Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: neilep on 16/08/2007 22:31:10

Title: Does The Moon's Face Sway ? Even Just a little bit ?..and other questions !
Post by: neilep on 16/08/2007 22:31:10

Dear Moon Mavericks,

This is the Moon:

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fjeffreykishner.com%2Fimages%2Ffull_moon_large.jpg&hash=0c2566e2c461cb2c96f4b31ef77735c4)

Nice isn't it ?..Notice how full and familiarly sided it is ?



Now I know the Moon always faces the same side towards the Earth but is there not even the slightest movement ?..not even a millimeter a year or something ?..I do know that the moon is gradually getting further away..so...will it eventually leave orbit altogether ?

Is it some incredible coincidence that it spins the way it does ? or is it the norm considering the way it was formed ?

Also, isn't it a bit freaky that because "the Earth's distance from the Sun is about 400 times the Moon's distance from the Earth" and that "The Sun's diameter is about 400 times the diameter of the Moon." (Wiki quotes)...we get to enjoy wonderful solar eclipses ?

It does seem quite extraordinary when ewe think about it yes ?

Title: Does The Moon's Face Sway ? Even Just a little bit ?..and other questions !
Post by: allybalder on 17/08/2007 10:30:41

neilep
quote from here http://www.fourmilab.ch/earthview/moon_ap_per.html
see
A Different Point of View

You may have noticed while examining the pictures above that the two images of the Moon differ not only in size, but in the position of features on the disc of the Moon. This might seem puzzling in light of the frequently-stated assertion "the Moon always keeps the same face toward the Earth". But this generalisation is not strictly true; in fact, the combination of the eccentricity and inclination of the Moon's orbit causes the Moon, as seen from the Earth, to nod up and down and left and right. These apparent motions, the lunar librations, allow us to observe, over a period of time, more than 59% of the Moon's surface from the Earth, albeit with the terrain in the libration zones near the edge of the visible disc, only very obliquely.

Title: Does The Moon's Face Sway ? Even Just a little bit ?..and other questions !
Post by: neilep on 20/08/2007 18:28:48

Quote from: allybalder on 17/08/2007 10:30:41

neilep
quote from here http://www.fourmilab.ch/earthview/moon_ap_per.html
see
A Different Point of View

You may have noticed while examining the pictures above that the two images of the Moon differ not only in size, but in the position of features on the disc of the Moon. This might seem puzzling in light of the frequently-stated assertion "the Moon always keeps the same face toward the Earth". But this generalisation is not strictly true; in fact, the combination of the eccentricity and inclination of the Moon's orbit causes the Moon, as seen from the Earth, to nod up and down and left and right. These apparent motions, the lunar librations, allow us to observe, over a period of time, more than 59% of the Moon's surface from the Earth, albeit with the terrain in the libration zones near the edge of the visible disc, only very obliquely.

Oh My !!

I am so sorry for missing this reply.

THANK YOU allybalder for clearing this up for me. Fascinating !