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Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Wed Dec 24, 2008 1:15 pm
by neufer
http://apod.nasa.gov/apod/ap081224.html

The old misnomer of "sunrise" & "sunset" is fine for someone firmly affixed to a planet/moon; but what does it mean for an airline passenger ascending or descending vis-a-vis a twilight lit airport? By taking off to the west in the early evening from an airport does one snatch the last glimpse of a sunset or is one observing their own personal sunrise?

Here is the Apollo 8 in a figure 8 clockwise orbit around the moon observing the moon drop away while the earth appears to rise in the west. So should we call it an earthrise or something else :?:

The Apollo 8 Christmas Eve Broadcast 1968

Posted: Wed Dec 24, 2008 3:12 pm
by bystander
http://nssdc.gsfc.nasa.gov/planetary/lu ... _xmas.html
Apollo 8, the first manned mission to the Moon, entered lunar orbit on Christmas Eve, December 24, 1968. That evening, the astronauts; Commander Frank Borman, Command Module Pilot Jim Lovell, and Lunar Module Pilot William Anders did a live television broadcast from lunar orbit, in which they showed pictures of the Earth and Moon seen from Apollo 8. Lovell said, "The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth."
...
Borman then added, "And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas, and God bless all of you - all of you on the good Earth."

Re: Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Wed Dec 24, 2008 3:57 pm
by NoelC
I'm always impressed with images of the Earth and Moon how the darkish color of the moon is so apparent. They say it has the color and reflectivity of asphalt pavement, and that's hard to imagine when looking up in the night sky from Earth. Not so hard in this image.

Neufer, it seems Earthrise is a better way to get folks not present in the capsule to envision what is being seen. And besides, other than aliens living on the edge who might see the Earth rise and set due to libration, there's no fixed Earthrise/Earthset on the moon anyway.

-Noel

Re: The Apollo 8 Christmas Eve Broadcast 1968

Posted: Wed Dec 24, 2008 4:21 pm
by neufer
bystander wrote:http://nssdc.gsfc.nasa.gov/planetary/lu ... _xmas.html
Apollo 8, the first manned mission to the Moon, entered lunar orbit on Christmas Eve, December 24, 1968. That evening, the astronauts; Commander Frank Borman, Command Module Pilot Jim Lovell, and Lunar Module Pilot William Anders did a live television broadcast from lunar orbit, in which they showed pictures of the Earth and Moon seen from Apollo 8. Lovell said, "The vast loneliness is awe-inspiring and it makes you realize just what you have back there on Earth."
...
Borman then added, "And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas, and God bless all of you - all of you on the good Earth."
Shocked, shocked I tell you, bystander! :wink:

Re: The Apollo 8 Christmas Eve Broadcast 1968

Posted: Wed Dec 24, 2008 5:34 pm
by bystander
neufer wrote:Shocked, shocked I tell you, bystander! :wink:
:oops: Historical reference only.
Happy Holy Days to all! :wink:

Re: The Apollo 8 Christmas Eve Broadcast 1968

Posted: Wed Dec 24, 2008 5:44 pm
by apodman
bystander wrote:Happy Holy Days to all!
Can't find that "wreath" emoticon.

Re: Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Wed Dec 24, 2008 10:28 pm
by BMAONE23
I would think Earthrise is accurate and adequate considering that the term Moonrise is used as viewed from Earth.

Re: Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Wed Dec 24, 2008 10:52 pm
by neufer
BMAONE23 wrote:I would think Earthrise is accurate and adequate considering that the term Moonrise is used as viewed from Earth.
My fundamental question remains:

By taking off to the west on a jetplane from a airport in the early evening twilight:

1) does one snatch the last glimpse of a sunset or
2) does one observe their own personal sunrise?

Re: Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Thu Dec 25, 2008 1:15 am
by BMAONE23
If you were on a traditional jet (747) it would be a sunset though it would last slightly longer. You'd need to travel faster than 1100mph, beating the apparent speed of the Earths' rotation, to achieve a sunrise.

Re: Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Thu Dec 25, 2008 1:42 am
by Chris Peterson
neufer wrote:My fundamental question remains:

By taking off to the west on a jetplane from a airport in the early evening twilight:

1) does one snatch the last glimpse of a sunset or
2) does one observe their own personal sunrise?
Whichever you prefer. It isn't like there is only one accepted use for either "sunset" or "sunrise". It depends on context. I'd be perfectly happy with you saying that you see a personal sunrise at sunset.

Re: Figure 8 Apollo 8 ap081224 APOD (2008 December 24)

Posted: Thu Dec 25, 2008 3:28 am
by neufer
BMAONE23 wrote:If you were on a traditional jet (747) it would be a sunset though it would last slightly longer. You'd need to travel faster than 1100mph, beating the apparent speed of the Earths' rotation, to achieve a sunrise.
My idea was more about rapidly rising to a height
where the sun appears to rise; hence, "a last glimpse").

However, at 60ยบ North the earth rotates only half as fast as at the equator
and one can beat the sun to the other side of the earth at only
1/3 its equatorial speed by going directly over the pole.

Fiddling With Sunrise Sunset

Posted: Thu Dec 25, 2008 5:28 am
by apodman
Chris Peterson wrote:I'd be perfectly happy with you saying that you see a personal sunrise at sunset.
If you invert the ship just prior to the green flash, the sunset becomes a sunrise and the water becomes the air. That's how you get back from Davy Jones' locker.