an attempt to find out about something

• model

• investigation

• explanation

• evidence

a scientist who studies stars, planets, and other objects in the universe

• astronomer

• constellation

• gravity

• model

to move in a regular path around something

• evidence

• model

• day

• orbit

a period of time that is 24 hours long and includes daytime and nighttime

• orbit

• day

• data

• gravity

information that supports an answer to a question

• data

• model

• evidence

• investigation

an arrangement of stars as seen from Earth

• astronomer

• orbit

• costellation

• gravity

observations or measurements recorded in an investigation

• data

• day

• explanation

• criteria

something scientists make to answer questions about the real world

• model

• data

• criteria

• explanation

a description of how something works or why something happens

• investigation

• evidence

• data

• explanation

 the pull between Earth and other objects, which acts even without touching

• orbit

• model

• day

• gravity