1. “Volume” is a measurement of the amount of space an object occupies. The sun has a whopping volume of about 1,409,272,569,059,860,000 cubic kilometers (338,102,469,632,763,000 cubic miles). The Earth has a volume of about 1,083,206,916,846 cubic kilometers (259,875,159,532 cubic miles).

    According to some astronomers, about 1.3 million Earths could fit inside the sun. According to other astronomers, only about 960,000 Earths could fit inside the sun.

    How can both of these facts be true?

  2. The mass and volume of the sun are so huge that some astronomers describe the solar system as “the sun plus some debris.” What are some examples of the “debris” of the solar system?

  3. The sun is a middle-aged star. It was born about 4.6 billion years ago, and has about 5 billion years left before it dies.

    Do you think the sun’s volume will get bigger or smaller as it gets older?

asteroid
Noun

irregularly shaped planetary body, ranging from 6 meters (20 feet) to 933 kilometers (580 miles) in diameter, orbiting the sun between Mars and Jupiter.

astronomy
Noun

the study of space beyond Earth's atmosphere.

comet
Noun

celestial object made up of ice, gas, and dust that orbits the sun and leaves a tail of debris.

dwarf planet
Noun

celestial body that is nearly spherical but does not meet other definitions for a planet.

Noun

our planet, the third from the Sun. The Earth is the only place in the known universe that supports life.

gas giant
Noun

one of the four enormous outermost planets in the solar system (Jupiter, Saturn, Neptune, Uranus), composed mostly of gases instead of rock. Also called a Jovian planet.

mass
Noun

measure of the amount of matter in a physical object.

Noun

natural satellite of a planet.

orbit
Noun

path of one object around a more massive object.

Noun

large, spherical celestial body that regularly rotates around a star.

red giant
Noun

"main sequence" star with huge surface area, low surface temperature, and reddish color.

solar system
Noun

the sun and the planets, asteroids, comets, and other bodies that orbit around it.

sphere
Noun

round object.

star
Noun

large ball of gas and plasma that radiates energy through nuclear fusion, such as the sun.

sun
Noun

star at the center of our solar system.

volume
Noun

space an object occupies.

white dwarf
Noun

small, dense "main sequence" star that has used up most of its nuclear fuel.