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Fraser
2007-Jul-30, 04:00 PM
Consider the following: we've got tides here on Earth, the Moon only shows one face to the Earth, we've got volcanoes on Io, and ice geysers on Enceladus. ...

Read the full blog entry (http://www.astronomycast.com/solar-system/episode-47-tidal-forces/)

SingleDad
2007-Jul-31, 05:11 AM
hhhmm does this mean I should wait until the moon is over head before stepping on the scales =D Thanks guys.... off the read the blogs now =p

parallaxicality
2007-Jul-31, 02:49 PM
Could someone help me with this?

http://en.wikipedia.org/wiki/Galactic_tide

I'm trying to understand what causes the "bulge" on the opposite side of the Earth to the Moon. I get the bulge towards the Moon, but not the bulge away from it. I found a source that I thought explained it fairly simply, but someone else wrote in saying it was wrong. Help? Pleeeez?

SingleDad
2007-Aug-01, 04:42 AM
I'm trying to understand what causes the "bulge" on the opposite side of the Earth to the Moon. I get the bulge towards the Moon, but not the bulge away from it. I found a source that I thought explained it fairly simply, but someone else wrote in saying it was wrong. Help? Pleeeez?[/QUOTE]

OK, I'm gonna take a guess at this one, and maybe somebody can tell me how full of.... I mean how close I am :shifty: hehehe I love gravity.

I think it's caused by the spin of the Earth trying to "flatten the ball", and the Moon's gravitational pull. I'm not sure how to elaborate on that. Argh I hope you get the idea.

PS if I got it right ... thank you Astronomy Cast. I learned it all here.
if I got if wrong... It's all your fault Fraser for not having enough "GREAT!" days =p

hhEb09'1
2007-Aug-01, 05:52 AM
Could someone help me with this?There are two websites attached to this board (http://www.badastronomy.com/bad/misc/tides.html) :)

SingleDad
2007-Aug-04, 04:08 AM
OK so I got to think to much on tidal force and came up with a question. The moon orbits a point some where deep in the earth. The Moon is as so moving away from the Earth. So, doesn't that mean that at some point in time, the point at which the Earth and the Moon orbit will move outside the Earth's surface. When that happens won't the Earth and the Moon start to orbit each other? Since the Earth will be orbiting another object will it lose it's title of planet? Or, will we all be dead from one of Pamela's cosmic catastrophes by then? :lol:

hhEb09'1
2007-Aug-04, 06:40 AM
The Moon is as so moving away from the Earth. So, doesn't that mean that at some point in time, the point at which the Earth and the Moon orbit will move outside the Earth's surface. I believe we've discussed this before, and in order for that to happen, the moon would have to be so far out that the angular momentum of the earth/moon system would not be conserved, so it wouldn't happen. At one point, the moon will start to come back in, when the earth's rotation periond and the moon's revolution period match.

PeterHarrison84
2007-Sep-06, 01:37 PM
I thought this podcast was very interesting and it got me thinking about the moon's gravitational forces on man made objects in orbit. More specifically the ISS. When I tried to look this up the closest answer I found was that the ISS's orbit changes from about 320 km to 345 km, but it didn't say why this was. I can assume it probably has to do with a number of different things (eccentricity of the orbit or intentional altitude control) but I was wondering if anyone knew if the moon had any effect of this at all?