31. Sun is made of 73.46%:
32. What is the distance to the Moon?
33. The distance that light travels in vacuum in one Julian year is called:
34. What is the current angle of the tilt of the Earth's axis?
35. What is the rotation period of Earth?
36. Which is the farthest planet in our solar system?
37. Which is the closest planet to earth?
38. What is a Nebula?
A black hole
A cloud of gas and dust
A dead star
39. How long is a solar cycle?
40. How far is Uranus from Sun?