NASA PADLET PAGE by Jason Luo

Shouldn't we get eclipses every month? Why don't we? #huh

jasonluo2002 — 2015-04-03 15:14:41 UTC

The moon doesn't orbit on the same plane that Earth orbits the sun, because if it was, there would be a complete eclipse every month. The Earth's axis is tilted at a 23.5° angle, pointed towards Polaris. The moon's orbit is almost aligned with the spin of Earth. This explains why there aren't eclipses every month. Here is the moon as it orbits Earth.

What are the umbra and penumbra of an eclipse? #noclue #scienceRULES

shi_will_2003 — 2015-04-03 15:52:24 UTC

During of an eclipse, the umbra is the part where sunlight is completely blocked out, while the penumbra is where the sunlight is only partially. In a solar eclipse, the umbra is the spot on Earth directly under the moon. In the umbra, you see a total eclipse, but in the penumbra, you only see a partial eclipse.

How do moon phases work? Where are all the E, M, and S during each moon phase? Why does the moon always look different? #somanyquestionssolittletime

harvardwang2 — 2015-04-03 15:56:41 UTC

Moon phases occur because of the moon's orbit around Earth. At different times different parts of the moon are visible from Earth depending on where sunlight hits the moon. The moon always looks different because it is constantly moving around Earth. The picture below shows where each the Earth, Moon, and Sun are during each moon phase.

Shouldn't we get eclipses every month? Why don't we? #huh(continued)

jasonluo2002 — 2015-04-04 21:11:42 UTC

How does an eclipse occur? How often do they occur? When is the next one? #wishihadseenthis #jealous

jasonluo2002 — 2015-04-04 21:25:30 UTC

Solar eclipses occur when the moon moves between the earth and the sun. Lunar eclipses are when the moon moves behind the shadow of the earth. There is no set pattern to how often eclipses occur, but if you know how, then you can predict when. The next solar eclipse will be on August 21, 2017, and the next lunar eclipse will be on September 28, 2015.

Why do we only see one side of the moon? #darkside

jasonluo2002 — 2015-04-04 21:29:04 UTC

We only see one side of the moon because the moon rotates on its axis about same rate it orbits earth. This video shows how when the moon rotates, you always see the same side from earth.

What are all those holes on the moon & how did they get there? #cool

jasonluo2002 — 2015-04-07 12:10:18 UTC

The holes on the moon are craters. Craters are indent in any surface, in this case, the moon. Many craters are believed to have formed 300-400 million years ago when meteors and other objects crashed into the moon. The moon is able to have so many craters because it has no atmosphere. When meteors hit Earth, they would have burned up in the mesosphere, so Earth does not have many craters.

Which moon phase is that above? #crescent

jasonluo2002 — 2015-04-11 23:23:01 UTC

The moon phase is a waxing crescent moon. You can tell because the light is on the right side, so it is waxing, and it is shaped like a crescent, which is less than a first quarter moon, and greater than a new moon.