Today’s Objectives: S.W.B.A.T.

Observe an overview of history of Astronomy - review

Name 3 contributions Tycho Brahe contributed to Astronomy

Identify Tycho’s model of the universe

Name an observation Tycho observed that went against teachings of the time.

Activities:

Notes/discussion

Video clip review – to review unit 1 material covered to date

Ptolemy – Copernicus worksheet

Work on any missing work/organize notebook

Tycho Brahe – 1546-1601 AD Astronomy’s’ greatest naked eye observer

Made instruments so that he could accurately measure the movement of celestial objects

His measurements were precise to angles of 1/60 of a degree, 1 arc minute

Was the astrologer for the King of Denmark

King gave him a castle observatory called: Uraniborg on the island of Hven

Observation made: *** Mostly known for 20 years of

accurate planets and position data Supernova of 1572 in constellation of

Cassiopeia Comet of 1577, using geometry proved

the (comets) were not an atmospheric disturbance as taught, but traveled far beyond the moon and passed through the crystals spheres (broke the crystal sphere concept) text covet(pamphlet)

His observations of the planets did not match the models of the time, he tried to design a new one, and Brahe firmly believed the geocentric concept had to be true. Spent the rest of his life trying to come up with a better model

(His best idea or model was called the Hybrid geocentric)

Brahe had an overbearing personality, which got him in trouble with other nobles of the time. Fought a duel and lost the tip of nose was cut off (know as the man with the gold or silver nose) also was very overweight and died from over eating and drinking.

Today’s Objectives: S.W.B.A.T.

Observe an overview of history of Astronomy – review video clip

Describe Kepler’s contributions to astronomy

State Keplers 3 laws of planets

Calculate distance or revolution using Keplers 3rd law (lab & worksheet)

Activity:

Warm-ups

Quiz – overview on current unit

Video clip review –past astronomers to Tycho

Notes and discussion

Video clip Kepler’s laws

Kepler’s Law example problems

If time allows Tycho Brahe – worksheet review start

Johannes Kepler 1571-1630

Born to a poor family in Germany

Was the oldest of 6 childern

1st job was teaching mathimatics, later worked on the Annual Almanac of Astological and Weather, in 1595 some of his predictions where correct and he gain reputation as an astrologer and seer ($$$$$$$)

Wrote a book called: Mysterium Cosmographical

In the test he had the 5 regular solids as the key to the spacing or space between the so-called crystal spheres

After working with Tycho Brahe’s observational data and working with ancient models of the cosmos, he began to accept the Copernican model (heliocentric) to be the correct one.

In 1609 wrote: Astronomy Nova – new astronomy

Book explained 3 laws of planet motions (Kepler’s Laws)

Law 1, The orbit of planets are ellipses with the sun at one focus

-Terms: focus, Major axis, semi-major axis, aphelion, perihelion

Law 2. a line from the planet to the sun sweeps over equal areas in equal intervals of time

-** planets travel faster when close (perihelion) to the sun and slower when far from the sun.

Law 3. a planets orbital period squared is proportional to its average distance from the sun cubed

- If one knows how long a planet goes around the sun they can find its distance for the sun or visa-versa

- law applies to orbiting moon, satellites etc……

- in Keplers laws distance in AU units and period is in years

- mass will be use in future reference are expressed in solar masses.

p² (in Earth years) = a³(or d³) (in astronomical units)