INNER PLANETS OUTER PLANETS IR picture 105 ly

INNER PLANETS

OUTER PLANETS

IR picture 105 ly Scorpius constellation Galactic center

THE LOCAL GROUP 106 ly ANDROMEDA 2 x 106 LY from us

GALACTIC STRUCTURES SPIRAL 30% LENTICULAR ELLIPTICAL -majority IRREGULAR

ACTIVE GALAXIES RF JETS AND BLACK HOLE – NGC 4261

GALAXY CLUSTERS VIRGO COMA FORMAX

RED SHIFT SURVEYS TO 150 Mpc, ~2% to edge Filaments and Sheet-like Structures And Bubble-like voids

EPICYCLES - COPERNICUS

KEPLER’S LAWS The orbits of the planets are ellipses, with the Sun at one focus of the ellipse. The line joining the planet to the Sun sweeps out equal areas in equal times as the planet travels around the ellipse.

Galileo’s drawing Huyghen’s drawing Hubble image

KEY QUESTIONS: • WHY SIX PLANETS ? • WHAT CONTROLS THE SIZE OF THEIR ORBITS KEPLER MYSTERIUM COSMOGRAHICUM A precursor to cosmographical dissertations, containing the cosmic mystery of the admirable proportions of the Celestial Spheres, and of the True and Proper Causes of their Numbers, Sizes, and Periodic Motions of the Heavens, Demonstrated by the Five Regular Geometric Solids Numbers p =3. 14159…… f = 1. 6180339…. Golden ratio, Golden number, Golden Section A C B AB/AC=AC/CB

Bode’ Law Distances of planets from Sun M. 39, V. 72, E 1. 0, Mars 1. 5, J 5. 2, SAT 9. 5, UR 19, N 30, PL 39 Start with 0, 3, 6, 12, 24, 48, 96, 192, 384 Add 4 and divide by 10. 4, . 7, 1. 0, 1. 6, 2. 8, 5. 2, 10, 19. 6, 38. 8 Missed Neptune and no planet at 2. 8 Asteroid belt -> rocks (40000) few km size

Newton’s laws • Newton’s laws of motion • Frames of reference • Newton’s law of Gravitation

I: NEWTON’S LAWS OF MOTION Begin by stating Newton’s laws: Newton’s first law (N 1) – If a body is not acted upon by any forces, then its velocity, v, remains constant Note: – N 1 sweeps away the idea of “being at rest” as a natural state.

Newton’s 2 nd law (N 2) – If a body of mass M is acted upon by a force F, then its acceleration a is given by F=Ma Note – N 2 defines “inertial mass” as the degree by which a body resists being accelerated by a force. – Another way of saying this is that force = rate of change of momentum (rate of change of mv). Newton’s 3 rd law (N 3) - If body A exerts force F on body B, the body B exerts a force –F on body A.