natural sciences
lecture demonstrations
back to demonstrations index

Astronony and Astrophysics

  1. Astrophysical Principles -- Radiation
    • Inverse Square Law Large climbing frame shaped to show inverse square distribution. (xl) (T+++)
    • Tower of Spectra. Assembly of three discharge tubes and white light source for spectral analysis. (m) (T)
    • Sodium Absorption Burning of sodium bicarbonate in Bunsen flame produces sodium absorption lines in continuous spectrum. (m) (T+) ***
    • Boltzmann Distribution. Mechanical analog of energy level populations used in estimating the surface temperatures of stars (intensity of absorption lines). (m) (T+)
    • Collisional Broadening Na D-doublet absorption lines broaden into one large absorption band due to increase in pressure/temperature. Stark effect. (l) (T+) ***
    • Piano The visible part of the electromagnetic spectrum is represented by less than an octave of the keys; UV, IR, and microwaves are also indicated. (l) (T) ***
    • Relativity Train Demonstration of time dilation and length contraction gedanken experiment using a train on a track. (xl) (T++) ****
    • Bouncing Photon. A photon (modeled by a bouncing ping-pong ball) is observed from two reference frames and provides the motivation for time dilation. (xl) (T++)
    • Doppler Ball Plastic shrieking quasar to throw past your audience. (s) (T) ***
    • Doppler Turntable Two speakers, one at each end of rotating platform; beating due to frequency shift of speakers travelling in opposite directions. (l) (T+) **
    • Doppler Whirler A high-pitched alarm on the end of a rope is whirled about the head. (m) (T) ***
    • Doppler Tuning Forks Run towards the blackboard carrying a tuning fork... (m) (T) **
    • Doppler Effect. Listen to the doppler shift of light as a moving mirror reflects laser light onto a photodetector. (l) (T+)
    • Elastic Light Wave drawn on elastic sheet shows redshift due to expansion of space. (m)(T) **
  2. Astrophysical Principles -- Gravitation
    • Ellipse Drawing Board. Drawing stencil for blackboard use. (m) (T)
    • Foucault Pendulum Plane of pendulum oscillation appears to change due to rotation of Earth. (l) (T+++) **
    • Precession Globe Globe pivoted so north pole can precess. (m) (T) **
    • Moon Orbit Model Mechanical model of Earth-Moon orbit around Sun. (m) (T) **
    • Cavendish Experiment Calculation of gravitational constant, with accompanying apparatus model. (l) (T++) ****
    • Kater's Pendulum A physical pendulum with two adjustable knife edges for an accurate determination of "g". (m) (T) **
    • Newton's Apple  Apple electronically released from platform; fall time given by special circuit and digital display. (l) (T++) ****
    • Potential Well Orbiter Orbital motion simulated by ball rolling on wooden potential well. (m) (T) *
    • Gravitational Field Surface 1m diameter rubber sheet acts as curved space for ball bearing masses. (m) (T) *
    • Gravitational Lens Laser and plastic lens with curvature to simulate bending of light by massive object. (m) (T+) ***
    • Saddle Shape Universe Curved space segment for open universe geometry. (m) (T) *
    • Spherical Blackboard 1m black sphere for your closed universe artwork. (m) (T) ***
  3. Astro-archaeology
    • Equatorial Ring Model of Ptolemy's ring used to measure the length of the year. (m) (T+) *
    • Stonehenge Static model of site; can be used with light source to simulate a mid-summer's morning  (m/l) (T/T+) ****
    • Tycho Brahe's Sextant. Scale replica of Brahe's instrument. (l) (T+)
    • Astrolabe Model. Device to locate planets in heavens; large scale reproduction of mediaeval instrument. (m) (T)
    • Eudoxos Hipoped Machine Electrically driven machine to represent retrograde planetary motion according to Aristotle's theory of concentric spheres. (l) (T) ***
    • Ptolemaic Epicycle Machine. Driven model of Earth and Jupiter's motion based on Ptolemy's epicycle theory. (l) (T)
    • Armillary Sphere Model to show celestial sphere; larger version has capacity to show lunar motions. (m/l) (T/T) ***
    • Copernican Orrery. Driven model of Earth-planet system based on Copernican theories for retrograde motion. (l) (T)
    • Shadow Orrery. Projection of planetary shadows from illuminated Earth illustrates Copernican theory of retrograde motion. (l) (T+)
    • Kepler's Machine Working model to show Kepler's 1st and 2nd laws and the equivalence of the area law to the law of equants. (l) (T+)
    • Kepler's Universe Model of the solar system based on the five perfect solids. (m) (T) **
  4. The Universe
    • Earth Globe. How Earth looks from space, plus labels. (m) (T)
    • Centrifugal Eggbeater Spinning frame that demonstrates equatorial bulge (oblateness). (m) (T) ***
    • Lunar Globe. Spherical relief map of Moon. (m) (T)
    • Spherical Blackboard 1m black sphere for work on a two dimensional closed universe. (m) (T) ***
    • Inflating Universe Large weather balloon; create your own expanding universe. (l) (T+) ***
    • Jupiter's Satellites Static model of satellite orbits. (m) (T) *
    • Binary Star Two small closely mounted bulbs simulate resolution problems. (m) (T+) **
    • Spiral Galaxy Hand held Plexiglass model of spiral galaxy. (m) (T) *
    • Local Group of Galaxies Lights-up-in-the-dark three-dimensional model of the local group. (l) (T+) **
    • Astrobrella Umbrella decorated with the constellations. (m) (T) **
    • Relativity Grids. Looking at the principle of simultaneity and inertial frames using two parallel 2·D grids.
    • Bouncing Collision. A tennis/basketball combination is dropped to the floor...the resulting bounce models the implosive collision of a supernova. (m) (T)