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Earthrise

Posted: Sat Dec 24, 2005 1:12 pm
by orin stepanek
http://www.star.ucl.ac.uk/~apod/apod/ap051224.html
Ahh!! Earth; the most beautiful planet in the solar system. Home Sweet Home. Someplace on some star may be an equal; but we'll probably never see it.
Orin

Posted: Sat Dec 24, 2005 4:18 pm
by William Roeder
http://antwrp.gsfc.nasa.gov/apod/ap051224.html

We are spotting new extra-solar planets frequently now. In a few decades the 'scopes will be able to see an earth size planet with resolution like the picture.

Posted: Sat Dec 24, 2005 4:56 pm
by sgwmunro
Beautiful indeed. Based on the date of the picture the North pole must be in shadow which makes me wonder what are the two land masses that can be seen. Do you or anyone else know the global orientation in this shot?

stephen

Posted: Sat Dec 24, 2005 5:57 pm
by William Roeder
I actually see three land masses in the high res version.
left and right near the shadow and a small portion at the top of the image.

Rotating a global map I identify the right land mass as the western most point of africa. the left land mass is the western side of the south tip of africa. And the small portion at the top of the image is the eastern point of south america.

Picture of the Day---"Earthrise"

Posted: Sat Dec 24, 2005 8:50 pm
by Bill
"Earthrise" was taken from mankind's first venture out of Earth orbit---Apollo 8---37 years ago almost to the hour of this email. It was taken by a 70mm Hassalblad with 270mm lense on thin base kodak color film (no filters except oil smears on the spacecraft's window) from an altitude of approximately 60nm on the "back side" of the moon. Multiple shots were taken at various f stops but this is the one selected for wide distrbution (and a stamp). Earth's orientation is with its north pole pointing in the 3-4 o'clock/right direction of this view. After all yhese years it's too bad that NASA hasn't credited the actual photographer of this iconic photo.
PBS's "American Experience" resently showed the newly released film, "Race for the Moon", about the decisions and international situation that led up to the relatively "last minute" change of Apollo 8's original Earth orbit mission to test the Lunar module to that of a lunar orbit mission w/o a lunar module.

Posted: Sat Dec 24, 2005 11:50 pm
by MaNoX
Maybe a stupid question, but why aren't there any distant stars visible?

Posted: Sun Dec 25, 2005 12:52 am
by Bill
[quote="MaNoX"]Maybe a stupid question, but why aren't there any distant stars visible?[/quote][quote] Frozen urin and ice crystals floating around S/C refect enough light back into crew's eyes and camera at daylight f stop "dim out" stars. Quite another story when S/C is in double umbra (moon's shadow of both sunlight and earth shine).[/quote]

Posted: Sun Dec 25, 2005 10:16 am
by JohnD
Truly an iconic photo.
Probably has been for many, but it's now my screen background. The download from APOD comes up on the desktop without the moon and with the Earth in the right half of the screen - perfect unless you like lots of icons (sic!).
John

Posted: Mon Dec 26, 2005 2:17 am
by orin stepanek
http://www.star.ucl.ac.uk/~apod/apod/ap051224.html
This is what I originally thought I sent.
Orin

Posted: Thu Dec 29, 2005 4:45 am
by orin stepanek
If the same side of Luna always faces the Earth; wouldn't the Earth always be in about the same area of sky as viewed from the Moon??? Then there wouldn't really be an Earth rise.
Orin

Posted: Thu Dec 29, 2005 2:54 pm
by craterchains
It is the only solar system body that is full of life and not full of craters.

Beautiful. 8)

Norval

Posted: Thu Dec 29, 2005 2:55 pm
by BMAONE23
Interesting Point Orin

Posted: Thu Dec 29, 2005 3:17 pm
by craterchains
Yes, Orin did make a point with that. Looking out your moon base window, the earth would slowly go up and down just a bit because of moon wobble. But, it would also show you all the earth as the world turns. Now that would be a way cool view for a time. :D

Norval

Posted: Thu Dec 29, 2005 5:56 pm
by BMAONE23
Yea, It would only wax and wane over the 29 day period.

Posted: Thu Dec 29, 2005 11:58 pm
by SkyWatcher
orin stepanek wrote:If the same side of Luna always faces the Earth; wouldn't the Earth always be in about the same area of sky as viewed from the Moon??? Then there wouldn't really be an Earth rise.
Orin
Yes, but Apollo 8 was not on the Moon but moving around the Moon.
So the point of view was changing and they could actually see Earth rise and set.

who was that masked man (in the moon)?

Posted: Fri Dec 30, 2005 12:13 am
by planetquinn
Anybody notice that commentor “Bill” seems to know a lot of details about Apollo 8 and the earthrise photo? Solve that one, Einsteins

Posted: Fri Dec 30, 2005 1:04 am
by S. Bilderback
Bill:
I am honored to read the words of a true hero, I tip my hat to you.

Salute!

Posted: Fri Dec 30, 2005 2:30 am
by orin stepanek
SkyWatcher wrote;
Yes, but Apollo 8 was not on the Moon but moving around the Moon.
So the point of view was changing and they could actually see Earth rise and set.

Hi SkyWatcher! Good observation; and I realize that. I was referring to an Earthrise from the Moon; which would have the Earth pretty much in the same spot in the Heavens. The Earthrise was from Apollo 8. In my book it is still one of the greatest views in space. I would love to see a view of a full Earth from a site on Luna.
Orin

Posted: Fri Dec 30, 2005 3:02 am
by craterchains
Information from this page,
http://nssdc.gsfc.nasa.gov/planetary/lu ... 8info.html

William A. Anders, lunar module pilot.

Holy shit ! ! !

Sorry, just slipped out,,,,, :oops:

My hat, and a snappy salute to you. Now that took guts.

Wanna go out there again? :D

With all just due respect and my thanks.

Norval

an Earth-Moon puzzle

Posted: Fri Dec 30, 2005 11:10 pm
by planetquinn
I’ve enjoyed following the discussion about the view of Earth from the Moon, and this occurred to me: If you lived on the side of the Moon that never faced the Earth, how would you infer the existence of the Earth? It would take some sophisticated observation, I ’spect.
One of the most wonderful artifacts I’ve ever seen is a piece of bone that dates to about 30,000 years ago on which an early astronomer recorded the lunar phases. The Moon poses such an irresistable invitation to “figure it out” that I doubt that people would have made it to Celestial Mechanics 101 without it.

Posted: Sat Dec 31, 2005 12:56 pm
by Empeda2
Back after Christmas, and what is there to add?! Fabulous....

Posted: Sat Dec 31, 2005 6:03 pm
by orin stepanek
If you lived on the side of the Moon that faces away from Earth; you wouldn't know of the existence of Earth unless you had a mode of transportation. You would probably migrate around until you discovered the Earth. Wouldn't you like to live on the side that showed such a wonderful view of the Earth.
Orin

Posted: Sat Dec 31, 2005 7:19 pm
by planetquinn
I was thinking about observations from the back side of the moon that might lead to a theory of A Big Invisible Neighbor. I’m just quick-guessing here, but I imagine that planets would show a secondary retrograde cycle, and that there would be gravitational anomalies. Incidently, I don’t think there would be tides on the moon due to it’s orbital and revolution syncronicity. So, unless you were dead-center facing away from Earth, there might be an oblique gravitational pull at a constant (or very slightly wobbling) angle—unlike the revolving pull that makes tides on Earth.

Posted: Mon Jan 02, 2006 2:25 am
by orin stepanek
I'M not sure; but the gravitational tug between the Moon and the Earth might be what is causing the wobble of the moon as it orbits the Earth. So your invisible neighbor may be predictable.
Wouldn't it be neat if Luna rotated like the Earth. Then an Earth rise would be seen on the moon each day?---Just daydreaming!!!
Orin

Posted: Mon Jan 02, 2006 1:13 pm
by craterchains
That Big Invisible Neighbor is 1,500 miles big.

But, what you really want to know is where it is. :wink:

Norval