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Virtual space telescope inside Celestia?

Posted: 07.04.2017, 16:57
by john71
Is it possible to create a virtual space telescope inside Celestia?

I mean to have a picture of distant objects as a space telescope would see them.

What would a space telescope simulation be able to see (detect) "inside" Celestia (with changeable configuration and optical scale)?

How would far away exoplanets look? What would we see?

Posted: 07.04.2017, 18:26
by scalbers
Could one simply zoom in with a high magnification?

Posted: 07.04.2017, 19:43
by john71
Yes, that's the idea, but detection of light is a little bit different from zooming.

This a picture of Earth from a distance:

expoxibig.png


Added after 8 minutes 21 seconds:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3133830/

Added after 1 minute 6 seconds:
Another picture:

fig-1.jpg

Posted: 07.04.2017, 20:22
by selden
I'm not sure I understand what you're asking, but... you can place your viewpoint at the location of a telescope (whether it's the Hubble or one on the Earth's surface), select and track (t) the remote object that you're interested in, then increase Celestia's magnification (,) until you can see it.

Celestia really doesn't automatically modify illumination the way you seem to want, and it certainly doesn't have any focus adjustments.

Posted: 07.04.2017, 21:13
by scalbers
It looks like they are doing some interesting calculations of what the detailed spectrum looks like, and that is useful to help get more accurate color. This is along the lines of the DSCOVR comparisons and simulated imagery I've been referring to in some related threads.

Posted: 07.04.2017, 21:22
by john71
What I'm suggesting is this function:

1.) move to any spatial point in Celestia
2.) stop
3.) turn on the "virtual space telescope"
4.) select an object (star, planet, moon etc.)
5.) zoom on it
6.) adjust the picture as if it would be a real light source viewed from the space telescope (and not a digital "perfect zoom").

Added after 8 minutes 52 seconds:
Selden: as I understand direct visual observation of exoplanets will result in a few pixels of information (I mean in the coming decades). I would like to simulate this. It is not about focus adjustment, it is simply the lack of incoming light "data" from the object.

Posted: 07.04.2017, 21:38
by scalbers
It seems like a certain amount of zoom will produce an image of a planet that is say 10 pixels wide. This would indeed produce an "out of focus" appearance of the planet. Are you suggesting that if you even zoom in more than this to make it a bigger image it should only have the same amount of detail as a 10 pixel wide image?

In essence this would happen automatically if the texture only had that amount of known information in it. Perhaps you are thinking of a more detailed texture, then an option to select what a certain type of space telescope would see. We can talk about what these types of space telescopes are as well. Some use interferometry. Some simply look at rotation light curves and things like that.

Posted: 07.04.2017, 22:01
by FarGetaNik
So you want to simulate the view from some famous teleskopes, for example standing on Phoebe and simulate what details Hubble would see at Saturn? That would be a neat feature, particular for spacecraft. I love to recreate the Voyager flybys, but am lost with the zoom factor. I'd like to see what resolution Voyagers's cameras would see.

Posted: 07.04.2017, 22:53
by Fenerit

Posted: 08.04.2017, 04:47
by John Van Vliet
as posted on the other site
http://forum.celestialmatters.org/viewtopic.php?f=11&t=819#p13799

i get this from a zoom in on Europa
this was a eclipse of Europa caused by Io as seen from an Italian observatory at that time
1.png
2.png
3.png


or this - jupiter
hit "5" then "s"then "c" then zoom in with "<"
Screenshot_20170408_020938.png

Posted: 08.04.2017, 08:55
by john71
FarGetaNik, yes, you got it perfectly. :)

Added after 2 hours 19 minutes:
Fenerit: the pointing_hubblev07 add-on is almost exactly what I want, except the very last phase of zooming...

Depending on the space telescope's hardware the last picture should be somehow more realistic, not a simple digital zoom.

My main interest is direct exoplanet observation...what can be seen with a vastly more powerful virtual space telescope...

Added after 32 minutes:
By the way, why can't I zoom on exoplanets in Celestia from the Solar System?

Posted: 08.04.2017, 12:03
by selden
Celestia doesn't draw exoplanets from a viewpoint near our Sun because it only draws planets if the viewpoint is within 1 Light Year of that planet's sun.

Posted: 08.04.2017, 12:11
by john71
Selden, thanks, I see. That's a problem... :(

Posted: 08.04.2017, 14:14
by selden
If you write a script to implement such a "telescope" then it could automatically move the viewpoint close to the target star and then back again when the user somehow indicates that viewing has finished. (e.g. by clicking on the target star).

Posted: 08.04.2017, 14:26
by john71
OK, thanks, that should work! :)