Ask an Astronomer FOR KIDS! - Stars

What is a star?
What are stars made of?
How many stars can you see at night?
How many stars are there?
What is the closest star to Earth?
Is the sun the largest star?
Why do stars twinkle?
What are constellations?
Why do stars only come out at night?
Why are some stars bright and others dim?
Will we ever travel to the stars?
How far away are the stars?