Celestia Forums

chris wrote:
There are a couple things that I want to do in Celestia to make it easier to create custom trajectories. Reloading objects while Celestia is running is one of them.

--Chris

Thank you, Chris. I look forward to the day this capability is in.

Is there any way trajectory data can be piped into Celestia, perhaps as standard input or via sockets? As the user of a lot of older trajectory optimization programs, having the ability to display a trajectory real-time in Celestia would be a big plus. This would let the user use whatever trajectory...

Its just some trajectory work I've done. I plan on having it published as a NASA technical report, after which it should be accessible from a NASA website. Once that happens, I'll post the link here for you.

Since I use Celestia for mission visualization, this would come in very handy. Its aggrivating to have to restart Celestia every time I update an xyz file and want to draw the updated trajectory.

To put in L4 or L5 as an orbit isnt really valid.

Objects orbit the Lagrange points, they dont sit directly on them.

Sorry, for being still not with you: You say above "Instead, they're subdivided into straight line segments.". Splines are curve segments the shape of which depends on 3-4 points, an initial one, a final one and 1-2 "control" points that determine the curvatures of that curve segment. So how can a ...

Or better yet...allow object classes to be added dyamically

Trojans
Mars Missions
Inner Oort cloud objects
etc.

Perhaps it would be best to allow these to be controlled with settings in celestia.cfg . . .

Yes please, if it is possible to do so. I rely on superprecise orbits, speed is far less of an issue.

Following alphap1us's instructions, everything seems to compile fine, but I get an error on linking. Type Message Location Error Undefined symbols: macosx:0 Warning warning suggest use of -bind_at_load... macosx:0 An executable is generated, but its only 372kb on the disk, whereas the release versio...

As for the latter...look for the file start.cel in your Celestia folder (or CelestiaResources on OS X). It contains a script that tells Celestia to look at Io on startup. I dont know if you can control display modes from the cel script. If you do a google search for "celestia cel scripting" you will...

There's still a slight discrepancy between the positions Horizons returns and the positions I compute from the JPL ephemerides--for Jupiter, it's up to 200km. At this point, I suspect the problem may be related to a slightly different time standard. Chris, There are a few things you may want to loo...

What is the extent of the JPL ephemeris file support? Is this DE403/5/6 support, or SPICE kernel (spk) support?

Can these be used as the ephemerides for planets and moons, or are they intended only for spacecraft?

The budget for ISS drops to 0 in 2017, which is probably close to what it would have been anyway. The budget sand-bar chart is available in PDF here

Heres another way to look at it. Celestia is a tool. When you see graphics posted on websites, do you expect to see credits for Photoshop, or Excel when charts are posted?

I disagree. While it is important that Celestia get proper credit, it would be a detriment to most users to obscure a portion of the screen with the text.

And more importantly, Celestia is open source. If the offending party wanted to remove that tag, they could simply recompile.

Outstanding. I hope this is included in the main release as soon as possible.

Celestia doesn't do the physics for propagation of the planets, it interpolates an ephemeris. Most ephemerides do include lightspeed gravitational effects.

Ahhh now we've opened a colossal can of worms :) I'm somewhat cautious of splitting the spacecraft definitions into several files. XML would probably be the best solution in the long run. As for backward compatibility, a simple perl script could be written to convert from the "old" ssc/xyz format in...

Youre right. But I still think the potential should still be there for higher fidelity, larger models. Smaller files without all that data should still be accessible. I believe someone mentioned accessing zip files in another thread. Perhaps all the necessary files for an addon (ssc, xyz, etc) could...

Hello Paolo, I would like to see an enhanced xyz file as well, although I still favor separating the xyz file from the ssc file. Primarily because I think it is easier to generate the xyz data in a separate file, incorporating it into the more object-oriented ssc file could be messy. You suggested s...