Astronomy

Astronomy

Milky Way Galaxy

  • 100,000 light years
  • 100 billion stars
  • 283 million years for a spiral rotation
  • 5-10 billion people
  • Map 10-20 star systems

Astronomical Phenomenon

  • Halley's Comets
    • Ice Comet
    • Meteorites
    • Metals
    • Asteroid Belt
    • Asteroids

Planets and satellites: Geological composition

    • Mercury: iron, nickel, silicates
    • Venus: silicates, iron, nickel
    • Earth: silicates, iron, nickel
    • Moon: silicates
    • Mars: silicates, iron, sulfur
    • Jupiter: hydrogen, helium
    • Titan: water ice, silicates
    • Uranus: ices, hydrogen, helium
    • Neptune: ices, hydrogen, helium
    • Triton: silicates: water, other ices
    • Pluto: silicates, water, other ices

Solar Nebula

    • Hydrogen (gas): 77%
    • Helium (gas): 22 %
    • Water (ice): 0.6 %
    • Methane: 0.4 %
    • Ammonia: 0.1 %
    • Rock and metal: 0.3 %

Asteroid Dating ( 20 largest asteroids)

    • 1801 – Ceres – 940 km
    • 1802 – Pallas – 540 km
    • 1807 – Vesta – 510 km
    • 1849 – Hygeia – 410 km
    • 1910 – Interamnia – 310 km
    • 1861 – Cybele – 310 km
    • 1868 – Europa – 280 km
    • 1866 – Sylvia – 280 km
    • 1804 – Juno – 275 km
    • 1852 – Psyche – 265 km
    • 1899 – Patientia – 265 km
    • 1854 – Euphrosyne – 250 km
    • 1851 – Eunomia – 245 km
    • 1892 – Bamberga – 245 km
    • 1868 – Camilla – 235 km
    • 1904 – Herculina – 230 km
    • 1857 – Doris – 225 km
    • 1854 – Amphitrite – 225 km
    • 1852 – Fortuna – 220 km

Carbon Dating

    • Carbon dating 14, in the late 1940's Willard Libby discovered a way to determine the age of dead plants and animals remains.
    • All living things are made of carbon. A very small amount of this carbon is carbon-14 a radioactive isotope. One a plant or animal dies, the carbon-14 in its body begins to disintegrate. Since we know how fast carbon-14 decays, we can determine the approximate age of organic matter.

Comets

    • Space probe Giotto flew by the famous comet of all, Halley's comet, in 1986.
    • Swift Tuttle comet takes 128 years to orbit the Sun and won't pass Earth for another 100 years
    • Comets are big dirty snowballs of icy clumps outside Pluto's orbit

Meteorites Types

    • Primitive meteorites (chondrites)
    • Carbonaceous: silicates, carbon compounds, water
    • Primitive Stones: silicates, iron
    • Differentiated stones (achondrites): igneous silicates
    • Stony irons: igneous silicates, iron, nickel
    • Irons: igneous silicates
    • A meteor shower is when Earth's orbit passes through the dust and ice shed by a comet, the particles burn up in our atmosphere

Meteorite Dating

    • Samarium (Sm-147) 106 billion years
    • Neodymium (Nd-143) 106 billion years
    • Rubidium (Rb-87) 48.8 billion years
    • Strontium (Sr-87) 48.8 billion years
    • Thorium (Th-232) 14.0 billion years
    • Lead (Pb-208) 14.0 billion years
    • Uranium (U-238) 4.47 billion years
    • Lead (Pb-206) 4.47 billion years
    • Potassium (K-40) 1.31 billion years
    • Argon (Ar-40) 1.31 billion years

Meteorite Solidification Ages of Meteorite groups

    • H group chondrites 4.50 * 0.04 by
    • L group chondrites 4.43 * 0.05 by
    • LL group chondrites 4.51 * 0.03 by
    • E group chondrites 4.45 * 0.03 by

Planetary Systems