APOD: Interplanetary Earth (2019 Oct 12)

Comments and questions about the APOD on the main view screen.
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APOD: Interplanetary Earth (2019 Oct 12)

Post by APOD Robot » Sat Oct 12, 2019 4:09 am

Image Interplanetary Earth

Explanation: In an interplanetary first, on July 19, 2013 Earth was photographed on the same day from two other worlds of the Solar System, innermost planet Mercury and ringed gas giant Saturn. Pictured on the left, Earth is the pale blue dot just below the rings of Saturn, as captured by the robotic Cassini spacecraft then orbiting the outermost gas giant. On that same day people across planet Earth snapped many of their own of their own pictures of Saturn. On the right, the Earth-Moon system is seen against the dark background of space as captured by the robotic MESSENGER spacecraft, then in Mercury orbit. MESSENGER took its image as part of a search for small natural satellites of Mercury, moons that would be expected to be quite dim. In the MESSENGER image, the Earth (left) and Moon (right) are overexposed and shine brightly with reflected sunlight. Destined not to return to their home world, both Cassini and Messenger have since retired from their missions of Solar System exploration.

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shaileshs
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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by shaileshs » Sat Oct 12, 2019 4:48 am

In "view from Saturn", why does the sky is seen bluish (like we see on Earth) ? In the past, in famous "pale blue dot" photos, the sky was always seen dark black. Similar to how it's seen for "view from Mercury". Why blue in this photo ? Thanks in advance for all comments/answers..

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Ann
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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by Ann » Sat Oct 12, 2019 6:48 am

shaileshs wrote:
Sat Oct 12, 2019 4:48 am
In "view from Saturn", why does the sky is seen bluish (like we see on Earth) ? In the past, in famous "pale blue dot" photos, the sky was always seen dark black. Similar to how it's seen for "view from Mercury". Why blue in this photo ? Thanks in advance for all comments/answers..

The Earth is seen just above a bluish structure surrounding Saturn. Most of the rest of the background is (relatively) black.














Geysers of Enceladus. NASA/JPL/Space Science Institute.
Enceladus in the E-ring. NASA/JPL/Space Science Institute.


















The diffuse bluish structure could be the E-ring, which is produced by the geysers of Enceladus. The E-ring is bluish, because it reflects the sunlight in such a way that it looks blue.

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madtom1999
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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by madtom1999 » Sat Oct 12, 2019 10:07 am

I've never seen that big arrow?

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by Boomer12k » Sat Oct 12, 2019 11:20 am

Nice comparison... I find it amazing you can see the Moon from Mercury...


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Guest

Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by Guest » Sat Oct 12, 2019 11:41 am

We don’t need that giant arrow ruining the shot. I hate when they do that! Do they think we are idiots? What’s next, a skychart showing to find the moon? :evil:

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by De58te » Sat Oct 12, 2019 11:43 am

Boomer12k wrote:
Sat Oct 12, 2019 11:20 am
Nice comparison... I find it amazing you can see the Moon from Mercury...


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Even more amazing is that according to the information link of the Saturn image, the Moon is visible from Saturn as "a slight protrusion off the right side of Earth."

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by orin stepanek » Sat Oct 12, 2019 12:12 pm

earth_cassinimessenger_1024c.jpg
Must be my eyes; I could not make out Luna from the Saturn view! :mrgreen: Gonna have to check my implants; as my eye Dr. says I have 20/20! :roll: :eyebrows:

Added the blowup!
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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by gahs » Sat Oct 12, 2019 1:27 pm

If you want to see the picture without the arrow, see the Cassini Imaging site at http://ciclops.org/view/7696/The-Day-th ... ak-Preview
The description at that site confirms the broad, diffuse E ring is seen in this image, which is part of the wider field you can see here http://www.ciclops.org/view/7699/The-Da ... miled?js=1 Image --- lots of info there!
There is also a higher resolution narrow-field view of the Earth and Moon taken by Cassini at the same time here: http://ciclops.org/view/7695/One-Specia ... anet-Earth Image

(I love the Cassini Imaging Laboratory Operation Center site!)

jisles

Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by jisles » Sat Oct 12, 2019 1:43 pm

Enlarging the Cassini photo, I see a point of light to the lower right of the Earth. Could that be the Moon?

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by neufer » Sat Oct 12, 2019 1:51 pm

https://solarsystem.nasa.gov/resources/2242/earth-moon-and-asteroid-bennu/ wrote:
<<OSIRIS-REx used its NavCam 1 camera to capture this image of three familiar planetary bodies: asteroid Bennu, Earth, and the moon.

Despite the spacecraft’s distance from home – about 71 million miles (114 million kilometers) – Earth and the Moon are visible in the lower left due to the long exposure time used for this image (five seconds).

The spacecraft’s range to Bennu is only about 27 miles (43 kilometers), so the asteroid appears highly overexposed in the upper right. The head of the constellation Hydra is also visible in the lower right portion of the image.

NavCam 1 is a black-and-white imager that is one of three cameras comprising TAGCAMS (the Touch-and-Go Camera System), which is part of OSIRIS-REx’s guidance, navigation, and control system. TAGCAMS was designed, built and tested by Malin Space Science Systems; Lockheed Martin Space integrated TAGCAMS to the OSIRIS-REx spacecraft and operates TAGCAMS.>>
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Ann
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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by Ann » Sat Oct 12, 2019 2:34 pm

gahs wrote:
Sat Oct 12, 2019 1:27 pm
If you want to see the picture without the arrow, see the Cassini Imaging site at http://ciclops.org/view/7696/The-Day-th ... ak-Preview
The description at that site confirms the broad, diffuse E ring is seen in this image, which is part of the wider field you can see here http://www.ciclops.org/view/7699/The-Da ... miled?js=1 Image --- lots of info there!
There is also a higher resolution narrow-field view of the Earth and Moon taken by Cassini at the same time here: http://ciclops.org/view/7695/One-Specia ... anet-Earth Image

(I love the Cassini Imaging Laboratory Operation Center site!)

The enlarged version of the Earth-Moon picture above confirms that the Earth looks slightly bluish from Saturn, while the Moon does not.

Ann
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neufer
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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by neufer » Sat Oct 12, 2019 2:51 pm


Ann wrote:
Sat Oct 12, 2019 2:34 pm

The enlarged version of the Earth-Moon picture above confirms that the Earth looks slightly bluish from Saturn, while the Moon does not.
Art Neuendorffer

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by Respect SI » Sat Oct 12, 2019 7:46 pm

Is it possible in the future to use non-retard unit for the distance ?

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by zendae1 » Sat Oct 12, 2019 8:02 pm

It's little pics like that which brings tears to my eyes. Thank you Master Sagan for providing the first.

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Re: APOD: Interplanetary Earth (2019 Oct 12)

Post by TheOtherBruce » Mon Oct 14, 2019 7:25 pm

madtom1999 wrote:
Sat Oct 12, 2019 10:07 am
I've never seen that big arrow?
Look at where it is — down below the Earth. It's only visible in the southern hemisphere. Image
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