APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Comments and questions about the APOD on the main view screen.
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APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by APOD Robot » Wed Sep 01, 2010 4:03 am

Image Earth and Moon from MESSENGER

Explanation: What does Earth look like from the planet Mercury? The robotic spacecraft MESSENGER found out as it looked toward the Earth during its closest approach to the Sun about three months ago. The Earth and Moon are visible as the double spot on the lower left of the above image. Now MESSENGER was not at Mercury when it took the above image, but at a location from which the view would be similar. From Mercury, both the Earth and its comparatively large moon will always appear as small circles of reflected sunlight and will never show a crescent phase. MESSENGER has zipped right by Mercury three times since being launched in 2004, and is scheduled to enter orbit around the innermost planet in March of 2011.

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by mexhunter » Wed Sep 01, 2010 4:09 am

And there are all of us.
Grettings
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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by john Green » Wed Sep 01, 2010 4:11 am

What is the point of light to the far right of the Earth and moon system. Is it Mars?

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Ann » Wed Sep 01, 2010 4:33 am

Earth and Moon, the double planet.

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by bystander » Wed Sep 01, 2010 4:43 am


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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by BMAONE23 » Wed Sep 01, 2010 4:46 am

john Green wrote:What is the point of light to the far right of the Earth and moon system. Is it Mars?
According to the info in an older apod 060319 the current position of Mars is behind Earth as seen from Mercury's orbit. Mars would be a likely candidate for the dot to the right of the image and in line with The Earth/Moon system

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Questioner » Wed Sep 01, 2010 5:39 am

Just on this pic, I am curious as to what the 3 streaks of light are on the top right of the large image...

One is quite large and the other 2 smaller.

http://apod.nasa.gov/apod/image/1009/ea ... er_big.png

Any info would be great.

pking51

Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by pking51 » Wed Sep 01, 2010 6:22 am

Hi Robert,

Would the earth / moon pair be visible to the naked eye from this position? Or would one need binoculars or telescope?

Paul

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Czerno-1 » Wed Sep 01, 2010 7:21 am

pking51 wrote: Would the earth / moon pair be visible to the naked eye from this position? Or would one need binoculars or telescope?
A rapid & grossly inaccurate mental calulation yields a Earth-Moon separation of the order of 10 arc minutes as seen from the Sun (or Mercury). So, yes I assume they could be separated by eye.

gambit

Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by gambit » Wed Sep 01, 2010 10:43 am

john Green wrote:What is the point of light to the far right of the Earth and moon system. Is it Mars?
If this was taken 3 months ago there wouldn't have been anything behind us as seen from Mercurys orbit. Saturn and Mars were at a 90 degree angle to the right, and Jupiter would be about the same to the left.

rochelimit@hotmail.com

Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by rochelimit@hotmail.com » Wed Sep 01, 2010 11:39 am

Ann wrote:Earth and Moon, the double planet.

Ann
exactly what I thought!

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by orin stepanek » Wed Sep 01, 2010 12:03 pm


Earth and Moon, the double planet.

Ann
And then there's the other double planet
http://www.google.com/images?rlz=1T4GZA ... 66&bih=302
The movie of Messenger zeroing in on Mercury http://www.youtube.com/watch?v=otF2FjpCyZk neat! 8-)
Orin

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Redbone » Wed Sep 01, 2010 12:14 pm

I would've thought that the blue planet would appear a bit blue? It is always amazing how large our moon is compared to the Earth.

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by owlice » Wed Sep 01, 2010 12:15 pm

I love this image.

Earth appears a little flattened on the left (non-Moon) side, as though it were a small ball of clay that had been made, put down on a table, and then picked up and positioned for this family portrait, table-side to the left.

I love this image. I was very glad to see it as today's APOD!
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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by garyj » Wed Sep 01, 2010 12:45 pm

Because not everyone who views EPOD is an astronomer, the commentary should have included something about why the white moon blob appears to be so close to the white earth blob. After all, the moon is about 30 earth diameters away from earth. Perhaps "resolving power" of the camera?

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by orin stepanek » Wed Sep 01, 2010 12:51 pm

garyj wrote:Because not everyone who views EPOD is an astronomer, the commentary should have included something about why the white moon blob appears to be so close to the white earth blob. After all, the moon is about 30 earth diameters away from earth. Perhaps "resolving power" of the camera?
As the Moon rotates around the Earth it is either behind the Earth or in front of it; so when the picture was taken; the moon wasn't along side the Earth toward the camera!
Orin

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by planetquinn » Wed Sep 01, 2010 12:56 pm

Earth in Cancer. I think the bright star to the right is Aldebaran.

jac12358

Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by jac12358 » Wed Sep 01, 2010 1:30 pm

Earth in Cancer - really? I was wondering what star field I was seeing. Could not make it out. Humbling, really. I guess you'd have to know the date and position of Messenger to work out the reverse view. How many arcs wide is the whole image?

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by emc » Wed Sep 01, 2010 2:01 pm

Such a cool picture... Today’s APOD got me wondering if either Voyager is equipped to research a means to identify Earth like planets by reporting what is seen when looking back at our pale blue dot. Apparently not, the spacecraft are slated to lose power and fuel around 2020.

http://voyager.jpl.nasa.gov/mission/interstellar.html
The Voyagers have enough electrical power and thruster fuel to operate at least until 2020. By that time, Voyager 1 will be 12.4 billion miles (19.9 billion KM) from the Sun and Voyager 2 will be 10.5 billion miles (16.9 billion KM) away. Eventually, the Voyagers will pass other stars. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Camelopardalis. In some 296,000 years, Voyager 2 will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky . The Voyagers are destined—perhaps eternally—to wander the Milky Way.
And after looking at today’s impressive picture and reading Voyager’s fates… I can't help but feel a sense of physical isolation from the distant stars and yet a mental joy at what science is revealing for us. Kind of like watching one of those fabulous cooking shows on HDTV and no food in my kitchen...

At least I have my wheelbarrow… (Thanks Orin!)
Ed
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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Randy Stubbings » Wed Sep 01, 2010 2:31 pm

Why does the Earth-Moon distance appear to be less than one Earth diameter?

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by orin stepanek » Wed Sep 01, 2010 2:35 pm

emc wrote:Such a cool picture... Today’s APOD got me wondering if either Voyager is equipped to research a means to identify Earth like planets by reporting what is seen when looking back at our pale blue dot. Apparently not, the spacecraft are slated to lose power and fuel around 2020.

http://voyager.jpl.nasa.gov/mission/interstellar.html
The Voyagers have enough electrical power and thruster fuel to operate at least until 2020. By that time, Voyager 1 will be 12.4 billion miles (19.9 billion KM) from the Sun and Voyager 2 will be 10.5 billion miles (16.9 billion KM) away. Eventually, the Voyagers will pass other stars. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Camelopardalis. In some 296,000 years, Voyager 2 will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky . The Voyagers are destined—perhaps eternally—to wander the Milky Way.
And after looking at today’s impressive picture and reading Voyager’s fates… I can't help but feel a sense of physical isolation from the distant stars and yet a mental joy at what science is revealing for us. Kind of like watching one of those fabulous cooking shows on HDTV and no food in my kitchen...

At least I have my wheelbarrow… (Thanks Orin!)
Ed; you remember that? :D
here's your solar system portrait! 8-)
Image
Orin

Smile today; tomorrow's another day!

hess

Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by hess » Wed Sep 01, 2010 2:50 pm

It just hangs there-no strings!! Awesome!!!!!!!!!!!!

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Ann » Wed Sep 01, 2010 3:08 pm

Randy Stubbings wrote:Why does the Earth-Moon distance appear to be less than one Earth diameter?
Probably because the Moon is either slightly behind or slightly in front of the Earth in its orbit around it. Theoretically the Moon could have occulted the Earth, so that it wouldn't have shown up in this image.

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Randy Stubbings

Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by Randy Stubbings » Wed Sep 01, 2010 3:22 pm

Right after I posted my comment I went, duh!

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Re: APOD: Earth and Moon from MESSENGER (2010 Sep 01)

Post by biddie67 » Wed Sep 01, 2010 3:31 pm

Thank you Messenger!!! What a mind-opening view of our fine planet and its companion!