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NASA
Course: NASA > Unit 2
Lesson 1: Modeling the solar systemLunar eclipse
When the moon passes through the Earth's shadow, it causes the moon to look very unusual for a short period of time. This event is called a lunar eclipse, and it occurs roughly twice a year. Created by NASA.
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- is the moon bigger enough to cause solar eclipse while sun and earth both are bigger than moon(7 votes)
- The distance between Earth and Moon is smaller than the distance between Earth and Sun. This huge difference makes the Moon seems bigger and that's why it can cause a solar eclipse :)(9 votes)
- Will it damage your eyes if you stare directly at a Lunar Eclipse?(5 votes)
- No Lunar eclipse can not damage your eyes only solar eclipse does that(1 vote)
- Is this the only type of eclipse? What is the difference between a solar eclipse and a lunar eclipse?(8 votes)
- yes you are right this diagram may help us to understand.(1 vote)
- is it possible for a eclipse to happen with earth and mars(3 votes)
- Yes it is but we would not see a change. If you were a martian, though, you would be able an eclipse.(6 votes)
- when is the next Lunar Eclipse?(3 votes)
- The next Lunar Eclipse will be a Total Eclipse and occur on April 14 - 15th, 2014. It will be visible in Australia, Pacific and the Americas. This Lunar Eclipse Calendar is a listing of all Lunar Eclipses from 2014 to 2015.(3 votes)
- when is the red moon
and where is the best place to see it?(2 votes)- I guess the next one will be on Okt. the 8th.
Here have a look where to see it best, maybe you're lucky.
http://www.timeanddate.com/eclipse/lunar/2014-october-8(4 votes)
- At the very beginning of this video, where is the Earth and where is the Sun in relation to this view of the moon? is this our view of the moon from the Earth? And why does the moon appear to be backing up and then getting closer? and finally, can someone explain the whole thing about the moon's orbit being 5 degrees different than the Earth orbit (like, do they mean the Earth's orbit around the sun? and if the moon goes around the Earth, why would it go around the sun any different than the Earth does?) I'm writing a paper on eclipses for school, and I just can't get my head around it!
Thanks!(4 votes)- This is a link to an excellent diagram to explain the relative tilt of the lunar orbit.
https://userscontent2.emaze.com/images/b9b44673-867e-4074-8190-95df2a74c78c/8effc8fa4a003c118ff8056e855df44b.JPG
Just imagine to earth running along its track and the moon along the tilted track around the earth. Note that the earth itself spins on a tilted axis that points a certain direction in space and the high end and low end of the lunar orbit are oriented a certain way in the short term, but over 18.6 years that orientation precesses once so the high and low point come all the way around and back. Over a much longer period the direction the pole of the earth points in space also moves all the way around.(1 vote)
- How often do Lunar eclipses occur? Does it ever change?(3 votes)
- The lunar orbit is titled so that most of the time it is either above or below the earth's shadow and we get a lunar eclipse only when the full moon (directly opposite the sun relative to earth) occurs at the point in the lunar orbit where it is either passing from above or below (at the middle intersecting points or nodes). This only happens at two points in the sun, earth, moon system.
Here is a great diagram to visualize this:
https://userscontent2.emaze.com/images/b9b44673-867e-4074-8190-95df2a74c78c/8effc8fa4a003c118ff8056e855df44b.JPG
NOTE: The high end and low end of the lunar orbit are oriented a certain way in the short term, but over 18.6 years that orientation precesses once so the high and low point come all the way around and back so the time of year (defined by the orientation of the earth on it's axis which also changes over much longer periods of time) changes over the 18.6 years so you will get an eclipse occuring at one point in the year and then again at a point about opposite that, but the next year this will have shifted slightly till it comes all the way back round.(1 vote)
- Do other moons on other planets create eclipses too?(2 votes)
- What is a blue moon?(1 vote)
- it is a full moon that has happened the second time in one month. it is a rare event that occurs once every 2 to 3 years.(3 votes)
Video transcript
[music] [music] Narrator: If you looked at the moon over the course of a few weeks, you'd probably notice that it looks slightly different every day. The change in its shadow is based on where the moon is in its orbit. We call this cycle the phases of the moon, and it occurs roughly once a month. At least twice a year, however, something quite different happens. The moon passes through the shadow cast by the Earth, causing it to look extremely unusual for a short period of time. From the earth, the moon will appear to darken and turn a deep red before eventually returning to normal. This is called a lunar eclipse. If we were to look at what happens from space during an eclipse, it would go something like this. First, the moon passes through what's called the penumbra, where the sun's light is only partially obscured. This results in only a slight darkening of the moon. As the moon continues along its path, however, it enters what's called the umbra, where all direct light from the sun is blocked. But if the sun is blocked, why does the moon turn red? When light from the sun goes by the side of the Earth, it passes through a long and thick layer of Earth's atmosphere. Shorter wavelengths of sunlight, like blue, are scattered by the atmosphere, so by the time the light has finished its trip to the moon, more of the longer wavelengths, like red, are left over. On the Earth, the same thing happens at sunset as the ground you stand on gradually passes into night. As the eclipse ends, the moon leaves the umbra, returns to its normal color, and then leaves then penumbra, brightening and resuming its original cycle. Overall, the whole process lasts only from a few minutes to a few hours, so you'll have to be quick if you want to see it. But, as long as you're willing to stay awake, you'll catch the moon as you won't see it too often. [music, beeping] [music, beeping] [music] [silence]