The first accurate measurement of the size of Earth was made by ____.

Hipparchus was best known for his ____.

The apparent westward movement of a planet against the background of stars is called ____.

According to the ancients, the stars traveled around Earth on the transparent, hollow ____.

One astronomical unit (AU) averages about ____.

A measure of the total amount of matter an object contains is called ____.

Using Tycho Brahe’s data, which scientist proposed three laws of planetary motion?

The first early astronomer to propose a sun-centered solar system was ____.

Which scientist discovered that Venus has phases, just like the moon?

The force that gravity exerts on an object is called ____.

What is the shape of a planet’s orbit?

Which law states that each planet revolves so that an imaginary line connecting it to the sun sweeps over equal areas in equal time intervals?

Which scientist determined the nature of the forces that keep the planets in their orbits?

Which scientist was the first to use the telescope in astronomy?

The true shape of planetary orbits was discovered by ____.

Which astronomer spent 20 years plotting the positions of the planets?

Earth is closest to the sun at a point called ____.

Earth’s axis slowly but continuously points in different directions, a movement known as ____.

What movement of Earth is responsible for night and day?

The turning or spinning of a body on its axis is known as ____.

The moon is closest to Earth at ____.

What occurs when the moon casts its shadow on Earth?

Round depressions on the moon’s surface are called ____.

The oldest features on the moon are ____.

How old is the moon?

Which of the following is NOT a Jovian planet?

Which of the following is NOT a terrestrial planet?

The most obvious difference between the terrestrial and the Jovian planets is ____.

The formation of the solar system from a huge cloud of dust and gases is called the ____.

Which planet shows evidence of water erosion?

Which planet has a cratered surface similar to Earth’s moon?

The planet with the greatest temperature extremes is ____.

Which planet has a dense carbon dioxide atmosphere and high surface temperatures?

On which thickly clouded planet has radar mapping revealed a varied topography consisting of plains, highlands, and thousands of volcanic structures?

How many known satellites does Mars have?

The atmosphere of Venus is composed primarily of ____.

Mons Olympus, a volcano the size of Ohio, is found on ____.

Which planet has a greater mass than the combined mass of all the remaining planets and their moons?

Which of Jupiter’s moons is volcanically active?

Which planet might best be described as a large, dirty iceball?

Which planet is associated with the Great Dark Spot?

What is the smallest planet?

Which planet’s axis of rotation lies nearly parallel with the plane of its orbit?

According to a relatively recent discovery, which planet has one satellite?

The relatively small, rocky bodies generally found orbiting between Mars and Jupiter are known as ____.

A comet’s tail always points ____.

The glowing head of a comet is known as the ____.

Comets with short orbital periods are located in what region?

The small particles that produce a streak of light upon entering Earth’s atmosphere are called ____.

The remains of extraterrestrial particles that are found on Earth’s surface are called ____.

Terrestrial particles that are found on Earth’s surface are called ____.

Which of the following is NOT a form of electromagnetic radiation?

Which color has the longest wavelength?

Gamma rays, X-rays, visible light, and radio waves are all types of ____.

The fact that light can exert a pressure on matter suggests that it is made of particles called ____.

The energy of a photon is related to its ____.

A typical incandescent light bulb produces a(n) ____.

Which famous scientist unknowingly founded the field of spectroscopy?

Which type of spectrum can be produced by a solid, liquid, or gas?

Which of the following refers to the change in wavelength that occurs when an object moves toward or away from a source?

A refracting telescope produces an image using a(n) ____.

A reflecting telescope produces an image using a(n) ____.

Which famous scientist first used a telescope for astronomical observations?

When several radio telescopes are wired together, the resulting network is called a radio ____.

The magnification of a telescope is changed by changing the ____.

The James Webb Space Telescope will study ____.

What was the first space telescope built by NASA?

The layer of the sun that radiates most of the light that reaches Earth is the ____.

The outermost layer of the sun is called the ____.

Which part of the sun lies directly above the visible “surface” of the sun?

The sun’s surface has a grainy texture produced by numerous bright markings called ____.

The thin red rim seen around the sun during a total solar eclipse is called the ____.

The sun’s surface is made up mostly of ____.

Streams of electrons and protons that shoot out from the sun’s corona make up the solar ____.

What are the most explosive events that occur on the sun?

The product of nuclear fusion is ____.

The source of the sun’s energy is ____.

In the equation E = mc^2, what does c represent?