lose electron and become liquid metal, a feat unachieved yet on earth synthetically even.
  • Saturn
  • Titan the largest moon on Solar system, the only one with a substantial atmosphere.
  • There may be a possibility of life there.
  • Space vehicles need to parallely run and slow down to see the saturn rings as asteroid chunks, otherwise they just seem like lines.
  • Voyager
  • It eventually would reach the heliopause, where pressure of interstellar protons and electrons become greater than the miniscule pressure exerted by solar wind.
  • Backbone of the night
  • He writes that nice story or passage of how an ancient man would have thought about the skies and stars
  • Milky way the name comes from a legend that Hera wife of Zeus squirted milk from her breasts ans hence the milky way
  • After all the bullshit traditions, 2500 years ago, the Ionians said everything is made of atoms. It all started there. The explorative science. China or India could have also started it if given time. Some Ionians below.
  • Thales of Miletus - first Ionian scientist. Geometry guy, proved lower angles are equal in an isosceles triangle. He said everything came from water, lands came from beneath. Unlike some god creating it. He also proved that philosophers could make money. Rented out olive mills cheap the previous year and rented back for much higher rates. He predicted a better olive season ahead. Aristotle wrote about this in his Politics book.
  • Anaximander of Miletus - Examined moving show of sticks and derived length of year and seasons. Started ideas of evolution. If human babies were born directly then we would just die, so should have evolved.
  • Polycrates - Weird guy, started as a caterer then an international pirate. Built fortified walls, canals and stuff.
  • Theodorus - Invented key, ruler, carpenters square.
  • Hippocrates - Medicine guy. Made medicine an empirical science just like physics or chemistry.
  • Empedocles - performed the first experiment. Showed that air is also a substance with particles in it.
  • Democritus - Introduced the term atom. Started the theory of limits. Plato burned all his books later because they were practical and not just theory and only something slaves would do. Democritus also valued friendship and didn’t like women or sex.
  • Anaxagoras - Showed that moon shines by reflection.
  • Pythagoras - you know who. He deduced earth was a sphere. Him and his followers formed a sort of mathy cult though. They ended up propagating theories that math was perfect. They hated irrational numbers.
  • Five perfect solids. The fifth solid was expected to represent a fifth element of life. The word quintessential comes from it.
  • Kepler was slowed down because he also expected the planetary motion to be perfect and circular.
  • Eventually once merchant tradition started. Slaves happened. And people got lost there. They thought science was stupid especially the experimental mechanical kind. The upper class had to maintain status quo. Aristotle and Plato were on this too fyi. Same in India and China too. It put a brake on science and took a while to come back.
  • Christiaan Huygens drilled holes in a plate and held it up to sun. He wanted to find which hole was as bright as the sirius star from previous day. That way he could tell how much farther sirius was than sun.
  • William Herschel - By mistake told that solar system is in the center of milky way.
  • Harlow Shapely - then found that the size and brightness of the milky way is not right. And the brighter clusters of stars form it’s center and solar system is rather sparse and is away from center. If we were in the center our skies would be brighter and fun.
  • Chapter - Travels in space and time
  • Talks about constellations and how they change shapes when we travel to another side and look at them (with simulations) - big dipper, orion, leo, Andromeda.
  • If some star far away blew up then we would probably not see the explosion on earth or any other change until that light could reach us. Which could be decades.
  • Theory of relativity
  • Michelson morey experiment - that debunked the aether does not exist and light just travels in vacuum. Einstein used these results in his theory.
  • Neurons in brain don’t pass signals that fast. Computers do it super fast. Brain pretty slow :P
  • Projects to reach the stars - orion, daedalus.
  • We could build a spacecraft that slowly accelerates at 1g or 9.81m/s^2. Then in 1 year we’ll reach speed of light.
  • How humans age slowly in space if speeds are high enough to dilate time.
  • How some scientists believe in parallel worlds and how world would be different if some events had gone differently.
  • Alchemists and their fame. How European nobility was transferring large sums of money to make gold. But phosphorus, antimony and mercury were discovered this way
  • Stars
  • Neutrinos - neutrino flux
  • Black holes
  • The big bang
  • The milky way rotates once every quarter billion years
  • Stars on the wisps of the spirals of galaxies die and give rise to new ones. It’s also on these wings that weird events happen.
  • When sun passed through a spiral arm it is suspected the ice ages happening reason
  • In this epoch the solar system is between spiral arms.
  • Doppler effect
  • Humason and bubble found that distant galaxies were red shifted, which meant they were moving away or expanding. The universe is expanding and a proof of the big bang.
  • Theres a reference to how the Hindu religion refers to cosmos as an expanding thing.

Stellar Map