Celestia Forums

Can anybody tell me which is the 'upper' side of venus according to celestia and relative to the BIG ring structure?

maxim

Not sure which ring structure you mean, sorry.
My usual landmark for checking the orientation of Venus maps is Maxwell Montes: highest area on the planet and very radar-bright, so it stands out clearly on topo and radar maps. It's also at very high latitude - if the map is orientated to IAU north, you see Maxwell Montes as a sharp-edged, vaguely tadpole-shaped, high/bright area very near the top edge. The three orange radar maps here are all orientated this way, and you can pick out Maxwell Montes as the only bright spot in the top quarter of the map, pretty much centred in the texture horizontally.

For Celestia, IAU maps of Venus need to be turned upside down by a 180 degree rotation, to place Maxwell Montes at the bottom edge.

Grant

Ok, thank you, that helped.
The ring structure I've meant is near the right border of the map, south of equator. It's the biggest of a series of rings weaved into each other.

granthutchison wrote:IAU maps of Venus need to be turned upside down by a 180 degree rotation

This is to be meant as an z-axis rotation I presume.

maxim

maxim wrote:This is to be meant as an z-axis rotation I presume.

Yes, if your x and y are the coordinate axes that lie in the picture plane, with z normal to the picture plane.

Grant