Celestia Forums

Hey Everybody, I'm an English student who is studying in France (1S pour ceux qui s'y connais un peu) and I found out about this amazing software during a school trip to a science fair.
The aim of this trip was to help us with our TPE: Travail Personel Encadr?©, the French equivalent of a Research Project.

We met a astrophysicist who was passionate about this software and warmly recommended that we try and integrate it into our 'End Result'. Looking for every helping hand that we could get, we jumped at the chance.

Our actual project is based on the theoretical/physical existence of Black Holes and we've decided to look at what it would take for our Sun to transform into said object.

We want to integrate a small video/simulation into our project and I was wondering how we would go about Scripting this progression in the life of our sun


Following on from this image, if we consider that the requirements for the formation of a Black hole are based on the mass (1.4 solar masses I believe) then we could envisage the collision of our Sun with another Star or another theoretic addition of Mass to the White Dwarf, and therefore perhaps creating a Black Hole.

Thanks
Satum Out

Salut!

You should dig a bit the forum, Vincent has done a script recently showing the evolution of the Sun. It don't turn into BH but at least you will find a part of what you'd like to see...

First off Welcome to Celestia.

Unfortunately at this time stellar evolution is not supported, however with some advanced scripting techniques, it might be possible to create a simulation. I will leave that for more experienced people to explain.

When the sun becomes a white dwarf, it will only have about 60% of its current mass. The remaining 40% will have been ejected during the final stages. In order for a black hole to form from the remains, the second white dwarf would have to make up the difference in mass. The seconds star would need to be about two solar masses originally (~1 solar mass in the white dwarf phase). Providing that the collision does not eject a substantial part of the mass away, there should be enough mass to create a black hole. It also should be noted that the collision has to be with like objects (either 2 dwarf stars with between 2-3 solar masses or two white dwarfs with 1.4 solar masses combined) the reason being is that if a white dwarf hit a regular main sequence star, do to the difference in density the white dwarf would plow through the star as if it was not there. The star would explode do to the imbalance in pressure created due to the white dwarf.

The real fun is what happens to the planets. Some of them get engulfed, others have their orbits expand due to mass loss from the Sun. This could make the system "dynamically young", and result in a few strong planet-planet encounters kicking worlds all over the place.

Detection of planetary systems around white dwarf stars would be very interesting...

ElChristou wrote:Salut!

You should dig a bit the forum, Vincent has done a script recently showing the evolution of the Sun. It don't turn into BH but at least you will find a part of what you'd like to see...

Pardon me, but what search terms would one use? Using "solar evolution" and "sun's life" among other search terms leads to a slew of unwanted search returns.

Hi,

As reported by Chris (ElChristou), I'm currently working on an addon about the future of our Sun. Thanks to the object:setradius function I've added recently to celx scripting, this addon will show a dynamic evolution of the size of the Sun (main sequence -> subgiant -> giant -> white dwarf with planetary nebula). It will also show the M-Sun engulfing Mercury (and Venus ?), and the orbit change of (Venus ?), the Earth and Mars.

I'm not finished yet, but I may post a first beta-version soon in order to get feedbacks about the scientifical accuracy of the scenario and the quality of the addon itself...

So, stay tuned !

MKruer wrote:Providing that the collision does not eject a substantial part of the mass away, there should be enough mass to create a black hole. It also should be noted that the collision has to be with like objects (either 2 dwarf stars with between 2-3 solar masses or two white dwarfs with 1.4 solar masses combined) the reason being is that if a white dwarf hit a regular main sequence star, do to the difference in density the white dwarf would plow through the star as if it was not there. The star would explode do to the imbalance in pressure created due to the white dwarf.

What's the probability of such a collision with the Sun?

- Hank

Vincent, just curious, the "object:setradius function" can increase/decrease the radius of an object with fluidity or by steps?

hank wrote:

MKruer wrote:Providing that the collision does not eject a substantial part of the mass away, there should be enough mass to create a black hole. It also should be noted that the collision has to be with like objects (either 2 dwarf stars with between 2-3 solar masses or two white dwarfs with 1.4 solar masses combined) the reason being is that if a white dwarf hit a regular main sequence star, do to the difference in density the white dwarf would plow through the star as if it was not there. The star would explode do to the imbalance in pressure created due to the white dwarf.

What's the probability of such a collision with the Sun?

- Hank

So low that it is effectively nill. If I remember correctly when the Milky Way and Andromeda collide, it is thought that only a few hundred stars will actually collide despite there being between 200-400 billion stars in each.

Fenerit wrote:Vincent, just curious, the "object:setradius function" can increase/decrease the radius of an object with fluidity or by steps?

With a total fluidity !
I'll try to post a first beta version of the addon tomorrow...

Vincent wrote:

Fenerit wrote:Vincent, just curious, the "object:setradius function" can increase/decrease the radius of an object with fluidity or by steps?

With a total fluidity !
I'll try to post a first beta version of the addon tomorrow...

Yeah! Be the calm with you, Vincent. Take the time required; the important is that it will work.

Thanks guys, Sorry for the delay in answering to your posts, but school's demanding at the moment and I've been awol from my PC ^^

Vincent wrote:With a total fluidity !
I'll try to post a first beta version of the addon tomorrow...

Excellent Vincent, I can't wait to get a look at this, Keep me updated!

Thanks also to everyone else's answers especially Mkruer who's info I'm definitely looking at working into our project!

Satum wrote:Thanks guys, Sorry for the delay in answering to your posts, but school's demanding at the moment and I've been awol from my PC ^^

Vincent wrote:With a total fluidity !
I'll try to post a first beta version of the addon tomorrow...

Excellent Vincent, I can't wait to get a look at this, Keep me updated!

Thanks also to everyone else's answers especially Mkruer who's info I'm definitely looking at working into our project!

Here is a good analogy of the dynamics between our sun and a white dwarf.

Sun Density is 1.42 g/cm?? or ~ 1420 kg/m??
White Dwarf density is 1,000,000 g/cm?? or 1,000,000,000 (1 billion) kg/m??

If the Sun was the size of a trash bag full of air (diameter of 1m) a white dwarf would be the size of a pea (1cm) and weight a ton (1000kg)

Also there was something a while back on the Discovery Channel that had an animation of the impact. Basically as a white dwarf approached our sun it would begin to distort into a egg shape. (see Roche lobe) Once the white dwarf impacted the surface of the sun the surface would follow the white dwarf into the center, much like pushing your finger into a pillow. Once the white dwarf reached the center the sun, it would literately turn itself inside out, causing the sun to explode. Interestingly enough, depending on the age of the star, not that much mass would transfer from the sun to the white dwarf. I don?€™t have exact numbers but it would probably be less then 1%

Hi,

A first beta version of "The future of our Sun" addon is available here:
http://celestiaproject.net/forum/viewtopic.php?t=11593

Excelent I'm going to get and Download it straight away, it looks AMAZING Vincent!

Thanks for all your help, this is going to hellp me so much. I'll keep you guys updated on our progress.
And if I may be so bold, if we enconter any questions that need a little bit more knowledge to answer them, may I ask you guys?

Thanks Again
Satum

Satum:

Welcome to the forum.

FYI, an add-on detailing the life cycle of stars has already been done and can be found in the education section of the motherlode. It is part of the Educational Activities series, a set of 12 journeys through Celestia space that have been written to teach viewers/users about our universe. One of those journeys is called the Life of Stars, and can be found here as Activity 6:

http://www.celestiamotherlode.net/catalog/educational.php

It shows the complete life cycle of our sun, and also then covers the life of a large star, detailing its birth as a nebula and its death as a Black Hole. In fact, there are three black holes in the Activity. It comes with its own set of detailed add-ons, totaling over 100 MB.

This is not a short script, but a detailed voyage through Celestia space requiring at least 2 hours to complete.

Feel free to download the activity and take the journey. Note that you will also need to download a special version of Celestia 1.4.1 called "Celestia-ED". Details on on the above website link.

Regards

Frank

Excelent, I'll get and download it straight away, But either way 2 hours is a little long even for an educational activity, I'll have to film the bits that interess us. But in the long run I think that all this help is definetly helping me get cracking on this project. We're moving ahead and we hope to be done before christmas.

Thanks again, and any additional info will be greatly appreciated.

Satum Out

Nice work. That would be cool if somebody added "Metamorphosed" Solar system planets as well.