Astronomy Midterm

Which ancient society was the first to use math with Astronomy?

Greeks

One AU is equal to how many miles?

93 million miles

The distance between the Earth and the Sun is characterized by what unit?

AU

By how many degrees is Earth tilted?

23.5

What did Eudoxus create?

The model of 27 nested spheres

What did Aristotle believe about Earth?

That it was imperfect and unchangeable

What did Aristotle believe about orbits?

That they were perfect spheres

Who first calculated Earth’s radius?

Eratosthenes

Epicycles

Small circles within a larger circle

Who disproved Epicycles?

Copernicus

Who created the heliocentric universe?

Copernicus

Which astronomer added to Copernican thinking?

Galileo

Who discovered the moons of Jupiter and the Rings of Saturn?

Galileo

Who observed Venus’ phases?

Galileo

Who believed in a modified geocentric model?

Tycho Brahe

What principles did Johannes Kepler abandon?

Circular and uniform motion

Was Johannes Kepler a heliocentrist?

Yes

1st law of Planetary Motion

Planets have elliptical orbits

2nd law of Planetary Motion

Planets move the same distance relative to time

3rd law of Planetary Motion

Orbital period squared is proportional to average distance from Sun cubed

P represents?

Orbital period

Newton’s 1st Law

Body at rest won’t move unless acted upon

Newton’s 2nd Law

Acceleration is proportional to unbalanced force

Newton’s 3rd Law

Equal and opposite reaction

Variable star

Stars which change from bright to dim

Cepheid variable period-luminosity relationship

The brighter the star is overall, the longer the period of luminosity

Who discovered the cepheid variable relationship?

Henrietta Swan Leavitt

Who classified stellar spectra?

Annie Jump Cannon

Initial conditions of the solar system

Cold molecular clouds of hydrogen and helium

What causes clouds to rotate?

Cloud collapse

Accretion

Formation of big things from small things

Jovian gas planets were formed when

Leftover gas was blown by solar winds

Why is Mercury’s crust the way it is?

Crumpled and damaged due to cooling and bombardment

Does Mercury have seismic activity?

Yes

Does Mercury have a magnetic field?

Yes

What is the morning star planet?

Venus

Which planet has lava domes and shield volcanoes?

Venus

Venus’ atmosphere

Dense CO2 and acid clouds

Does Venus have a magnetic field?

No

Which other planet has similar seasons and days to Earth?

Mars

Which side of Mars may have once been an ocean?

The Northern Hemisphere

Mars’ core

Non-metallic or non-liquid

Jupiter’s atmosphere

90% Hydrogen and 10% Helium

Which two planets have light and dark atmospheric belts?

Jupiter and Saturn

Jupiter’s composition

Hydrogen and Helium

Saturn composition

Hydrogen, helium, methane, and ammonia

How many cloud layers does Saturn have?

3