Rotating planet moves across stars - Sun-sync planet coordinate

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FSword7
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Joined: 08.09.2017
With us: 3 years 8 months

Rotating planet moves across stars - Sun-sync planet coordinate

Post #1by FSword7 » 08.10.2017, 16:21

I have great idea for sun-sync planet coordinate system that faces sun at (0, 0). That is great view to see rotating planet with orbiting moons move across stars. That indicates that planet is orbiting around sun (star). That is good for education.

I did tried that on Celestia 1.6.0 with 100x time speed but it showed that earth is as center of universe instead. That's why I want to see planet moves across star background.

In the past, I had seen animation demo on the early NASA's Planet Quest website about exoplanets.

I was searching for formula through google but ended up sun-sync orbit formula (many sources) instead.

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FarGetaNik M
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Location: Germany

Post #2by FarGetaNik » 08.10.2017, 16:36

I am not quite sure what you want to do, but in Celestia you can just select the sun by pressing "H" then follow "f". Now you can speed up time to see planets pass by, or you can press "ctrl+g" to land on the sun and rotate with it.

Topic author
FSword7
Posts: 16
Joined: 08.09.2017
With us: 3 years 8 months

Post #3by FSword7 » 08.10.2017, 16:47

Added after 7 hours 5 minutes:
I am not quite sure what you want to do, but in Celestia you can just select the sun by pressing "H" then follow "f". Now you can speed up time to see planets pass by, or you can press "ctrl+g" to land on the sun and rotate with it.

I did trying that but that earth moves away. I mean fixed sun-sync planetocentric polar coordinates (like Lagrangian points) to see planet across stars.

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selden
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Post #4by selden » 09.10.2017, 09:36

Below is an example of an SSC definition of the Earth's L1 point.

Place your viewpoint there and watch (Track) the Earth. Over the period of a year, you'll see the Earth travel through the Zodiac.

Code: Select all

"Earth L1" "Sol"
{
    Radius 100
    Color [ 1 0 0 ]

    OrbitFrame {
         TwoVector {
            Center "Sol/Earth"
            Primary {
                Axis "x"
                RelativePosition {
                  Observer "Sol/Earth"
                  Target "Sol"
                }            }
            Secondary {
                Axis "y"
                RelativeVelocity {
                  Observer "Sol/Earth"
                  Target "Sol"
                }
            }
        }
    }
Selden

Topic author
FSword7
Posts: 16
Joined: 08.09.2017
With us: 3 years 8 months

Heliocentric Sync reference frame

Post #5by FSword7 » 29.04.2020, 22:43

Folks,

I now found solution. That script is not needed anymore but can add reference frame in frame.cpp would be called 'BodySyncFrame'. Here is very simple formula in computeOrientation.

q = lookAt<double>(center, target, {0, 1, 0});

Where

center = position of earth
target = position of sun

Now view spinning earth that moves across stars when increase time dilatation. Move to back of earth to see earth and sun moves across stars.

Tim


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