Since earth is not a perfect sphere, during a lunar eclipse why can't we see its shadow as elliptical?
396433
While the Earth is not perfectly round, the difference is so small, much less than 1%, that you cannot notice it at all just by looking.
1080564
ok...this is a little complicated. when there is a solar eclipse, only a certain section of the earth can see it because of the angle of light from the sun going around the moon. i cant remember the terminology, but if you look it up on the internet, you could probably find it.
144341
You are right.\n\nAn astronaut standing on the "earth" side of the moon during a "new moon" might see the small shadow of the earth moving across the surface of the earth -- a partial eclipse of the earth.\n\nNot total eclipse of the earth by the moon's shadow is possible because the moon is too small.\n\nThe oddball thing is that by coincidence the moon appears to be the same size in the earth's sky as the sun. about one finger tip at arms' length which is about half a degree of angle.
410954
The Earth is round.\nObviously at lower latitudes you view the moon from a different angle than what you would at higher latitudes.\nSo that at the equater the moon when rising would look like a bowl from that angle in that phase.
354795
It is a lot easier to demonstrate this with graphics than trying to explain it in text.  You can likely find a good diagram if you go to google it.\n\nFirst imagine the sun.  Now imagine the earth revolving around the sun.  Keep in mind that the earth and the sun are both extremely small compared to the distance that the earth is from the sun.  this means it's like two specks of dust revolving around each other in a basketball court, to give some perspective.\n\nNow imagine the moon revolving around the earth but ignoring gravitational effects of the sun (for simplicity).  Since the earth is so small compared to these revolutions, imagine that the earth very rarely blocks the light from the sun shining on the moon.\n\nNow when you observe the moon, if it is roughly between you and the sun, it is the backside of the moon that is lit.  This means the only part of the moon that you see is the shadow - or the new moon.  If when you observe the moon it is roughly behind the earth, you get to see the part of the moon that is being shined on by the sun - a full moon.  Since the moon revolves around the earth at a rate different from the rate at which the earth spins on its axis, the moon will change its orientation to give us our progression through the phases of the moon.\n\nJust an additional bit - eclipses are those rare times when the earth's shadow actually DOES hit the moon.. making what would've been a full moon into something else (a lunar eclipse).  The more commonly noticed (due to the drastic change in light during the day :D ) solar eclipses are when the moon directly blocks the sun's light from the earth.  These occur at regular intervals over series' of years.
700051
1. Eclipses, and lunar phases. \n2. The other "celestial" bodies, like the sun, moon and planets also appear round. One might assume, that the earth might be also.  \n3. Gravitational laws based on the earth being a certain shape and size, predict movement, etc. \n4. The stars in the southern hemisphere are  different than in the northern hemisphere.\nIf the earth was flat, one should be able to see the all of the stars at least some of the time. \n5. Sailors regularly circumnavagate the earth.\n6. Planes regularly fly around the world.\n7. The seasons and the climatic zones are hard to explain otherwise. \n8. The coreolis forces of hurricanes.\n\nOne can use scientific method to prove all of these and come up with conclusions for an earth that is somewhat round in shape, if one isnt lucky enough to see it from space, and believe it with your own eyes.
589478
No. The Earth is too small from the vantage point of other planets and too big from the Moon to cause an eclipse.
296979
The Moon is self explanatory, just look skyward at a full Moon to see it is spherical. The Earth takes some proving, but all you need is a space photo or two for people to get the idea. Oh, and the Earth is technically an oblate spheroid.
968800
It is the shadow of the Earth or rather, the part you see is the part that is not in the shadow of the Earth.\n\nThe shape the moon appears depends on its position relative to the Earth and the Sun. Depending on the timing, the shadow the Earth casts on the moon will change.\n\nSince the orbits of the moon and earth are constant, astronomers thousands of years ago have been able to predict the shape of the moon depending on the date.
310923
It's orbit is closer to a circle than any other with an eccentricity of less that 1%. It also has a retrograde motion (it rotates from east to west instead of west to east). It always shows the same face to earth in the same way the moon does.
427739
Earth's shadow, it is called a lunar eclipse. \n\nWhen the Earth crosses between the Moon and the Sun in exact alignment, a total lunar eclipse occurs.
396469
The path of the light (or shadow) is unrelated to the gravity.  Gravity of both bodies (sun and moon) is acting on the whole Earth, not just the area where the eclipse is seen, so earthquakes would not be related to the eclipse.  BTW: Tidal forces of the sun and moon happen all the time and alignments and oppositions will create extreme pulls.
88690
In order for an eclipse to occur, there has to be a very specific line up of the Sun, Moon, and Earth.  It's pretty hard to get that line-up to happen.  You see, the moon's orbit is tilted to the earth's orbital plane by about 5 degrees.  That may not seem like a lot, but its enough for the moon's shadow to miss the earth almost all of the time.
539515
Moses and Campbelp have it right--the fluorescent light is closer and of larger apparent size (especially if it is a long tube!).  The sun's shadows are not perfectly sharp because it has some size.  This is the cause of the "penumbral" lunar eclipse, when the moon dims but is not fully eclipsed, as it passes through the dim but not dark portion of the Earth's shadow (the penumbra--the darkest part of a shadow is the umbra).
350565
Lunar: the earth gets between the sun and the moon and so it projects its shadow on the moon and it dissapears for a moment.\nSolar: The moo gets between the earth and the sun and you stop seeing the sun or a part of it during some moments, a complete solar eclipse you still see a ring of sun around the moon due to size difference. This doesn't happen on the lunar one as the projected shadow of the earth is much bigger than the moon (and the earth itself) so the moon can disappear for several minutes...
75356
Light from the Sun is reflected off of the Earth  onto the Moon. Some of this light is then reflected off of the Moon back towards the Earth.  Because of this we see part of the Moon illuminated by the Sun and the rest of the Moon dimly illuminated by this doubly reflected light (which we call earthshine). Each time light reflects off a surface (like a planet), it gets dimmer because some of the light is absorbed by the reflecting surface. This means that earthshine is dimmer than moonlight because earthshine is sunlight that has been reflected twice and moonlight is sunlight that has been reflected only once (off the surface of the moon). In addition, the reflectivity of the moon (its "albedo") is less than that of the Earth, which makes earthshine even dimmer. \n\nHave you ever wondered why the moon is more orange or yellow in color when it first rises at night? This effect is caused by the atmosphere of the earth. The reason for the orange color is due to the scattering of light by the atmosphere. When the moon is near the horizon, the moonlight must pass through much more atmosphere than when the moon is directly overhead. By the time the moonlight reaches your eyes, the blue, green, and purple pieces of visible light have been scattered away by air molecules. That's why you only see yellow, orange, or red.
956093
The lunar plane (the imaginary circle around the earth in which the moon revolves) is not in line with earth's view of the sun, hence solar eclipses, especially total solar eclipses, are rare events.\n\nBoth types of eclipses have comparative frequencies, but you're more likely to be able to see a lunar eclipse. The reason is, the earth's shadow is so much larger than the moon, and amost anyone on the night side of the earth will be able to see the lunar eclipse.\n\nCompare this to the shadow of the moon, which is really small when it falls on the earth, so only a limited number of people in a small area can see it.