Starship Asterisk*

Charon: Moon of Pluto

Explanation: A darkened and mysterious north polar region known to some as Mordor Macula caps this premier high-resolution view. The portrait of Charon, Pluto's largest moon, was captured by New Horizons near the spacecraft's closest approach on July 14, 2015. The combined blue, red, and infrared data was processed to enhance colors and follow variations in Charon's surface properties with a resolution of about 2.9 kilometers (1.8 miles). A stunning image of Charon's Pluto-facing hemisphere, it also features a clear view of an apparently moon-girdling belt of fractures and canyons that seems to separate smooth southern plains from varied northern terrain. Charon is 1,214 kilometers (754 miles) across. That's about 1/10th the size of planet Earth but a whopping 1/2 the diameter of Pluto itself, and makes it the largest satellite relative to its parent body in the Solar System. Still, the moon appears as a small bump at about the 1 o'clock position on Pluto's disk in the grainy, negative,telescopic picture inset at upper left. That view was used by James Christy and Robert Harrington at the U.S. Naval Observatory in Flagstaff to discover Charon in June of 1978.

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Wow! That is an extraordinary achievement! Thanks for showing the pic.
Surely the significance and history of the that central belt and the different hemispheres has been discussed somewhere? A link would be gratefully received!
John

How many people would have noticed That that bulge by Pluto was
a moon?
Wonderful Charon! There was one photo (I couldn't copy) that
showed lines in the ice! My opinion; but i Thought that they looked
like roads!

orin stepanek wrote: ↑Sat Jun 03, 2023 1:21 pm charon_then_now_1024.jpg
How many people would have noticed That that bulge by Pluto was
a moon?
Wonderful Charon! There was one photo (I couldn't copy) that
showed lines in the ice! My opinion; but i Thought that they looked
like roads!

The Long and Winding Road in the Kintyre peninsula that inspired Paul McCartney

Uh, so where's Charon in the grainy image? Is this it? And if not, how the heck did they determine that another of those dots was anything more than just graininess?

Also, is this image is of the Pluto-facing side of Charon, does that mean that New Horizons passed between them?

johnnydeep wrote: ↑Sat Jun 03, 2023 7:48 pm Uh, so where's Charon in the grainy image? Is this it? And if not, how the heck did they determine that another of those dots was anything more than just graininess?

Chris Peterson wrote: ↑Sat Jun 03, 2023 8:20 pm

johnnydeep wrote: ↑Sat Jun 03, 2023 7:48 pm Uh, so where's Charon in the grainy image? Is this it? And if not, how the heck did they determine that another of those dots was anything more than just graininess?

charon_then_now_1024.jpg

Ah - thanks. And of course my Charon candidate was far too small compared to Pluto, which is only twice its diameter!

Of some interest is the large crater halfway between the centre of the image and about the 7 o'clock position, which appears to be overlaid by a (or two) features which form part of the 'belt'. This also happens further East at about the 2 o'clock position, indicating that the belt of deformation is relatively recent, although there are small craters on the overlying material too?