Starship Asterisk*

Saturn in Infrared from Cassini

Explanation: Many details of Saturn appear clearly in infrared light. Bands of clouds show great structure, including long stretching storms. Also quite striking in infrared is the unusual hexagonal cloud pattern surrounding Saturn's North Pole. Each side of the dark hexagon spans roughly the width of our Earth. The hexagon's existence was not predicted, and its origin and likely stability remains a topic of research. Saturn's famous rings circle the planet and cast shadows below the equator. The featured image was taken by the robotic Cassini spacecraft in 2014 in several infrared colors. In 2017 September, the Cassini mission was brought to a dramatic conclusion when the spacecraft was directed to dive into ringed giant.

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I tried and failed to google the colour coding

I got to playing with the Cassini probe! Hoping I could transfer it to my post!
https://solarsystem.nasa.gov/missions/c ... pacecraft/ Doggie busy researching!

VictorBorun wrote: ↑Sun Jul 24, 2022 11:40 am I tried and failed to google the colour coding

There's a description in the infrared link in the APOD explanation. But even that is confusing because they show two examples of the dog in infrared. The first one we are mostly familiar with from Flir cameras. The hottest light is the bright yellow of the dog's eyes and tongue. The coldest is dark purple. However in the second one the hottest is red, while yellow seems to be cooler. The second one also has a bright blue color which is absent in the first. Apparently blue is a colder region than red or yellow, but it is still warmer than dark purple.

De58te wrote: ↑Sun Jul 24, 2022 1:26 pm

VictorBorun wrote: ↑Sun Jul 24, 2022 11:40 am I tried and failed to google the colour coding :(

There's a description in the infrared link in the APOD explanation. But even that is confusing because they show two examples of the dog in infrared. The first one we are mostly familiar with from Flir cameras. The hottest light is the bright yellow of the dog's eyes and tongue. The coldest is dark purple. However in the second one the hottest is red, while yellow seems to be cooler. The second one also has a bright blue color which is absent in the first. Apparently blue is a colder region than red or yellow, but it is still warmer than dark purple.

The furthest into the IR that the Cassini camera could see was 1 um. That's not thermal IR, just deep red, really. We're seeing reflected IR, not emitted IR.

If it were not for the fabulous rings, Saturn would be just another Uranus or Neptune. But those rings ARE fabulous!

Logical explanation for the hexagonal formation at Saturn's north pole--it's a giant snowflake.

Chris Peterson wrote: ↑Sun Jul 24, 2022 1:36 pm

De58te wrote: ↑Sun Jul 24, 2022 1:26 pm

VictorBorun wrote: ↑Sun Jul 24, 2022 11:40 am I tried and failed to google the colour coding

There's a description in the infrared link in the APOD explanation. But even that is confusing because they show two examples of the dog in infrared. The first one we are mostly familiar with from Flir cameras. The hottest light is the bright yellow of the dog's eyes and tongue. The coldest is dark purple. However in the second one the hottest is red, while yellow seems to be cooler. The second one also has a bright blue color which is absent in the first. Apparently blue is a colder region than red or yellow, but it is still warmer than dark purple.

The furthest into the IR that the Cassini camera could see was 1 um. That's not thermal IR, just deep red, really. We're seeing reflected IR, not emitted IR.

Thanks, I always though it could see into the thermal. Stunning image nonetheless.

Eric