What is the orbital period of the Moon? - NASA
The sidereal period of the Moon is the time needed for it to return to the same position against the background of stars. The Moon appears to move completely around the celestial sphere once …
Where did the Moon come from? - NASA
The Condensation Theory: This theory proposes that the Moon and the Earth condensed individually from the nebula that formed the solar system, with the Moon formed in orbit around …
What are the phases of the Moon? - NASA
The Moon orbits Earth at an average distance of 382,400 kilometers. The lunar month is the 29.53 days it takes to go from one new moon to the next. During the lunar month, the Moon goes …
StarChild: The Dark Side of the Moon - NASA
The Dark Side of the Moon The phrase "dark side of the Moon" usually refers to the side of the Moon that we cannot see from Earth. The Moon takes about 29 days to orbit the Earth. It takes …
If you are on the Moon, does the Earth move in the sky? - NASA
Our Moon spins on its axis so that as it orbits the Earth, it always presents the same face to the Earth. As a result, when viewed from the Moon, the Earth will always remain in about the …
StarChild: The Dwarf Planet Eris - NASA
Eris does not clear out its orbit, so it did not meet one of the requirements. Consequently, it was placed in the newly created category of dwarf planet along with Pluto and Ceres, which also …
StarChild: The Moon - NASA
The Moon travels around Earth in an oval orbit at 3680 kilometers per hour. The Moon does not have an atmosphere, so temperatures range from -184 degrees Celsius during its night to 214 …
Jupiter's Moon, Io - NASA
Two of Jupiter's satellites, Europa and Ganymede, pull Io into an elliptical orbit around Jupiter. Differences in the strength of Jupiter's gravitational pull as the distance between the planet …
StarChild: The Moon - NASA
The Moon travels around the Earth in an oval shaped orbit. Scientists think the Moon was formed long ago when Earth collided with another space object. The collision may have caused a big …
StarChild: Glossary - NASA
DECAYING ORBIT A path around an object which decreases in size with time. For example, when a satellite enters a decaying orbit above Earth, its orbit size decreases to the point that it …