Reading

Dust

Cosmic dust consists of tiny particles of solid material floating around in the space between the stars. It is not the same as the dust you find in your house but more like smoke with small particles varying sizes. Dust is important because we find lots of it around young stars. In fact it helps them to form, and it is also the raw material from which planets like the Earth are formed.

Gases

While hydrogen and helium make up most of the gases in interstellar space, tiny traces of other elements such as carbon, oxygen and iron also exist.

Asteroids

An asteroid is a large rock in outer space. Some can be very large, while others are as small as a grain of sand.

Comets

A small, frozen mass of dust and gas revolving around the sun. As a comet approaches and get close to the sun it starts emitting dust and gas. This debris forms a tail which is the image we are familiar with, the tail will always point away from the sun.

Planets

Planets are large natural objects that orbit, or travel around, stars. Planets we are familiar with include; Mars, Venus, Mercury, and Earth.

Moons

A moon is any natural satellite of a planet. The number of moons differs from planet to planet.

Stars

A star is a huge, bright ball of burning gas that is held together by gravity. Stars contain mostly hydrogen as well as helium and smaller amounts of other elements. The Sun is the closest star to Earth.

Solar Systems

A solar system includes the Sun and all the objects that orbit around it due to its gravity. These objects can include planets, moons, asteroids, comets, minor planets, and many other exciting objects.



According to the text, why is dust so important to a Galaxy?
Using evidence from the text explain the difference between an asteroid and a comet?
Based on the text identify what makes up a solar system?


Question 1: A star named Sirius appears as the brightest star in the night time sky, even though a star named Pollux actually gives off more light. Which of the following best explains why Sirius appears brighter than Pollux in our nighttime sky?

A. Sirius has a different color than Pollux does.

B. Sirius has different gases than Pollux does.

C. Sirius is closer to Earth than Pollux is.

D. Sirius is larger than Pollux is.



Explain your reasoning… Why?



Question 2: There are so many stars in the universe that it is hard to count them. Our Sun is a star that is located near the edge of a large group of stars shown here. What is this large group of stars called?

A. The Milky Way galaxy

B. The universe

C. The Whirlpool galaxy

D. The solar system

Explain your reasoning… Why?



Question 3: The Sun, like other stars, is a ball of hot, glowing gas. Which statement best describes the Sun?

A. The Sun is one of billions of stars in the universe.

B. The Sun is one of billions of stars in the solar system.

C. The Sun is at the center of the Milky Way galaxy.

D. The Sun is farther from Earth than any other star.



Explain your reasoning… Why?



Question 4: What items make up a galaxy?

A. Gas & Dust

B. Objects that orbit stars

C. Many Stars

D. All of the above



Explain your reasoning… Why?



Exit Ticket

What makes up a galaxy?

A. A group of stars that makes a pattern in the sky.

B. A large group of stars and planets.

C. Only the Sun and the planets around it.

D. Several universes located close together.