Vocabulary
The curved path a planet takes around the sun.
orbit
"The sun is in the center of a group of eight planets. All of these planets, including Earth, circle, or orbit, around the sun. The sun, planets, and other objects in space that orbit the sun are called the solar system. The word solar has the Latin root word sol, which means 'sun.' Everything in the solar system relates to the sun." What is the main idea of this passage?
The solar system is made up of the sun, planets, and other objects that all orbit the sun.
This astronaut was the first person to walk on the moon.
Neil Armstrong
How many planets are in our solar system?
Eight
"The stars in the night sky do not look like the sun. They do not look as big or as bright. But they are, in fact, very much alike. The stars in the night sky are big balls of hot gas, just like the sun. The night stars are much, much farther away from Earth than the sun. That is why they look like tiny specks of light." According to the text, why does the sun appear bigger and brighter than other stars?
The sun is the closest star to Earth. Other stars look small because they are much farther away.
A force that pulls objects toward one another.
gravity
"When you see the moon at night, it might look white. It might look gray or silver. Sometimes, it seems to shine and glow. But the moon does not give off light the way the sun does. The moon is a ball of rock that gives off no light of its own. It simply reflects light from the sun." What is the main idea of this passage?
The moon does not make its own light. It reflects light from the sun.
This astronomer built a telescope in 1609 and used it to discover four of Jupiter's moons.
Galileo
This planet is known for its large rings made of ice and dust.
Saturn
"When Earth rotates on its axis, it is tilted. At certain times of the year, one part of Earth is tilted toward the sun. The sunlight is more direct and it feels hotter. For people living on this part of Earth, it is summer. For people living on the part of Earth tilted away from the sun, there is less sunlight and it is winter. So, when it is summertime for us, there are people living on other parts of Earth where it is winter!" What detail from the text supports the idea that Earth's tilt causes the seasons?
When part of Earth tilts toward the sun, sunlight is more direct and it becomes summer. When it tilts away, there is less sunlight and it becomes winter.
An event that occurs when one object in space blocks sunlight from reaching another object.
eclipse
"Other kinds of space rocks called meteoroids are also found throughout the solar system. When a meteoroid enters Earth's atmosphere, we call it a meteor. Small pieces of the meteor burn brightly and look like a white trail across the sky when viewed from Earth. Sometimes people call this a 'shooting star.' A meteor shower is when many meteors can be seen falling in the sky on the same night. If a meteor doesn't fully burn up in the atmosphere, it falls to Earth and can make a large hole called a crater." What is the main idea of this passage?
There are different types of space rocks. When they enter Earth's atmosphere they become meteors, and if they land on Earth they are called meteorites.
This British scientist discovered the most famous comet in our solar system. The comet was named after him and can be seen from Earth with the naked eye every 76 years.
Edmund Halley
What is the difference between a meteor and a meteorite?
A meteor is a space rock that enters Earth's atmosphere and burns brightly. A meteorite is a meteor that does not fully burn up and lands on Earth.
"It was very expensive and took a lot of time to build and send spaceships into space. When Apollo 11 returned from space, it landed in the sea. It was not able to land safely on the ground, so this type of spacecraft always had to land in the sea. Once it landed in the sea, this kind of spacecraft could not be used again. In 1981, a reusable spacecraft, called a space shuttle, was built. It was able to fly up into space and then zoom back down to Earth. When it returned to Earth, the pilot was able to land the spacecraft on a runway almost like an airplane." What two details from the text show that the space shuttle was an improvement over earlier spacecraft?
The space shuttle could be reused and flown back into space again and again. It also landed on a runway instead of splashing into the sea.
atmosphere — Write your own definition based on what you learned in the unit.
A layer or blanket of gas that surrounds Earth or a planet.
"Remember that the sun is also a star. The stars in the night sky are big balls of hot gas, just like the sun. All stars are big balls of hot gas, but astronomers have discovered that stars differ in many ways. Stars can be different sizes and colors. Some stars are closer to Earth than others and some stars are hotter than others. Stars that are the hottest and closest to Earth appear brighter than other stars." What is the main idea of this passage?
All stars are made of hot gas like the sun, but they differ in size, color, brightness, and how close they are to Earth.
Mae Jemison applied to NASA twice. What happened the first time, and what did she accomplish the second time?
The first time she applied, NASA did not accept her. The second time she was accepted and became the first Black female astronaut in space.
Why does Mercury have a shorter year than Earth?
Mercury is the closest planet to the sun. The closer a planet is to the sun, the less time it needs to orbit. Mercury only takes 88 days compared to Earth's 365 days.
"There are other differences in space besides less gravity. Do you remember that the astronauts on the moon had to carry tanks of air for breathing? Another way outer space is different from Earth is that there is no air or oxygen at all in outer space. Since there is no air in space, you also do not hear sounds in outer space. It is also very cold in space. The astronauts must train many months before going into space so they know what to expect." Using text evidence, explain why astronauts cannot hear sounds in outer space.
The text states there is no air or oxygen in outer space. Since there is no air, sound cannot travel, making space completely silent.
weightlessness — Write your own definition based on what you learned in the unit.
having little or no weight, or the feeling of floating because the effects of gravity are not felt
"They suggested that long ago, the universe and everything in it was once a tiny ball. All of the stuff that makes the universe was squeezed together into one tiny space. Scientists think that everything began expanding outward about 14 billion years ago. All the matter in the universe exploded out at once. That is why the event is called the Big Bang. Over time the matter began to cool, and gravity was able to hold little bits of matter together. These little bits came together and became the first stars and galaxies." What is the main idea of this passage?
The Big Bang Theory states that all matter in the universe started as one tiny ball, exploded outward about 14 billion years ago, and eventually cooled and formed the stars and galaxies we have today.
Copernicus had an idea that most people at the time strongly disagreed with. What was his idea and why did so many people disagree with it?
Copernicus believed Earth orbited the sun, not the other way around. This was controversial because people had believed for thousands of years that Earth was the center of the universe, and the church's teachings were based on that belief.
Name all eight planets in order from closest to farthest from the sun.
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
"Hubble's observation led scientists to offer explanations of how the solar system started. There are many explanations about how the universe came to be. One idea is known as the Big Bang Theory. A theory in science tries to explain how something happened based on evidence, or facts and information. Scientists are continuing to look into space for more clues about the Big Bang. There is still a lot to learn about the early universe. Scientists sometimes make minor changes to the Big Bang Theory to match what they have learned." Using evidence from the text, explain what the word theory means in science and why scientists keep updating the Big Bang Theory.
The text says a theory is a suggested explanation based on evidence or facts. Scientists keep updating the Big Bang Theory because they continue finding new clues about the early universe and adjust the theory to match what they learn.