Celestia Forums

In 1.6.0, when you're at Earth's surface, the entire blue sky can suddenly go black. I can duplicate the behavior most easily by tracking the Sun for a time.

Here is a cel//url that shows the black sky (Sun is not tracked in this):
cel://SyncOrbit/Sol:Earth/2010-03-11T20 ... rc=0&ver=3
If I Left-Drag the view up and down a bit, on my system blue sky blinks on and off.

From my searches of this forum and sourceforge, I see that "holes in the sky" were an issue at previous times. This is not just a "hole" in the sky, but literally the entire sky, because if you stop tracking the Sun, turn on Altazimuth Mode and scroll around the horizon, you see no blue sky at all. Also, the behavior does not appear on my system running 1.4.1. Curiously, changing the FOV will bring back blue sky, but the black sky can return if the Sun again moves slightly. Is this behavior related to that addressed in the Sourceforge topic "Black holes in sky rendering - ID: 1673696", whose status is still open? If so, is any progress being made in resolving this issue?

Thanks,
VikingTechJPL

Systems:
A) 1.6.0 on Dell Inspiron 1720 (laptop), Intel Core Duo 2.00 Ghz, 3.00 GB RAM, Windows Vista, NVIDIA GeForce 8600M G/GT
B) 1.4.1 on Dell dimension 4700 (desktop), Pentium 4 2.8 GHz, 512 MB RAM, Windows XP SP2, RADEON X300 128 MB

VikingTechJPL wrote:Here is a cel//url that shows the black sky (Sun is not tracked in this):
cel://SyncOrbit/Sol:Earth/2010-03-11T20 ... rc=0&ver=3
If I Left-Drag the view up and down a bit, on my system blue sky blinks on and off.

I confirm that this cel:// url gives a blue sky blackout when left dragging up and down. Celestia 1.6.0. Windows 7 64 Home Premium on a Dell XPS notebook (Nvidia 9400).
Guillermo

Greetings, Guillermo,

Thanks for verifying Earth's curious sky-color behavior in Windows 7.

Today I looked at it again on Earth, as well as on other planets and on Titan (since it has an atmosphere too), and found the same "blacking out". I can find it most easily by 1) going to the Sun, 2) centering the planet or moon, 3) going to planet or moon's surface and then 4) centering the Sun. But I also found that if I Left-Drag slowly downward after centering the Sun, first the sky returns to its native color, then lower down it blacks out again. However, "on" Jupiter I could not get the sky to go black. But, as you can see if you run the Jupiter links below, Jupiter has a different issue. Below its "horizon", everything is black. So it goes.

It also seems that on Venus you don't seem to have to Left-Drag the sky as much to get the sky to return to its native color. But that's just an impression.

If you'd like to look at the other circumstances I examined, here are their links:

Blackout Sky on Earth (Sun centered)
cel://SyncOrbit/Sol:Earth/2010-03-13T19:02:48.00004?x=zekGnoMK9v///////////w&y=chQwVuPi/f///////////w&z=U5HdIXz/Kg&ow=0.0711561&ox=-0.640761&oy=-0.758929&oz=-0.0915922&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3

Blackout Sky 2 on Earth (not looking at Sun)
cel://SyncOrbit/Sol:Earth/2010-03-13T19:02:48.00004?x=zekGnoMK9v///////////w&y=chQwVuPi/f///////////w&z=U5HdIXz/Kg&ow=0.380767&ox=-0.47922&oy=-0.596509&oz=-0.519174&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3


Blackout Sky on Mars (Sun centered)
cel://SyncOrbit/Sol:Mars/2010-03-13T19:02:48.00008?x=lqXuhJWhAg&y=1HRPIqr3CA&z=qNH/Q6Vo6v///////////w&ow=0.84506&ox=-0.197794&oy=-0.0492005&oz=0.494298&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3

Blackout Sky 2 on Mars (not looking at Sun)
cel://SyncOrbit/Sol:Mars/2010-03-13T19:02:48.00004?x=lKXuhJWhAg&y=1HRPIqr3CA&z=qtH/Q6Vo6v///////////w&ow=0.807895&ox=0.292612&oy=-0.328459&oz=0.392171&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3


Blackout Sky on Venus (Sun centered)
cel://SyncOrbit/Sol:Venus/2010-03-13T19:02:48.00004?x=9ZvcNzUM2P///////////w&y=AwhYI+kK/////////////w&z=90nD4UKuDA&ow=-0.458645&ox=0.489768&oy=0.640907&oz=0.37284&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3

Blackout Sky 2 on Venus (not looking at Sun)
cel://SyncOrbit/Sol:Venus/2010-03-13T19:02:48.00000?x=+pvcNzUM2P///////////w&y=BQhYI+kK/////////////w&z=8UnD4UKuDA&ow=-0.572677&ox=0.107997&oy=0.399648&oz=0.707573&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3


Blackout Sky on Titan (Sun centered)
cel://SyncOrbit/Sol:Saturn:Titan/2010-03-13T19:02:48.00000?x=tSxC36eG7////////////w&y=DvFTo+4MAQ&z=vABTbGTDBg&ow=-0.15014&ox=-0.78382&oy=0.274204&oz=-0.53656&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3

Blackout Sky 2 on Titan (not looking at Sun)
cel://SyncOrbit/Sol:Saturn:Titan/2010-03-13T19:02:48.00000?x=tSxC36eG7////////////w&y=DvFTo+4MAQ&z=vABTbGTDBg&ow=0.309324&ox=-0.740235&oy=0.521075&oz=-0.291293&select=Sol&fov=28.5035&ts=1e-008&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3


No Blackout Sky; instead Blackout "Below" "Surface" on Jupiter (Sun centered)
cel://SyncOrbit/Sol:Jupiter/2010-03-14T02:17:11.88418?x=ypS5scdXgwE&y=W8h4Zz2a&z=duHV6/ipNAE&ow=-0.158714&ox=0.692084&oy=0.689369&oz=0.143526&select=Sol&fov=56.4349&ts=-0.001&ltd=0&p=0&rf=40343&lm=32772&tsrc=0&ver=3

Regards,
Gary

VikingTechJPL wrote:I can find it most easily by 1) going to the Sun, 2) centering the planet or moon, 3) going to planet or moon's surface and then 4) centering the Sun.

Definitely right.

Launch Celestia 1.6.0 > h > g > 3 > crtl+g = no blue sky > left+drag = the blue sky appears when the Sun gets a little away from the center.

Instead: Launch Celestia 1.6.0 > h > c > 3 > crtl+g = blue sky, OK.

SVN 4992 (the latest I have here now) also has this problem.

It reminds me another display problem a short time ago (dissapearing Sun). Which Chris solved right away (thanks!)

Guillermo

It?s not a Windows 7 only related problem.It happens under Windows Vista and happened with XP.It seems to be a problem with a code...

Hello,

I have already reported this problem
Here        : Bug when displaying atmosphere

and here with more details : The hole in the ozone layer

This is a new bug in Celestia 1.6 that didn't happend in Celestial 1.5.1 and before.

Never mind, the "hole in the sky" problem is with us since much longer, including several patches...

See here e.g. from 2005, 5 years ago

viewtopic.php?f=3&t=7327&hilit=hole+sky&start=1

Fridger