R is for…
NASA’s Picture Dictionary
Check out what R stands for…
Radar
A device that sends out radio waves and picks them up again after the waves strike another object and bounce back.
Sentences:
Radar is used to help predict weather and measure waves of the ocean.
Police officers can tell how fast a car is going by using a radar device.
Related Links:
Birds and Radar
Rainbow
An arc or circle of colors that appears in the sky opposite the sun. A rainbow is caused by the sunlight shining through raindrops, spray or mist.
Sentences:
The colors red, orange, yellow, green, blue, indigo and violet make up a rainbow.
A rainbow is created when sunlight passes through raindrops.
Rehydrate
To add water to a dried item, such as food.
Sentences:
Astronauts take freeze-dried food into space and rehydrate the food before eating.
When our bodies are thirsty, we must rehydrate ourselves by drinking water.
Remote Sensing
Studying an object without coming into direct contact with it.
Sentences:
Satellites are important tools used by NASA for remote sensing.
People taking pictures from hot air balloons were the first to use remote sensing.
Researcher
A person who studies to find out about a subject, usually to learn new facts or solve a problem.
Sentences:
NASA has researchers that study the weather.
Our teacher said that a good researcher could find answers to many problems.
Revolve
To circle around something or move in an orbit.
Sentences:
Earth revolves around the sun in 365 days, 5 hours, 59 minutes and 16 seconds.
The time a planet takes to revolve around the sun is called a year.
Robot
A machine that is built to do a certain job again and again, or to do work that might be dangerous for humans.
Sentences:
NASA uses robots to explore other planets.
Robots are used to paint new cars.
Related Links:
Robonaut 2 Video
Robonaut 2: Introduction
R2 on Space Station
Robotic Arm
A mechanical arm designed for grabbing, holding and moving objects.
Sentences:
The space station’s robotic arm helps astronauts lift large objects while in space.
Some factories use robotic arms to build cars.
Related Links:
Curiosity’s Robotic Arm
Robotics on the International Space Station
Dextre the Magnificent
Rocket
A vehicle used to launch people and objects into space.
Sentences:
NASA has used different rockets to launch humans and satellites into space.
A girl built a model rocket and tested it for her science project.
Related Links:
What is a Rocket? (Grades K-4)
What is a Rocket? (Grades 5-8)
Roman Numeral
A letter used as a number in the very old Roman number system.
- I equals 1
- V equals 5
- X equals 10
- L equals 50
- C equals 100
- D equals 500
- M equals 1,000
Sentences:
Some NASA patches have Roman numerals on them.
Until 1969, NASA only used Roman numerals for missions that were a success.
Rotate
To turn around in a circle; to spin.
Sentences:
Earth rotates on its axis once a day.
The second hand on the clock rotates faster than the other hands.
Related Links:
Watch Jupiter Rotate
Rover
A vehicle for exploring the surface of a planet or moon.
Sentences:
Spirit and Opportunity are the names of two NASA rovers that have explored Mars.
The rovers have taken some very cool pictures of Mars.
Related Links:
Draw a Rover and Helicopter on Mars
Pictures of Mars
