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![]() Why aren't there eclipses at every full and new moon? http://earthsky.org/space/why-isnt-t...comment-page-1 There's not an eclipse at every new and full moon, but there are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. At such times, Earth's shadow falls on the full moon, causing a lunar eclipse. A solar eclipse happens at the opposite phase of the moon - new moon - when the moon passes between the sun and Earth. Why aren't there eclipses at every full and new moon? The moon takes about a month to orbit around the Earth. If the moon orbited in the same plane as the ecliptic - Earth's orbital plane - we would have two eclipses every month. There'd be an eclipse of the moon at every full moon. And, two weeks later, there'd be an eclipse of the sun at new moon for a total of at least 24 eclipses every year. But the moon's orbit is inclined to Earth's orbit by about 5 degrees. Twice a month the moon intersects the ecliptic - Earth's orbital plane - at points called nodes. If the moon is going from south to north in its orbit, it's called an ascending node. If the moon is going form north to south, it's a descending node. If the full moon or new moon is appreciably close to one of these nodes, then an eclipse is not only possible - but inevitable. The video below explains an eclipse when the new moon and full moon are aligned with the lunar nodes. Relative to the moon's phases, however, the nodes move about 30o westward (clockwise) each month. Hence, the new moon and full moon won't realign with the nodes again for nearly another six months. There might be some unfamiliar words in this video, including ecliptic and node. The ecliptic is the plane of Earth's orbit around the sun. The moon's oribt is inclined to the plane of the ecliptic. The nodes are the two points every month where the moon's orbit and the ecliptic intersect. Even though the moon's orbit is inclined to that of Earth - and even though there's not an eclipse with every full and new moon - there are more eclipses than you might think. There are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. All are marvelous to behold - a reminder that we live on a planet - a chance to experience falling in line with great worlds in space! |
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On Nov 29, 12:12*pm, "a425couple" wrote:
Why aren't there eclipses at every full and new moon?http://earthsky.org/space/why-isnt-t...ry-full-moon/c... There's not an eclipse at every new and full moon, but there are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. At such times, Earth's shadow falls on the full moon, causing a lunar eclipse. A solar eclipse happens at the opposite phase of the moon - new moon - when the moon passes between the sun and Earth. Why aren't there eclipses at every full and new moon? The moon takes about a month to orbit around the Earth. If the moon orbited in the same plane as the ecliptic - Earth's orbital plane - we would have two eclipses every month. There'd be an eclipse of the moon at every full moon. And, two weeks later, there'd be an eclipse of the sun at new moon for a total of at least 24 eclipses every year. But the moon's orbit is inclined to Earth's orbit by about 5 degrees. Twice a month the moon intersects the ecliptic - Earth's orbital plane - at points called nodes. If the moon is going from south to north in its orbit, it's called an ascending node. If the moon is going form north to south, it's a descending node. If the full moon or new moon is appreciably close to one of these nodes, then an eclipse is not only possible - but inevitable. The video below explains an eclipse when the new moon and full moon are aligned with the lunar nodes. Relative to the moon's phases, however, the nodes move about 30o westward (clockwise) each month. Hence, the new moon and full moon won't realign with the nodes again for nearly another six months. There might be some unfamiliar words in this video, including ecliptic and node. The ecliptic is the plane of Earth's orbit around the sun. The moon's oribt is inclined to the plane of the ecliptic. The nodes are the two points every month where the moon's orbit and the ecliptic intersect. Even though the moon's orbit is inclined to that of Earth - and even though there's not an eclipse with every full and new moon - there are more eclipses than you might think. There are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. All are marvelous to behold - a reminder that we live on a planet - a chance to experience falling in line with great worlds in space! What are the odds for a planet to have a moon to create a percise total eclpse such as Earth has? And how long will we keep having such a nice fit? Does Jupiter have any? None of the other planets have this luck. TreBert |
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On Nov 29, 11:20*am, "G=EMC^2" wrote:
On Nov 29, 12:12*pm, "a425couple" wrote: Why aren't there eclipses at every full and new moon?http://earthsky.org/space/why-isnt-t...ry-full-moon/c... There's not an eclipse at every new and full moon, but there are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. At such times, Earth's shadow falls on the full moon, causing a lunar eclipse. A solar eclipse happens at the opposite phase of the moon - new moon - when the moon passes between the sun and Earth. Why aren't there eclipses at every full and new moon? The moon takes about a month to orbit around the Earth. If the moon orbited in the same plane as the ecliptic - Earth's orbital plane - we would have two eclipses every month. There'd be an eclipse of the moon at every full moon. And, two weeks later, there'd be an eclipse of the sun at new moon for a total of at least 24 eclipses every year. But the moon's orbit is inclined to Earth's orbit by about 5 degrees. Twice a month the moon intersects the ecliptic - Earth's orbital plane - at points called nodes. If the moon is going from south to north in its orbit, it's called an ascending node. If the moon is going form north to south, it's a descending node. If the full moon or new moon is appreciably close to one of these nodes, then an eclipse is not only possible - but inevitable. The video below explains an eclipse when the new moon and full moon are aligned with the lunar nodes. Relative to the moon's phases, however, the nodes move about 30o westward (clockwise) each month. Hence, the new moon and full moon won't realign with the nodes again for nearly another six months. There might be some unfamiliar words in this video, including ecliptic and node. The ecliptic is the plane of Earth's orbit around the sun. The moon's oribt is inclined to the plane of the ecliptic. The nodes are the two points every month where the moon's orbit and the ecliptic intersect. Even though the moon's orbit is inclined to that of Earth - and even though there's not an eclipse with every full and new moon - there are more eclipses than you might think. There are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. All are marvelous to behold - a reminder that we live on a planet - a chance to experience falling in line with great worlds in space! What are the odds for a planet to have a moon to create a percise total eclpse such as Earth has? And how long will we keep having such a nice fit? *Does Jupiter have any? None of the other planets have this luck. * TreBert I saw that the Moon and Jupiter were together again last night. I wonder how often the Moon eclipses Jupiter? Double-A |
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"G=EMC^2" wrote in message...
- "a425couple" wrote: Why aren't there eclipses at every full and new moon? http://earthsky.org/space/why-isnt-t...ry-full-moon/c... There's not an eclipse at every new and full moon, but there are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. At such times, Earth's shadow falls on the full moon, causing a lunar eclipse. A solar eclipse happens at the opposite phase of the moon - new moon - when the moon passes between the sun and Earth. Why aren't there eclipses at every full and new moon? The moon takes about a month to orbit around the Earth. If the moon orbited in the same plane as the ecliptic - Earth's orbital plane - we would have two eclipses every month. There'd be an eclipse of the moon at every full moon. And, two weeks later, there'd be an eclipse of the sun at new moon for a total of at least 24 eclipses every year. But the moon's orbit is inclined to Earth's orbit by about 5 degrees. Twice a month the moon intersects the ecliptic - Earth's orbital plane - at points called nodes. If the moon is going from south to north in its orbit, it's called an ascending node. If the moon is going form north to south, it's a descending node. If the full moon or new moon is appreciably close to one of these nodes, then an eclipse is not only possible - but inevitable. The video below explains an eclipse when the new moon and full moon are aligned with the lunar nodes. Relative to the moon's phases, however, the nodes move about 30o westward (clockwise) each month. Hence, the new moon and full moon won't realign with the nodes again for nearly another six months. There might be some unfamiliar words in this video, including ecliptic and node. The ecliptic is the plane of Earth's orbit around the sun. The moon's oribt is inclined to the plane of the ecliptic. The nodes are the two points every month where the moon's orbit and the ecliptic intersect. Even though the moon's orbit is inclined to that of Earth - and even though there's not an eclipse with every full and new moon - there are more eclipses than you might think. There are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. All are marvelous to behold - a reminder that we live on a planet - a chance to experience falling in line with great worlds in space! -What are the odds for a planet to have a moon to create a percise -total eclpse such as Earth has? And how long will we keep having such -a nice fit? -Does Jupiter have any? None of the other planets have this luck. I'm assuming by "a percise total eclpse" you are thinking of the neat way the sizes & distances of the sun, earth & moon work out for our viewing *, and I agree it's neat, and I'd tend to think pretty long odds. (* without taking too much time for exact words, I'd say: For a total lunar eclipse, the complete shadow / shade of the earth totally covers ((but very little extra)) the moon. For a solar eclipse, the size of the moon is big enough to totally cover a fair hunk of earth, and create partial shade ((or a bite out of sun)) for a fair number of other viewers) Less 'ideal' viewing pleasure is described in: http://en.wikipedia.org/wiki/Moons_of_Mars "If viewed from the surface of Mars near its equator, full Phobos looks about one third as big as the Earth's full moon from Earth. It has an angular diameter of between 8' (rising) and 12' (overhead). It would look smaller when the observer is further away from the Martian equator, and is completely invisible (always beyond the horizon) from Mars' polar ice caps. Deimos looks more like a bright star or planet for an observer on Mars, only slightly bigger than Venus looks from Earth; it has an angular diameter of about 2'. The Sun's angular diameter as seen from Mars, by contrast, is about 21'. Thus there are no total solar eclipses on Mars, as the moons are far too small to completely cover the Sun. On the other hand, total lunar eclipses of Phobos are very common, happening almost every night.[12] See also Transit of Phobos from Mars and Transit of Deimos from Mars for eclipse-like events. The motions of Phobos and Deimos would appear very different from that of our own Moon. Speedy Phobos rises in the west, sets in the east, and rises again in just eleven hours, while Deimos, being only just outside synchronous orbit, rises as expected in the east but very slowly. Despite its 30 hour orbit, it takes 2.7 days to set in the west as it slowly falls behind the rotation of Mars, and has long again to rise." Meanwhile, for Jupiter, http://en.wikipedia.org/wiki/Moons_of_Jupiter "The planet Jupiter has 67 confirmed moons." But, only 4 have very significant size. (biggest of rest is 170 km.) Here are some fun related reads: Galileo Club, Part 2: Jupiter's Moons in Eclipse « 10 Minute Astronomy 10minuteastronomy.wordpress.com/.../galileo-club-part-2-jupiters-m... Nov 6, 2009 - Task #4 for the Astronomical League's Galileo Club: 4. 1612 - Jupiter's moons in eclipse: The objective is to show that in addition to the moons ... Jupiter's Moons to Vanish from View | Space.com http://www.space.com/7198-jupiter-mo...nish-view.html Aug 28, 2009 - ... the night of Sept. 2 when all four of Jupiter's largest moons will be hidden from our view. ... 3) they are within Jupiter's shadow (in eclipse). And (since I was reading it, I'll go ahead & post it) Saturn's moons: http://en.wikipedia.org/wiki/Moons_of_Saturn "The moons of Saturn are numerous and diverse, ranging from tiny moonlets less than 1 kilometer across, to the enormous Titan, which is larger than the planet Mercury. Saturn has 62 moons with confirmed orbits, Whoa! Here's an interesting read: http://curious.astro.cornell.edu/que...php?number=442 "Are there eclipses on other planets? " (snip - Mercury, Venus, Earth & Mars) "All four giant planets (Jupiter, Saturn, Uranus and Neptune) can experience eclipses, since they all have substantial moons and the Sun appears small from them. Eclipses are most common on Jupiter, because its moons orbit in the same plane with the Sun. " Have fun! |
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"Double-A" wrote in message...
- "G=EMC^2" wrote: - "a425couple" wrote: What are the odds for a planet to have a moon to create a percise total eclpse such as Earth has? And how long will we keep having such a nice fit? Does Jupiter have any? None of the other planets have this luck. TreBert -I saw that the Moon and Jupiter were together again last night. I -wonder how often the Moon eclipses Jupiter? I've often from morning to morning watched that pass also (moon moves ~ 12 degrees further east each day) and wondered. From the reading I've just done, & other response, I saw several cites on that topic of earth's moon from our sightline eclipsing Jupiter. Just Google moon jupiter eclipse for plenty of write ups & pictures (youtubes??). |
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On Nov 29, 2:20*pm, "G=EMC^2" wrote:
On Nov 29, 12:12*pm, "a425couple" wrote: Why aren't there eclipses at every full and new moon?http://earthsky.org/space/why-isnt-t...ry-full-moon/c... There's not an eclipse at every new and full moon, but there are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. A lunar eclipse happens when the Earth, sun and moon align in space, with Earth in the middle. At such times, Earth's shadow falls on the full moon, causing a lunar eclipse. A solar eclipse happens at the opposite phase of the moon - new moon - when the moon passes between the sun and Earth. Why aren't there eclipses at every full and new moon? The moon takes about a month to orbit around the Earth. If the moon orbited in the same plane as the ecliptic - Earth's orbital plane - we would have two eclipses every month. There'd be an eclipse of the moon at every full moon. And, two weeks later, there'd be an eclipse of the sun at new moon for a total of at least 24 eclipses every year. But the moon's orbit is inclined to Earth's orbit by about 5 degrees. Twice a month the moon intersects the ecliptic - Earth's orbital plane - at points called nodes. If the moon is going from south to north in its orbit, it's called an ascending node. If the moon is going form north to south, it's a descending node. If the full moon or new moon is appreciably close to one of these nodes, then an eclipse is not only possible - but inevitable. The video below explains an eclipse when the new moon and full moon are aligned with the lunar nodes. Relative to the moon's phases, however, the nodes move about 30o westward (clockwise) each month. Hence, the new moon and full moon won't realign with the nodes again for nearly another six months. There might be some unfamiliar words in this video, including ecliptic and node. The ecliptic is the plane of Earth's orbit around the sun. The moon's oribt is inclined to the plane of the ecliptic. The nodes are the two points every month where the moon's orbit and the ecliptic intersect. Even though the moon's orbit is inclined to that of Earth - and even though there's not an eclipse with every full and new moon - there are more eclipses than you might think. There are from four to seven eclipses every year. Some are lunar, some are solar, some are total, and some are partial. All are marvelous to behold - a reminder that we live on a planet - a chance to experience falling in line with great worlds in space! What are the odds for a planet to have a moon to create a percise total eclpse such as Earth has? And how long will we keep having such a nice fit? *Does Jupiter have any? None of the other planets have this luck. * TreBert Put a quarter coin at arms length and you created a coronagraph,and you can see the sun's corona.Where smoked glasses PLEASE Earth's shadow on the moon proves the Earth is round.TreBert |
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On Nov 29, 7:58*pm, "a425couple" wrote:
"Double-A" wrote in message... - "G=EMC^2" wrote: - *"a425couple" wrote: What are the odds for a planet to have a moon to create a percise total eclpse such as Earth has? And how long will we keep having such a nice fit? Does Jupiter have any? None of the other planets have this luck. TreBert -I saw that the Moon and Jupiter were together again last night. *I -wonder how often the Moon eclipses Jupiter? I've often from morning to morning watched that pass also (moon moves ~ 12 degrees further east each day) and wondered. From the reading I've just done, & other response, I saw several cites on that topic of earth's moon from our sightline eclipsing Jupiter. Just Google moon jupiter eclipse for plenty of write ups & pictures (youtubes??). http://ciel.science-et-vie.com/en/ob...es-jupiter-277 Another term: Moon occults jupiter. http://www.universetoday.com/96301/s...cults-jupiter/ Double-A |
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THAT METHOD IS BULL****!
ALL YOU PROVE IS HOW MANY MORONS THERE ARE HERE! Saul Levy On Sat, 1 Dec 2012 06:24:01 -0800 (PST), "G=EMC^2" wrote: Put a quarter coin at arms length and you created a coronagraph,and you can see the sun's corona.Where smoked glasses PLEASE Earth's shadow on the moon proves the Earth is round.TreBert |
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On Dec 1, 10:30*pm, wrote:
THAT METHOD IS BULL****! ALL YOU PROVE IS HOW MANY MORONS THERE ARE HERE! Saul Levy On Sat, 1 Dec 2012 06:24:01 -0800 (PST), "G=EMC^2" wrote: Put a quarter coin at arms length and you created a coronagraph,and you can see the sun's corona.Where smoked glasses PLEASE * Earth's shadow on the moon proves the Earth is round.TreBert Thanks for that site. Earth's moon proves Earth has all the right stuff for life. Sun and moon both the size of a coin. I would love to know the odds of that. It could be a million to one?? TeBert |
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