Celestia in Education

[t00fri]

Guys, again a better definition of what is Celestia should be done on the official page and at sourceforge; because of the actual "Welcome to Celestia ... The free space simulation that lets you explore our universe in three dimensions." people can expect to see gravitational sim, but as this is not the case IMO it would be good to change this first sentence...

Sorry Christophe,

but I don't see the need for this, really. In Celestia the (idealized) observer camera is meant to be massless, hence does not feel gravity. So with this idealized Celestia camera, you can perfectly explore the universe in three dimensions. Even if some castrated gravity model was included, we still needed to have the camera move with a speed exceeding that of light. Otherwise, Celestia would become pretty boring while the observer is on it's LONG way to explore Alpha Centauri, say

Cheers,
Fridger

[hank]

Celestia is fundamentally a visualization tool. Among its essential features is the ability to observe time passing at an arbitrary speed and direction, and to jump instantly to distant times past or future. I don't know of any gravity simulation technique that can support Celestia's time manipulation features. However, trajectories can be pre-computed externally for visualization in Celestia via xyz files using any simulation method desired (including non-gravitational effects).

- Hank

[ajtribick]

Talking of all this gravitational stuff, I'm wondering if it would be possible to derive a decent CustomOrbit for the two gas giant planets of Gliese 876... their radial velocities seem to be well measured enough to be able to derive the inclination of the system, though the mutual inclinations haven't been found yet.

From what I can tell from the material I have read, the planets have already gone through a full precession cycle since discovery.

[Malenfant]

I think this is a VERY clear and amazing signal by the world's space science community that Celestia has won it's place right there!

This speaks for itself and naturally devaluates many of Malenfant's above arguments.

It really doesn't. I'm sure they'll find it very interesting and will go home and tinker with the program if they're not doing so already... but the fact remains that Celestia cannot be used to perform scientific analysis of data, and does not incorporate or account for gravity. The people Chris is talking to are probably interested in the program from the perspective of showing where their satellites are above Earth, but Celestia is useless for astrodynmaical research because it cannot accurate simulate on its own how the orbits of things evolve in time - you have to precalculate that and enter those orbits via STC or SSC files.

That's all I'm saying here. Celestia isn't a scientific analysis tool - it's a scientific visualisation tool. I'm not saying that scientists aren't important to listen to, but this forum has a lot more people who use the program for educational purposes than professional scientists. I really can't see anyone adding capabilities that will improve scientific analysis in Celestia (which is at most very basic) - but I can certainly see people adding capabilities that would enhance it as an educational and visualisation tool. Like your generalised galaxy database, or multiple wavelengths, or multiple star orbits and so on.

What started this all was your comment that you may just not bother reading this board because you weren't so much interested in the education side and didn't feel you should go out of your way to read posts about it. That irked me somewhat (quel surprise ) and I think it's an unwise position to take, given the number of people here who DO use the program for educational purposes - if developers just say "whatever, I can't be bothered to read comments by educators about how to improve Celestia from that perspective" then nothing will be improved to make it an even better educational tool.

The point was rather that Celestia is designed as a general accurate visualization framework rather than as a specialized tool for a particular purpose, like e.g. educational applications!

I don't honestly see the difference at all. Nobody's arguing that Celestia should become specifically an educational tool, to the point that you can't do anything else with it. Frankly I don't even see how it's possible to specialise it so much that all it's useful for is education. But I think educators will have suggestions for the development of the program that developers can respond to, and I don't think those suggestions would in any way degrade Celestia's capacity to do other things - and I certainly don't think they should be ignored either. This isn't an either/or situation.

I am however midly disturbed by the fact that while we're bickering over details and talking past here (as usual), an actual thread I've started about the educational uses of Celestia on this very board remains largely ignored, having had 69 views and only one response. Where is everyone?

[t00fri]

I am however midly disturbed by the fact that while we're bickering over details and talking past here (as usual), an actual thread I've started about the educational uses of Celestia on this very board remains largely ignored, having had 69 views and only one response. Where is everyone?

True, but fitting my prediction so far . Yet it's still early hours of the day. Our little "canonical" dispute (quel surprise ) either frightened all our teachers or turned them on. Let's see what is going to happen

[Vincent]

I know I, as well as many of the other educators in America, are just starting our school year. It is a very busy time for us and our answers are apt to be short, even one liners.

That's the same situation here in France. I am, like all other teachers and educators, very busy at the moment. I hope I'll have the time to talk about all my educationnal projects concerning Celestia quite soon here in this forum...

OK, just the time for a little lesson : in french, the name 'surprise' is feminine in gender. So the adjective 'Quel', which agree in gender with its name, also has to be feminine in gender , and so should be written : 'Quelle surprise !'

[Malenfant]

OK, just the time for a little lesson : in french, the name 'surprise' is feminine in gender. So the adjective 'Quel', which agree in gender with its name, also has to be feminine in gender , and so should be written : 'Quelle surprise !'

Doh! Duly noted

[t00fri]

OK, just the time for a little lesson : in french, the name 'surprise' is feminine in gender. So the adjective 'Quel', which agree in gender with its name, also has to be feminine in gender , and so should be written : 'Quelle surprise !'

Doh! Duly noted

Vincent,

of course I have just quoted Malenfant . I certainly know the gender of 'surprise'. After all, I once carried a French passport... (but helas..., it's a long time ago )

Bye Fridger

[Vincent]

Vincent,

of course I have just quoted Malenfant . I certainly know the gender of 'surprise'. After all, I once carried a French passport... (but helas..., it's a long time ago )

Bye Fridger

OK Fridger, that was just an opportunity for me to remind you that we, Frenchies, are such lesson givers....

[gandalf]

My apologies to Malenfant for not posting earlier. I have found from attendance at numerous faculty meetings that it is usually best if I keep my thoughts to myself! Right now I am taking a short break from cutting pipe for a planetarium that we are putting together that will (when finished) use Celestia as well as other helps (Stellarium, and also a simple punched cardboard star projector. Hey - we use what we have available)

I have found Celestia to be fantastic and useful in American high school physics. The lack of gravity is not a problem in that way.

But I was wondering ... about the gravity thing ... I understand that to have everything computed based on gravitational effects would be processor intensive to the extreme. Would it be perhaps possible to have a "throw object" command or even celx script that could take a single object, with given starting coordinates, velocity and user defined number of plotted points, that would write the xyz files once based on gravity, and therafter render everything - and the object - the way they normally would be without the gravity burden?

I am glad you have the "celestia in education" thread, it is worth it to have.

Many thanks for your time!

[Malenfant]

But I was wondering ... about the gravity thing ... I understand that to have everything computed based on gravitational effects would be processor intensive to the extreme. Would it be perhaps possible to have a "throw object" command or even celx script that could take a single object, with given starting coordinates, velocity and user defined number of plotted points, that would write the xyz files once based on gravity, and therafter render everything - and the object - the way they normally would be without the gravity burden?

One could probably write another program that calculated the xyz files (given the relevant input parameters - mass of object, gravity etc) that you could then visualise using Celestia. I dunno if a celx script could do those calculations when activated and then render the path of the object?

[Cham]

I can easily do this using Mathematica, like what I've done for my magnetic paths (Magnetic Earth addon, shown in another thread).

[selden]

The JPL Ephemeris server Horizons can calculate a trajectory within the solar system if you provide initial keplerian parameters. Its "vector" output needs only minimal modifications (to delete the textual date field) to be usable by Celestia.

I haven't actually done this, so I can't provide an example, however.

[greg57]

Partiview is another freeware 3D visualization tool which is often used by educators and scientists. Many of its features are complementary to what Celestia provides.


http://www.haydenplanetarium.org/hp/vo/du/index.html

Hi again Selden,
I have also become interested in Partiview, and it actually appears that Uniview, a real space visualization software based on it will soon be released for free, as is announced here. It seems damned close to Celestia in term of possibilities, and probably surpasses it given the appropriate hardware configuration. By the way, I was sad to discover that Celestia does not take advantage of the my dual-core CPU (CPU usage never gets over 99%), and then I could see on the activity monitor that it only used two threads, which probably explains why it can't take advantage of multiple processors.
All this to say that the close future seems quite worrying for Celestia.

Keep it up guys !

[tedub51]

i want to know what i have to do to seeing the educational files?

[fsgregs]

want to know what i have to do to seeing the educational files?

Sounds like you are having problems or are confused about the Activities. Please be much more specific, or email me with a private message and I'll be happy to work you through any problems. What have you done to load or download an Activity? What is happening when you try to run them, etc.?

fsgregs

[mrweber]

labdien lurkers

greetings from down under

i teach in a western australian senior high school and have just started to muck around in this astronomy area. i have created a small moodle site, sussed out the usual url's and put a small course together. scitec have a page that tells me whats in the sky this month

my first stop is sydney observatory to get the compulsory star maps. but you can't beat the open source stellarium for that. really kewell and at no cost.

next, the observation of the moon. virtual moon atlas for me. however i suspect google moon may be better.

finally, i use a program sent to me from stk.com that tells me when i can see satellites overhead. i watch iss last nigh. celestrak give the tle's required.

i am now at the point where my kids can spot venus, mars, mercury, jupiter and the southern cross. my next venture is to run some of the scripts in a solar system fly past.

next, celestia. i am not sure where to go. after the demo, i guess the solar system. however, i don't know how i will squeeze a 4 hour app into a 40 minute period

hope this was of some interest

c ya

mark

[fsgregs]

mrweber:

Given your 40 minute period, it is not practical for you to run an educational activity. They are designed to comprehensive teach Astronomy to a full class through personalized journeys by each student into Celestia space on their own computer. The Solar system tour represents Activities 3 and 4, or 3E and 4E. It takes several hours to complete the tour.

If you do not have the time, you can always launch Celestia 1.5.1 on your classroom computer, display it on an LCD projector, and using the keyboard controls of Celestia, take a trip to each of the planets and key moons. For example, talking in front of the class about Mercury or Venus or Mars is one thing ... but going there in Celestia, orbiting the planet, speeding up time to see it rotate below you, and even flying into the atmosphere or landing on the surface, is quite another. It can really bring your discussion of that planet to life, as you talk about it.

It is also quite possible to use the "click here" links inside an educational activity to go to some neat places. You just have to skip all of the written discussion in the Activity. Just open a written Activity in MS Word, launch Celestia through the image on page 3 or 4 of that Activity, then choose any celURL "click here" links you wish. Click once on them, and you will go to that time and place. Since the Activities come with lots of add-ons, using an Activity document as a guide works well for seeing a lot of great features. For example, Activity 8 is the Activity that covers the space program beyond Earth. It contains over 25 spacecraft add-ons that you can visit.

Hope this has helped.

Enjoy

Frank

[scaddenp]

i am now at the point where my kids can spot venus, mars, mercury, jupiter and the southern cross. my next venture is to run some of the scripts in a solar system fly past.

next, celestia. i am not sure where to go. after the demo, i guess the solar system. however, i don't know how i will squeeze a 4 hour app into a 40 minute period

Hello west islander. Greeting from across the ditch.
Point your kids at Celestia and give them a demo - they will likely teach themselves so much without you. Useful science stuff you can do though with Celestia on short time frames would be: Eclipses - dial up lunar and solar, look at the geometry of both. Moon phases - again, start on earth surface, go out to look at geometry. Look at constellations from different view points - that 3D perspective. Havent tried this, but you could look at celestial navigation. Telescope view of jupiters moons for occlusion. Lunar occlusion of stars. Compare at different longitudes. Teach them some respect for Captain Cook.

Use stellarium to look at seasonal change in constellation rising and setting - insights into primitive seasonal markers.

[fsgregs]

Hi everyone. Glad to see the forum up and running again.

I served as educational "coordinator" for Celestia for the last 10 years, and wrote all of the 12 flight plans/activities that have been distributed to the public via the motherlode education page, and my own educational website. I would say that tens of thousands of students in high schools and universities worldwide have taken one or more Celestia educational journeys in the past, and learned a great deal about the universe. In addition, hundreds of Astronomy and Earth Science teachers worldwide have loaded Celestia onto their desktops and displayed them on LCD projector screens in the classroom, visiting various visual locations. Both the kids and their teachers really like the program. It gets them out of the classroom and up into space. All of my students over the years have loved taking Celestia journeys.

One problem with using the program in education is that there are hundreds of addons available, sometimes duplicate addons with slightly different textures. For example, there are many textures available for the planets and moons. Those addons add up to well over 40 GB of data files if all loaded into the "extras" folder together. If a user wants to use a high res version of Celestia to visit a location in particular (e.g. - a black hole), he/she has to make sure that only the addons needed for that trip are loaded at program startup. Otherwise, the program can crash.

As a result, when I released the educational addons, I had to arrange the educational flight plans into categories and subjects. There is one journey that visits only the spacecraft around Earth orbit. Another visits the spacecraft that we've sent to other planets. A third journey covers the life and death of stars (from nebula to black holes). A 4th represents a general tour of the inner solar system, etc. Each journey contains a Windows link to a command file that calls a specific cfg file that opens a specific "educational-extras" folder containing only the addons needed for that one topic.

Another problem with educational use is the complex nature of Celestia's keystrokes. Kids placed in front of Celestia have no idea how to control the program, where to go, what buttons to press, etc. A teacher could yell out keystroke commands to them throughout the whole class period, but believe me, that does not work. The directions and url:cel links in how to control the program, where to go, how to orbit Mars or turn orbit lines on or off, or how to change time, or how to visit a particular nebula, MUST be written down for these kids, step by step. Even Lua Tools commands also need to be in writing. Occasionally, students get lost in what to do. From an educational standpoint, Celestia works beautifully if the audience has enough class time to use it properly and can read both the instructions and the educational description of what they are seeing. When teaching Astronomy with Celestia, I have to give my students several hours of computer lab time to take a particular educational journey (e.g. - 3 - 4 class hours to tour the inner solar system). There is also a need for some assessment feedback (a worksheet to complete). Otherwise, teens will simply try flying anywhere they want, and will learn very little about what they are visiting/viewing.

The fourth problem is flight plan length. If you as a teacher want to educate your students about the spacecraft humans have launched toward other planets, you will have a LOT of material. Hundreds of spacecraft have been launched. Which ones do you discuss? Does Celestia have a model of the craft to display? What do you say? How many spacecraft do you take students to visit in Celestia? How long and how many cel:url's do you embed in the flight plan document? To be thorough, a particular educational journey may be 25 pages in length and take at least 2 hours to complete. Some can reach 4 - 5 hours in length. This can be tiring for students. Even though Celestia is great to use, kids can get weary of using it for hours. You also need lots of computer lab time in your school. Computer labs are shared with all other departments, and reserving hours of time can be very difficult.

A final problem is computer type. I have not found any school laptop that will run Celestia 1.6.1, unless it is the default release with few addons. Most laptops and tablets do not have the graphics cards to run Celestia at higher resolution and reasonable frame rates. Only PC's have been up to the task. I've also had to load the program and all addons onto each PC in the computer lab. Loading it once from a central server and allowing each student computer to download it to their station, does not work well. The server hangs up.

Anyway, I am a strong believer in using Celestia for Astronomy education, and am slowly updating my existing Educational Activities to the present. I will be uploading them to motherlode one by one. I just updated the spacecraft journey to include Juno, New Horizons, Rosetta and Dawn. Look for them on the motherlode education page. I will monitor this thread for any posts or questions you all make.

Frank