The Living Cosmos
Cambridge, 2011(paperback, update)
An astronomer at Univ of Arizona, this book explores the possiblility of life in the universe, astrobiology.
1. The Unfinished Revolution
p 5 Good survey of ancient persons and ideas. Next several pages a history of ancient thinkers, basis for a map of ideas.
p 13 Sings the praises of Bertrand Russell - "heroic figure in the history of thought", productive work into his 80s, only desire to learn more mathematics that kept him from suicide, jailed for antiwar activity during WWI and produced great work even there.
p19 Interesting anecdotal history of Tycho Brahe
p20 Kepler used Brahe's data to form his three laws. Corresponded with Galileo. Anecdotal history of Kepler.
p20 Galileo's discoveries - mountains and valleys on Moon, so wasn't perfect sphere, telescope, discovered 4 moons of Jupiter, resolved stars in Milky Way. Corresponded with Kepler in 1597 about heliocentric model.
p22 Newton in one year invented calculus, discovered the law of gravity, defined the properties of light, made improvements in telescope. Was confined in Britain on plague protection quarantine.
p22-23 Anecdotal history of Newton.
p23 Hershel's and Parsons telescopes
p29 Vesto Slipher. Introduced the red shift into the investigation by Hubble. Used Cepheids to get distance to galaxies. Almost all galaxies showed red shift (Andromeda being one exception)
p31 Description of general relativity
p32 Interesting. Discusses E=mc2 "So if anything with mass is subject to gravity, and energy and mass are equivalent, then light has mass, too, which makes it subject to gravity." This is just the kind of statement I'm being jumped upon about in HyperPhysics.
p33 Lemaitre and the big bang, 3K bkg. Interesting that he gives such short shrift to Penzias and Wilson, commenting only that they "blundered onto this signature of the big bang". Comments that big bang is very robust model.
p33-34 Dark matter, dark energy and inflation
p35 Gives number of 60 billion for galaxies, 1022 stars.
p37 Overview of large telescopes, Keck 10m with hexagonal mirrors, but Hubble more powerful. Interesting overview of Hubble capability. Can read book at 3 miles, see a 100w bulb at 25 times the moon's distance, see 10 billion times as deep into the universe as the human eye. Relative to eye achieves x100 from detectors which detect essentially every photon, x104 from aperture, x104 from extension of observation time.
p38 Hershell descovered IR from space with thermometer, Ritter discovered UV with AgCl solution
p39 Hertz discovered radio waves and inspired Marconi, Reber made a radio frequency dish, Roentgen discovered X-rays, and now all are being used to explore space.
p41 Microwaves see universe when it was <0.003% of current age, Hubble sees objects at 5% of current age.
p40-42 Various scale models of the solar system and universe
p43 Model in time. Our civilization in last second of a year which represents the age of the universe. Technology in last 1/10 of second.
p44 Chemistry timeline Lavoisier - Dalton -Fraunhofer
p46 The presumption of astrobiology is "since carbon and water exist everywhere in the universe" .. the "Raw material for life is abundant.."
p46 Hooke credited with first publication of microscope observations, coined the term "cells". Leeuwenhoek discovered bacteria and other microscopic life late 1600s. Pasteur, Mendel and Darwin cited.
p48 Under heading "Astrobiology Grows Up", discusses Watson& Crick, Oparin & Haldane, Miller & Urey. Mentions Drake
2. Life's Origins
p52 The dating of a zircon crystal to 4.4 Gy prompts him to quote Blake "to see the world in a grain of sand, and a heaven in a wildflower".
p52 Fractional composition of human body, water 60% by weight
p53 living organisms 40% carbon,nitrogen, oxygen
p53-54 brief big bang chronology
p54-55 Composition of universe, graph on p55. Uses decks of cards to illustrate rarity of atoms other than H and He.
p55-56 Nice section on the building up of the elements. Section titled "Cauldron of the Elements".
p57 Low mass, high mass star comparison. "Low-mass stars end up with a seething core of carbon, with some nitrogen and oxygen. High-mass stars have cores of iron, not the solid iron of a wrecking ball but a bizarre, dense billion-degree gas."
p57-58 Elegant language to describe white dwarfs, neutron stars, supernovae and heavy element buildup.
p58 Deep Time "time's 'arrow' seems to be an emergent property of large collections of atoms." Looks like he and Sean Carroll are on the same wavelength.
p61 Quotes 750,000 years from Greenland ice cores and several million from layers in Lake Baikal. Earth's orbit from 6% to 0% elliptic with a period of 100K years from deep sea core samples. Earth's axis tilt 21.5 to 24.5 degrees with 41K year period. Earth precession 23K years.
p62 Watch 32,768 Hz Cesium clock.
p64 Carbon dating with some detail. Zircon dating. Bare statement "Shroud of Turin was a fake."
p66 Bottom - more about zircon.
p67 Quotes 4.54 +/- 1% Gyr for meteorite age.
p67-68 Oldest preserved remains of life - gives ages for lots of examples.
p68-69 Very nice articulate description of fossils.
p70 Stromatolites >3Gyr Shark Bay West Australia, cyanobacteria, cyanobacteria >2 Gyr in Ontario.
p71 Cholesterol remains in fossils - biomarkers.
p72 Fairly strong evidence to 3.5Gyr
p72 12C13C ratio by mass spectrometry. Lighter carbon higher speed, absorbed more often by enzyme in photosynthetic microbes, results in 5 parts per 1000 less 12C in the limestone in which the microbes live.
p73 Description of Miller-Urey
p76 Flowchart of life
p76 Replacement rate of cells - interesting discussion. "Every five days you get a new stomach lining. You get a new set of skin cells every six weeks and a complete replacement of your liver cells every two months. Each year, 98 percent of the atoms in your body are replaced. Constant replacement of components and energy flow within an unchanging structure is the hallmark of living organisms."
p77 His summary description of entropy.
p77-78 Entropy and life - a reasonable discussion.
p78-79 Discusses information, hints at Shannon information, cites Orgel and specified information, but skirts the problem of how specified information arises.
p80 Jumps to (1) use energy, (2) organize matter, (3) store information, (4) reproduce and then starts evolution discussion.
p81-82 How did life start? Cites Jack Szostak. Sketch to protocell.
p83 Top, his response to YEC and intelligent design. Mentions William Paley. Paragraph 5 is party line on intelligent design.
p85 Gets to RNA world and posits transition to DNA. Cech and Altman, RNA as catalyst, RNA enzymes called ribozymes.
p85 RNA and "RNA world" from Woese, Crick and Orgel. Discussion of ribosome. Nice analogy of ribosome to DVD player that takes DVD and "translates" it to a movie. discussion of rna's role in the ribosome.
p86 "We've neatly sidestepped the chicken-and-egg problem - RNA embodies both information and action in the cell." A little too neatly, I would think - more like "swept under the rug".
p86 Szostak and the first replicator. Orgel quote, particularly on the transition to RNA world, "Anyone who thinks they know the solution to this problem is deluded." but then "Anyone who thinks this problem is insoluble is also deluded." In the face of the daunting numerical problems he proposes autocatalytic processes, clay surfaces, and makes the leap to RNA this way.
p87 Back to Szostak and projecting from RNA to ribozymes. Last sentence "All the requirements for growth and replication are satisfied." I would ask "Are you satisfied with that statement?!"
p88 Discussion of the first cell. Quotes Lynn Margulis "To go from a bacterium to people is less of a step than to go from a mixture of amino acids to a bacterium."
p88 Depicts Szostak as concluding that RNA can self-replicate, and concluding that clay has a part. Attributes it all to Darwinian evolution. Leans a lot on Szostak, which seems appropriate
p88-89 RNA replication discussion. Includes the clay proposal. Suggests spontaneous replication of RNA. 89 mid, looks really shaky to me - unsupported assertions. Paragraph 3,"At this point, we have primitive precursors of the attributes of living organisms: containers that concentrate chemical activity, macromolecules that can carry information and replicate, and a mechanism for conveying selective advantage to the best replicators. The last is crucial because it means that Darwinian evolution could have operated in the dark ages before DNA and modern cells."
p89 Sketch of vesicle formation
p90 Diagram of chemical evolution to Darwinian evolution. The GAIA hypothesis, James Lovelock along with Lynn Margulis. Discusses feedback loops and the regulation of the Earth's biosphere. Looks like an incredible amount of faith.
p91 "Twenty percent of the molecules in the air were produced by the respiration of tiny microbes that evolved several billion years ago."
p91 Sun has increased its heating of the Earth by 25% since it was formed. The salt concentration is 3.4% compared to disaster at 5%, salt role of bacteria.
p92 The carbon cycle as a life-preserving feedback loop.
3. Extreme Life
p94 Waxes poetic about microbes and the extreme range of conditions under which they can thrive.
p94 "Seeing the weirdness of life on Earth expands the definition of the biosphere and makes it more likely that there will be habitable places elsewhere in the Solar System. Most cosmic environments are inhospitable, but 'inhospitable' is life's middle name because primitive organisms thrive in such an amazing range of physical conditions."
p94 "Advanced forms of life like mammals may be unusual, because they are able to thrive in such a narrow range of physical conditions. Across the cosmos, planets covered by a web of extremophiles may be the norm. It's difficult to feel kinship with bacillus infernos, and even scientists must guard against anthropocentric thinking. We say that life is hardy, that life is resourceful. Perhaps - on millions of planets beyond the Solar System and with no deeper meaning than rocks or clouds - life just is." A kind of manifesto for the astrobiologist, albeit with a materialistic worldview built in.
p96 Tree of life by Stephen Jay Gould
p97 Haekel's tree of life
p98 Ribosomal DNA as tool for forming tree of life. Discusses central dogma.
p99 Phylogenetic tree of life from mitochondrial DNA
p100 Numbers for species and Haldane's beetle quote. Describes "lumpers" and "splitters" in approach to counting species.
p101 40 kingdoms of bacteria
p101 DNA overlap, e.g. 99% with monkeys
p102 cytochrome-C tree of life
p103 "gene transfer is the way bacteria gain resistance to antibiotics." Discusses gene transfer from bacteria to eukaryotes and uses it to undermine the idea of a common ancestor.
p104 Treats thermophilic origin of life as highly probable. Discusses protists, but I don't really know what that means. But he says "All eukaryotes including us are either protists are descendants of protists."
p106 22nd amino acid pyrrolysine in thermophiles
p106 "Life on Earth began in extreme conditions, probably near high-temperature, toxic hydrothermal vents."
p107 Bacterial superheros bacillus infernus and dernococcus radiodurans
p108 tardigrade discussion and picture
p113-114 Discussion of pH with examples - look at adding scale to HyperPhysics
p116 Extremophiles methanogens and halophiles
p120 New idea to me - bacterial biological communication, with some phenomena like glowing which only turns on when the colony concentration reaches a critical concentration. Utilized by a type of squid with internal bacterial colonies.
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