Why does the Sun rise in the east and set in the west? - NASA
Answer: The Sun, the Moon, the planets, and the stars all rise in the east and set in the west. And that's because Earth spins -- toward the east. For a moment, let us ignore Earth's orbit around the Sun (as well as the Sun's and solar system's revolution around the center of the Galaxy, and even the Galaxy's journey through the universe).
What causes a "falling star"? - NASA
A "falling star" or a "shooting star" has nothing at all to do with a star! These amazing streaks of light you can sometimes see in the night sky are caused by tiny bits of dust and rock called meteoroids falling into the Earth's atmosphere and burning up. The short-lived trail of light the burning meteoroid produces is called a meteor.
Why is space black? - NASA
At night, when that part of Earth is facing away from the Sun, space looks black because there is no nearby bright source of light, like the Sun, to be scattered. If you were on the Moon, which has no atmosphere, the sky would be black both night and day. You can see this in photographs taken during the Apollo Moon landings.
Why do stars twinkle? - NASA
The movement of air (sometimes called turbulence) in the atmosphere of Earth causes the starlight to get slightly bent as it travels from the distant star through the atmosphere down to us on the ground. This means that some of the light reaches us directly and some gets bent slightly away. To our eyes, this makes the star seem to twinkle.
What makes stars shine - NASA
What makes the Sun shine? Answer: The simple answer is that deep inside the core of the Sun, enough protons can collide into each other with enough speed that they stick together to form a helium nucleus and generate a tremendous amount of energy at the same time. This process is called nuclear fusion.
Why is the crescent moon sometimes lit on the bottom? - NASA
Question: Why is the crescent Moon sometimes lit on the bottom? Answer: A careful observer will certainly notice that over the period of months, the crescent of the Moon does indeed seem to go from being lit on the "bottom" of the Moon to being lit on the side of the Moon. So what is happening to make the Moon look different? It is all a result ...
StarChild: The planet Earth - NASA
It has an atmosphere made up of many different gases, but mainly it is nitrogen and oxygen. The atmosphere gives us air to breathe. We live on the planet Earth. The Earth orbits around the Sun. It takes one year to go around the Sun one complete time. The Earth also rotates, or spins, on its axis. It takes one day to spin around one complete time.
The Phases of the Moon - NASA
The Phases of the Moon. visible. Return to the StarChild Main Page. Go to Imagine the Universe! (A site for ages 14 and up.) High Energy Astrophysics Science Archive Research Center (HEASARC) Astrophysics Science Division (ASD) NASA/ GSFC. The StarChild Team. Acknowledgments. Dr. Laura A. Whitlock.
When is Earth closest to the Sun? - NASA
Answer: On January 4, 2003, our Earth made its closest approach to the Sun for the year-- an event astronomers call perihelion. At perihelion, the Earth is about 147.5 million km away from the Sun. (At the greatest separation, the two are about 152.6 million km apart - which will occur this year on July 4.) Relatively speaking, Earth's distance ...
StarChild Question of the Month for April 2001 - NASA
The Moon appears to move completely around the celestial sphere once in about 27.3 days as observed from the Earth. This is called a sidereal month. It represents the orbital period of the Moon around the Earth. Measuring the motion of the Moon around the Earth relative to the Sun leads us to what is called the synodic (pronounced si-nod-ik ...