Seriously cool Cassini pic

[The Singing Badger]

Titan + rings + Janus = whoah!

http://saturn.jpl.nasa.gov/multimedia/i ... 055798.jpg

[ElChristou]

Incredible shot...

[Malenfant]

Yeah, that's pretty amazing. I like how Titan's atmosphere appears to diffract (or do something optically wacky) when viewed through the rings...

[Chuft-Captain]

I wonder if they've got a colour enhanced version of this. That I'd like to see!

[selden]

To see this event in Celestia, you need an SSC file with the current orbital parameters for Janus.

Grant Hutchison was kind enough to generate one, which I've included below.

Code: Select all

#
#This little ssc to overwrite Janus with the elements for 2006 Mar 21 seems
#to do the trick. I get a reasonable reproduction of the photographic
#alignment at 21:47UT. Of course, the overexposed atmosphere of Titan doesn't
#appear in Celestia, so the view is much less dramatic.
#
#G

Replace "Janus" "Sol/Saturn"
{
        Texture         "janus.*"
        Mesh            "janus.cmod"
        Radius    96 # maximum semi-axis
        MeshCenter [ -1.552 1.358 2.257 ]

        EllipticalOrbit
        {
        Epoch           2453816  # 2006 Mar 21 12:00UT
        Period          0.70002746764788
        SemiMajorAxis   152042.445631502
        Eccentricity      0.00922014434064076
        Inclination       0.163500967745116
        AscendingNode   149.771653113819
        ArgOfPericenter 300.499917652034
        MeanAnomaly     319.537074829421
        }

        RotationEpoch           2453816  # 2006 Mar 21 12:00UT
        RotationOffset          230

        Albedo 0.6
}


and here's a Cel:// url to take you there
Janus and Titan from Cassini by Celestia

It's rather dim in Celestia, but increasing the Ambient Light level helps a little.

[Chuft-Captain]

Nice,

Thanks Selden/Grant.

When I zoom out from that CelURL, the Milky way is a strange shade of purple and has a sort of grid pattern.



And from elsewhere...


Anyone know what's going on here?

(using v1.4.1)

[selden]

Very strange.
I don't see those symptoms on this system.

512MB 2.4GHz P4 WinXP Pro sp2
128MB FX 5200, ForceWare v66.81
Celestia v1.4.1 final

[Chuft-Captain]

Must be my display.

.....time for a reboot perhaps!!!!

[Chuft-Captain]

BTW,

At same time I started getting this galaxy rendering problem (above), I stopped getting the new 1.4.1 flash screen at startup.

I wonder if it's not looking in the right place for these things?

[selden]

Celestia looks in its root directory for the splash screen. I don't see a flag in celestia.cfg that might control that, although there is a command-line directive to change the root directory to somewhere else.

You might consider renaming your current Celestia directory to something like \Celestia_old\
and installing a new copy of Celestia into \Celestia\ to see if that one does any better. If the new install works OK, it would imply that your current installation of Celestia has gotten damaged somehow. If the new, unmodified copy shows the same symptoms, then I'd be worried about problems elsewhere in your system -- either a virus or hardware starting to fail, perhaps.

[Malenfant]

I wonder if they've got a colour enhanced version of this. That I'd like to see!

Doesn't look like it - all the raw images of this are taken with the same filters (CL1 and CL2). So you can't make a colour image...

[Ynjevi]

There's no point to take color images of these events, because Cassini's camera is very slow and the events are really fast. Everything would move between the exposures making the color image construction painful.

[Malenfant]

There's no point to take color images of these events, because Cassini's camera is very slow and the events are really fast. Everything would move between the exposures making the color image construction painful.

Wouldn't be too much of a problem actually. You could (in Photoshop) just 'centre' the result on Titan or Janus by shifting the various images around and aligning them so the target was always in the middle. But then the other body would be moving across the screen.

I made a little animation out of all the raw frames showing the event anyway, looks rather cool .

Click here to see the animation!