The End of Earth - add-on is coming soon

[granthutchison]

Is there a way to create a fictional star in space with a texture and flare, and give it a neutron star texture? If so, please tell me how.

Frank, I guess you'll have noticed I posted this information immediately prior to your last post.

I don’t know if there is a way to find out where the habitable zone around the sun at this time might be but if its near Jupiter than you can melt Europa into a water covered ball and make a whole lot of lakes and seas on Ganymede and Calisto.

Don, the habitable zone for an Earth-like world around a 2500K red giant with a radius of 1AU is way out at 40AU. Jupiter fries.

Grant

PS: Added later, after reading Apollo7's post on another thread. 40AUs is the minimum distance for a habitable zone, since 2500K is implausibly cool for our giant star. For a 3500K M2III star, the habitable zone pushes out to almost double that distance.

[Cormoran]

Yummie,

Earth Flambee as a starter, followed by Medium-Rare Mars, Jupiter fries and a Saturn Milkshake (but no rings).

Not sure about Uranus as dessert

40 Au? Wow.... Neptune (the fish course hehe) and Pluto (a Korean dish?) as comets with comae a billion miles long.

Sorry, moment of madness due to massive vista overload hehehehe

Cormie

[fsgregs]

Everyone, thank you for the help. This will turn out to be a GREAT activity. It should be done in couple of days, and I'll post it then. Since it will cover a lots of things that are not in Celestia's default downloads, there will be lots of add-ons to get. I'll try to zip them all and add them to my website, but ....

Grant, thanks for the neutron star. I've created it and it looks neat, however, I had to change the star from HIP 450000 to HIP 600000 because Ras has already used 450000 in his Rosette Nebula system add-on. Here is a screenshot of the final version:



If I understand the posts, the only planet within the habitable zone after the sun red giants, will be Pluto (at about 40 au). If true, I will not need a texture for Europa. Ras, I will use two of your gas giants for the transformed Jupiter and Saturn. Thanks. If humanity survives 5 billion years, I assume Pluto will have been terrraformed long in advance of our need to move to it, so I am putting lots of colony lights on it. I also will put some space stations around it. The only good ones I have are the rotating station from 2001, which I am using in other activities, and the station from Star Trek, Deep Space 9. Does anone else have some big, well textured space stations of the future I can plug in here?

Ras, you will of course recognize Muphrid B as my Red Giant. It is an awesome texture. I am also using your new protostar texture as a highlight of the first part of the activity. What perfect timing. I did change the ssc a bit so that the planets you have imbedded in it revolve around the Protostar at the same speed as the rest of the Nebula. Hope that is OK.

Don, with respect to Mars, I don't want to modify the existing Mars texture because vitually every surface feature on Mars will be totally different in 5 billion years. All the volcanoes will be long gone (eroded), Valles Marinaras will be filled in with blown sand and no longer visible, and the ice caps will have long melted. Assuming we do terraform Mars, there may even be ocean basins that will boil when the Red Giant gets too close. So I need a new texture for the Mars of the future, one with good detail and a good bump. I will check through my list of add-on textures, but if anyone can think of a texture that would fit the bill, please let me know. Don, if you were able to salvage Orpheus from your hard drive crash, perhaps it would make a fine Mars of the future. What do you think?

[Brendan]

Won't the red giant sun be hot enough to make the Kuiper belt and Oort cloud objects have coma and tails all the time? That might be a neat sight seeing all of those orbiting the sun.

Brendan

[ElPelado]

If humanity survives 5 billion years...

1) I dont really think that it is possible, but...
2) If that happens, don't you think that Pluto is toooooo small for us? Dont you think that maybe we moved to an other star?
Do you imagin seeing our Sun turn to a Red Gigant from an other star???...

[Don. Edwards]

Frank,
Orpheus' surface is too volcanically active and has some surface water in basins for it to be of any use unfortunately in this exercise. I do have it filed away with its multiple sister textures witch one of then might fit the bill. I will have a look through the various textures and see if one might come close.
I am not sure if anyone out there is familiar with working with Bryce, but it has the ability to import terrain data like bumpmaps from USGS and then use its erosion feature you can change the surface. So as an example we could get a terrain map of Olympus Mons and import it into Bryce we could erode it down to look like something never seen before. Same with Mariners Valley. It would be a big project but if someone knows how to do it, it could be worth it for some other project if not this one.
I will get back to you on those textures.

Don. Edwards

[Rassilon]

The ssc modification I refer to in my readme's only applies to the same addon resubmitted on another site...

[Guest]

Any new informations about this project? It sound very interesting.....

[fsgregs]

OK, good news. The Life and Death of Stars Educational Activity is done and has turned out to be stunning. It is a visually great journey through many of Celestia's best add-ons, with over 20 stops. It runs 26 pages to read on a step by step journey, and takes 1 1/2 to 2 hours to complete. When you are done, you will know a great deal about how stars are born, live and die.

That's the good news. The bad news is that there are 22 separate add-ons used in the activity. These include 5 nebula, 2 protostars, 7 star textures, 7 high res planet textures, a spacecraft, and such exotic beasts as rotating pulsars, black holes (2 different ones) and black dwarfs. Many of you have some of these add-ons, but some of them are modified versions of existing add-ons and some of them are new (I created them). I have to assume that you have none of them, so I've got to provide them.

I have done so in a set of five zipped files, totaling , 57 MB. I have no choice. That makes for some hefty downloads.

You cannot just download these add-ons into your extras file, without first checking to see if you already have them. You may have them under different names. If you put both sets into the extras file as the same time, Celestia will draw two objects at the same time in the same spot, and possibly lock up.

There is also the problem of the ssc file. The Activity changes the future by creating/drawing new textures for Earth, Mars, Jupiter, Pluto and Charon when our Sun goes Red Giant. I have tried to go beyond the year 9999 in Celestia to set the stage for such an event. I can do so by setting the clock to run faster, but I cannot enter a date higher than 9999, so I have created the new textures to take effect in the year 9998. That means the solarsys.ssc file that you are using in Celestia must be edited with an "Ending" command. to command the program not to draw those 5 planets/moons after 9998. It is a simple set of edits that won't harm the program, but it must be done. For folks unfamiliar with ssc files or edits, it will be a bit confusing.

I've put together a detailed read-me file for the activity, which hopefully, will explain it all.

With Don Goyette's excellent editing help, I/we are proofing the Activity now. I hope to make it available on my website in final form within a few days. When I do, I'll announce it as a separate thread, and update this thread.

Till then ....



Frank

[selden]

Frank,

Usually the size of a download is determined by the sizes of the surface texture images. What sizes are you using? Would a lores version of the activity be significantly smaller if you used 512x256 textures?

[granthutchison]

Black dwarfs?
I take it this involves a far-future date, since the Universe isn't old enough yet to have produced such a beast ...

Grant

[fsgregs]

Dear Selden:

Basically, the size of the add-ons is due to the number of them. We make 28 stops to lots of nebula, stars, planets, and exotic beasties, using 23 add-ons. When they are added up, they take a lot of RAM.

The only high-res textures are those for Earth and Mars as the Red Giant approaches them. There are base textures, bumps and spec maps for them and that one add-on is about 15 MB in total textures. Not terrible, but a bit high as textures go. The other 42 MB are all the other textures combined.

I really don't want to use LORES textures. I love the look of Earth and Mars that are created as the Red Giant destroys them (see Earth image in an earlier post on this topic above).

If anyone knows how to compress textures more than WINZIP will do, let me know. If this education thing gets launched, we will have to figure all of this out. In all, there are over 600 MB of separate add-ons used in my 6 activities to date.

Frank

[selden]

How about providing the "basic" activity with minimal resolution textures plus a highres "upgrade"? That might reduce the size enough so that more people would be willing to download the basic version and then persuade themselves to get the upgraded version, too.

I dunno what resolutions you're using, but don't forget that some older cards can't handle textures larger than "1K". Spending many hours downloading something that you then find you can't use is rather frustrating.

[fsgregs]

Grant:

It is my understanding that the first stars formed about 1 billion years after the Big Bang, which occurred about 13.7 billion years ago. The average life span of a main sequence star like our sun is between 10 and 11 billion years. Yellow Giant stars burn through their hydrogen and helium much faster. The result is a Red Giant in either case that with respect to our sun, would form about 11 billion years after the Big Bang. In the case of larger stars, a star would get to the Red Giant stage within 5 billion years or less.

Red Giants (based on my research), only last under 500 million years. They then run out of helium fuel and begin fusing heavier elements, causing them to explode in a series of nova explosions. The end-result is a planetary nebula and a White Dwarf in the middle of it. The sky is full of White dwarfs. They do not undergo any further fusion, but are just cooling off slowly in space.

I have read that it takes about a billion years or so for a White Dwarf to cool to a cold black dwarf. Thus, that would bring us to a maximum of 12 billion years, meaning that the sky should be filled with cold black dwarfs. Since we can't see them, we haven't yet found any, but .....

With larger stars, their life cycle is accelerated and they can reach white dwarf/neutron star stage within a few billion years at most. Obviously, they have done so, since the initial matter in the universe after the Big Bang was just H, He and a touch of Li. All the heavy elements that make up our Solar System has come from prior stars going supernova. In fact, our sun may be a 3rd or 4th generation star. Although the parent stars blew up, the neutron stars that have been left behind are all cooling and turning into black dwarfs, and are doing so far quicker than the 14 billion year age of the universe..

If I am wrong about this, let me know and if you could, drop a website link in the reply demonstrating it, so I can find out why my information is incorrect. Thanks

Frank

[granthutchison]

James Kaler is Professor of Astronomy at the U of Illinois with a specific research interest in dying stars. I quote from his "Extreme Stars":
"... the rate of cooling is terribly slow. In the entire history of the Galaxy, no white dwarf - not even one created in the Galaxy's earliest days - has had time to move off the HR diagram and become invisible. There are no 'black dwarfs.'"
For an online check of this statement, see Kaler's page at http://www.astro.uiuc.edu/~kaler/sow/star_intro.html and search for "black dwarf."

Grant

[granthutchison]

Ah, here we go: I knew I'd seen an estimate of the cooling time for a white dwarf somewhere. From the lecture notes of Prof Darren DePoy at Ohio State U http://www-astronomy.mps.ohio-state.edu/~depoy/courses/lecture.notes/extreme.html, this comes in at ~10Tyr, or 10,000 billion years.

A simple Google search on "black dwarf" and "age of the Universe" turns up a host of hits. The first three relevant and useful ones go like this:

http://imagine.gsfc.nasa.gov/docs/science/know_l1/dwarfs.html
"Because it takes billions of years for white dwarfs to cool, we don't think the universe is old enough yet for many, if any, white dwarfs to have become black dwarfs."

http://www.physics.hku.hk/~nature/CD/regular_e/lectures/chap15.html
"After it has radiated away all its residue energy, it becomes a black dwarf. However, the time taken is much larger than the age of the universe. So, we believe there is no black dwarf yet."

http://zebu.uoregon.edu/~js/cosmo/lectures/lec17.html
"However, the timescale to cool to a black dwarf is thousands of times longer than the age of the Universe."

Neutron stars are another matter, of course, but I haven't ever seen their theoretical cool remnants referred to as "black dwarfs."

Hope this helps.

Grant

[granthutchison]

Frank:
On another topic, over here I've dug out some detailed predictions of the expanded orbits of solar system bodies during the Sun's red giant phase for Apollo7 - all the orbital radii increase just a tad under two-fold as the sun drops in mass by a half. Hope you might think it would be worth making these changes for added realism.
The same paper I reference over on that thread predicts considerable outgassing from Pluto as it heats up - so as well as shoving them out to around 75AU or so, it might be worth shrinking both Pluto and Charon, and pushing Charon into a wider orbit. They're doomed to be kicked out of the solar system in a few hundred million or a billion years after the red giant phase, but that shouldn't prevent your little human colony. I'm quite glad the orbits expand as they do, since I now think my original back-of-the-envelope estimate placed the habitable zone too close to the red giant - as you'll see over on the other thread, it seems likely it's going to be out where Pluto and Charon are now placed, instead.

But I do understand if you think such wholesale reorganization of the solar system might be too much for your anticipated audience to absorb in a single sitting ...

Grant

[Guest]

You can use 7-Zip for compressing the add on. http://www.7-zip.org It has a better compression rate than WinRAR or WinACE. Sometimes 50% better. It's freeware and you can also create SFX archives for those who havn't got 7-Zip installed.

I hope this helps

(Sorry for my poor english. I'm from Germany )

[Guest]

Can't wait to DL it. Sounds very interesting.

[Rassilon]

Ah, here we go: I knew I'd seen an estimate of the cooling time for a white dwarf somewhere. From the lecture notes of Prof Darren DePoy at Ohio State U http://www-astronomy.mps.ohio-state.edu/~depoy/courses/lecture.notes/extreme.html, this comes in at ~10Tyr, or 10,000 billion years.

Dont hold your breath!
I for one always thought black dwarfs were another name for a black hole...