Celestia Forums

The phenomenon of limb darkening is real and observable... No arguement here. But is it observable to the naked eye as Celestia was originally supposed to resemble? It's visible to the filtered naked eye, certainly. The naked eye can't see sunspots on the unfiltered solar disc. Do we remove them to...

Yes. You don't need to spend too long looking at the sun (projected!) to notice that it has no fringe of atmosphere around the edge. The hard edge is more "realistic", tho it could use some limb darkening.

Thanks!

I see Pluto and Charon have specular maps in the distribution package. I can't really see much effect from them, but maybe that's something to do with my old computer. :( But my question is, how do we know the specular appearance of Pluto and Charon when we know so little surface detail? Was this ca...

Its true.

OK good.
Another difference in spelling to look out for is KHI / CHI.

Thanks!

Any thoughts on resolving the situation with regard to Greek letter names?

The sun has a new nearest neighbour in 1.5pre3 (may be earlier too I never looked). A tiny binary called KSI Sco A and B, at 4.16 ly. Problem seems to be in visualbins.stc Barycenter "KSI Sco" { RA 241.092450 Dec 92.529645 Distance 4.160160 } That declination is a bit nonstandard...

While the binary files are being revised, can the previously reported distance problem for 85 Peg also be fixed?

The distance is OK in stars.dat, 40.45lightyears. Its visualbins.stc that puts in the mistaken distance, so you could correct it by hand in the stc file, if nothing else.

StarSeeker wrote:(I noticed the Hun Kal crater at -21.4 longitude while it is by definition at -20, but no matter; I'm sure it's easier to nudge the terrain.)

Hun Kal is at -20 in the new update on CVS.
http://celestia.cvs.sourceforge.net/celestia/celestia/data/merc_locs.ssc

I just report what fixed the problem for me.

You need to update your numberedmoons.ssc file from the CVS tree.
I think the coordinate frame for Pluto changed in 1.5, so the old orbits don't work.

Did any of your add-ons require you to edit solarsys.ssc, changing the entry for either Saturn or one of it's moons?
What you describe sounds like a parsing error that makes Celestia stop before it gets any farther down the file.

shouldn't that make them a few metres across now?! Millimetres, since Radius is in kilometres. Some of the objects in the ssc would be reduced to tens of microns. I don't think that's the solution. The original data doesn't give radius, but planetary absolute mag (H). I would guess the ssc author m...

Some discussion of this on an old thread.

Yeah, on further thought this definition is very poorly defined and full of holes... I did'nt think restricting to the solar system was a problem. Would have been difficult to do anything else if "clearing the orbital neighbourhood" is a criterion for planethood. A proper definition of "clearing" i...

One of the requirements in the planet definition can't be confirmed for any extrasolar planets. That is, has the object cleared t's orbital neighbourhood? So narrowing on the Solar System is just putting the definition where the evidence is. Presumably referring to objects around other stars as "exo...

chaos syndrome wrote:As regards 2003 EL61, can hydrostatic equilibrium result in a prolate rather than oblate shape?

Google on "Jacobi ellipsoid".

No reason why they couldn't get a parallax near the ecliptic. The Earth still moves from one side of the sun to the other relative to the star. The star will just look as if its moving back and forward in a line instead of making a little circle in the sky. Draw a picture of the circle of Earth's or...