Rare Cassini image - two of Saturn's moons, Dion and Ra perform an optical illusion of merging
The Saturnian moons Dione and Rhea appear to merge in an optical illusion-like image taken by the Cassini spacecraft. Photo: NASA
An interesting image was recently sent by the Cassini spacecraft. Quite a few times several moons appeared in one frame, but not in this way. This is of course an optical illusion, but the two moons appear to cross and they also appear to be identical twins.
וIndeed, the two moons are quite close in size, but Dion, the smaller of the two, which is at the top of the image, is closer to the spacecraft, so the differences in size disappear. Due to the similar albedo or light reflectance between the two moons and due to the location of a relatively large crater near the south pole area of Dune, the moon appears to be transparently merging with Ra.
The diameter of Dion is 1,123 km and of Ra 1,528 km. The image was taken in visible light with Cassini's narrow-angle camera on July 27, 2010.
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What entertainment: I subtracted 1.1 from 1.6 and got 0.6 instead of 0.5.
Indeed, the number reported on him in the link given by Gadi is correct - also according to the data in the link I provided.
The distance between the moons at the time of the photo is almost half a million kilometers. Cassini spacecraft in the right place at the right time. More photos from the spacecraft in the following link:
http://gadieid.blogspot.com/2010/09/cassini-and-saturn-moons.html
Michael, thanks for the direction.
Some of my books are not with me at the moment but you definitely gave me points to follow.
The data here http://www.ciclops.org/view/6482/Conjoined_Moons?js=1
They are from the current event and according to them the distance between the moons at the moment of the photo is about six hundred thousand km
Oops….
The article from which I took the data is from an event that happened at a different time, so the calculation is based on incorrect data.
Itzik:
The moons are in motion and the distances between them change.
According to the data here:
http://www.universetoday.com/131/dione-passes-in-front-of-rhea/
And based on the fact that the moons appear to be the same size, it can be concluded that at the time of the photograph, the distance between them was about a million km
What is the distance between the two moons?
Hugin:
About the origin of the name Dion - see here:
http://en.wikipedia.org/wiki/Dione_(moon)
On how to determine names for the moons in general, see here:
http://en.wikipedia.org/wiki/Naming_of_moons
As far as I have dug into the matter, see or the ancient 'rea' is, as has been told since the days of the mythological dynasties, an innate product of the force of gravity: between Uranos (sky) and Gaia (earth).
In any case see it is the 'pulse'. That is, the breath [a life-giving soul].
But who is D'on?? Does anyone know by any chance..