APOD: Flying Past Neptune's Moon Triton (2014 Aug 26)

Comments and questions about the APOD on the main view screen.
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Re: APOD: Flying Past Neptune's Moon Triton (2014 Aug 26)

Post by Nitpicker » Fri Aug 29, 2014 5:20 am

alter-ego wrote:
alter-ego wrote:First, although generally realistic in appearance, I'm convinced the video is not meant to be precise in stellar background content or dynamics during the flyby. In content I've been unable to make heads or tails out of the star background - I can't find any matching stars (searching large and small fields of view) even knowing the accurate coordinates of the receding moon.
I've identified the star fields, and they are the same constellation - the Big Dipper :o

During the approach, you see four bright stars roughly horizontal, they are, left to right: Alcor, Mizar, Alioth and Megrez. The FoV ~17.3°
Post-flyby, is tricky, but the 3 bright stars are: Phad (upper left), Megrez (middle) and Alioth (right). The FoV ~17.3°

So how can that be?
The post-flyby FoV is created by translating the approach FoV by ~3.5°, the inverting it! Interestingly, Triton's receding position is within 3.5°of its approach position, but inverting the receding-Triton FoV, makes it virtually unrecognizable.

It is true the star fields have identifiable members but it's clear that the background is only for effect and more enjoyable experience.

Pretty nifty!

FYI, the actual approach constellation is Sagittarius, and the post-flyby constellation is Camelopardalis.
Bravo, sir! :clap: