1 / 15

Mountains on the Moon

Mountains on the Moon. Galileo observed the mountains of the Moon with his telescope Estimated their elevation correctly. Artsy eyepiece sketches. Galileo was trained as an artist This allowed him to correctly reason that these patterns means a rugged surface. Galileo’s Genius.

brilliant
Télécharger la présentation

Mountains on the Moon

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Mountains on the Moon • Galileo observed the mountains of the Moon with his telescope • Estimated their elevation correctly

  2. Artsy eyepiece sketches • Galileo was trained as an artist • This allowed him to correctly reason that these patterns means a rugged surface

  3. Galileo’s Genius • Careful observation of a phenomenon • Deriving conclusions from “data” • Making new predictions • Publishing results “for everyone” [in Italian] • Anticipates his opponents arguments, and nullifies them by using stringent logic

  4. Aristotle easily falsified by experiment – but emphasis was not on observation How people thought about projectiles up until the Renaissance: the cannonball moves in almost a straight line, until it runs out of impetus and falls on the house. WRONG!

  5. Galileo gets it right Strobe photograph Galileo Galilei’s notebook In fact, all projectiles fall in exactly the same way, regardless of what they are or weigh!

  6. Key question:Where are things? Catalogued positions of planets in Uraniborg and Prague Working without telescope Data ten times as accurate as before Died at banquet binge drinking Tycho Brahe – The Data Taker Tycho Brahe (1546–1601)

  7. collects detailed and accurate (1-2’ accuracy) observations of stellar and planetary positions over a period of 20 years His research costed 5-10% of Danish GNP shows that comets and novas are extralunar contrary to Aristotle Shows that stars can change (Supernova of 1572) Proves that comets are superlunar Tycho Brahe Tycho Brahe observing

  8. Measuring distances with the Parallax • The closer an object is, the more relocated it appears with respect to the fixed stars from different points on Earth

  9. Johannes Kepler–The Phenomenologist Key question: How are things happening? Major Works: Harmonices Mundi (1619) Rudolphian Tables (1612) Astronomia Nova Dioptrice Johannes Kepler (1571–1630)

  10. Kepler’s Beginnings Astrologer and Mystic Tried to find “music in the skies” Tried to explain distances of the 5 known planets by spheres resting on the 5 mathematical bodies  pre-scientific

  11. Kepler’s First Law: Orbit Shape The orbits of the planets are ellipses, with the Sun at one focus

  12. Ellipses a = “semimajor axis”; e = “eccentricity”

  13. Conic Sections From Halley’s book (1710)

  14. Kepler’s Second Law: Motion in Time An imaginary line connecting the Sun to any planet sweeps out equal areas of the ellipse in equal times

  15. Kepler’s Third Law: Relating Orbits The square of a planet’s orbital period is proportional to the cube of its orbital semi-major axis: P 2 a3 Jupiter:53 / 122 = 125/144 ~ 1 a P Planet Semi-Major AxisOrbital Period Eccentricity ____ P2/a3 Mercury 0.387 0.241 0.206 1.002 Venus 0.723 0.615 0.007 1.001 Earth 1.000 1.000 0.017 1.000 Mars 1.524 1.881 0.093 1.000 Jupiter5.203 11.86 0.048 0.999 Saturn 9.539 29.46 0.056 1.000 Uranus 19.19 84.01 0.046 0.999 Neptune 30.06 164.8 0.010 1.000 Pluto 39.53 248.6 0.248 1.001 (A.U.) (Earth years)

More Related