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 …

The Moon's different chemical composition could be explained if it formed elsewhere in the solar system, however, capture into the Moon's present orbit is very improbable. Something would …

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 …

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 …

Scientists believe that lava at one of the sites reaches a temperature of over 1700 degrees Celsius. This temperature is approximately 3 times the hottest surface temperature on …

The phases we see result from the angle the Moon makes with the Sun as viewed from Earth. The diagram below on the right is one you typically see in books. Don't let it confuse you. The …

We are moving at an average velocity of 828,000 km/hr. But even at that high rate, it still takes us about 230 million years to make one complete orbit around the Milky Way! The Milky Way is a …

The Moon should be held in front at arm's length and slightly elevated overhead. (Make sure the students understand that it is because of the Moon's slightly inclined orbit around Earth that …

Isaac Newton was the first person to realize that there must be a connection between the period of a pendulum and the period of a planet orbit. He realized that the pendulum bob was …

After Pluto and Eris, Makemake is the third largest dwarf planet. It takes this dwarf planet 310 Earth years to make one orbit around the Sun. At this time, no moons have been discovered in …