Historical Astronomers Quiz

Ptolemy

140 AD

Contributions: Created the Geocentric Model; Used epicycles to try explain apparent retrograde motion

Copernicus

1540 AD

Contributions: Created the Heliocentric Model

Tycho Brahe

Late 1500’s AD

Contributions: Found a super nova (proved stars change); Created better tools; Took extremely accurate measurements

Johannes Kepler

1609 AD

Contributions: Found that Mars’ orbit was an ellipse; T²=R³

Galileo Galilei

1609-1610 AD

Contributions: Pointed a “Dutch Perspective Glass“ at the night sky and the sun; Discovered greater details of the moon; Sunspots; Venus has phases; Saturn has rings; The Milky-Way is made up of stars; Jupiter has moons

William Herschel

1770-1803 AD

Contributions: Student of Galileo, took his work when he died; Made larger telescope; Found 800 binary star systems; Found Uranus; Discovered infrared light

Annie Jump Cannon

1901 AD

Edward Pickering

Contributions: Catagorized 350,000 stars into 7 catagories; O B A F G K M (in that order)

Edwin Hubble

1922-1923 AD

Contributions: Discovered our universe is bigger than we thought; Discovered redshift (moving galaxies)

Geocentric System

A model that shows Earth is the center of our solar system and everything in it revolves around it

Heliocentric System

A model that shows the sun is the center of our solar system and everything in it revolves around it

Apparent Retrograde Motion

Caused by the differences in planets’ orbital speed; causes a planet to look as if it moves backward in the night sky before moving forward again (think mars)

Astronomical Unit

The average distance from the center of Earth to the center of the Sun

Orbital Period

The amount of time and object takes to compete a full orbit

Nebula

A cloud of gas and dust in space

Redshift

Similar to the doppler effect; moving light, increasing wavelengths (the wavelength is stretched so it moves to the red part of the spectrum)