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Author Topic: Is it possible to have a binary system with twin stars carry planets?  (Read 14620 times)

KyrahAbattoir

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I've been trying for a few hours to build a binary system with "ideally" two stars of similar mass and size orbit around one another , so far i haven't been able to get a "flat" orbit and they tend to worm their way "forward" in space drawing pretty curves.

Problem is that i have the feeling that those orbitting curves are too unstable for any planets to manage to remain on orbit around those two suns, most of thems get slingshotted in outer space it seems, i think my binary system is just too "violent", altho for a good while i had an earth like planet "orbiting" the whole system.

Fun fact, it would be habitable only for a couple of years at a time while it is close of the star system, but it only took a few decades to get it slingshotted away...

Any suggestions?

These are my two stars in motion, in case anyone is interested:


atomic7732

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Re: Is it possible to have a binary system with twin stars carry planets?
« Reply #1 on: April 30, 2011, 10:28:37 PM »
1. Place two stars.

2. Use the select tool next to the add object button (dashed square)

3. Select both stars

4. Click "Make Binary orbit"

5. Click "Add Barycenter"

6. Create a planet

7. Select the planet and barycenter

8. Click "Make Binary orbit"

You now have stars A and B, and planet (AB)b.

Joshimitsu91

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1. Place two stars.

2. Use the select tool next to the add object button (dashed square)

3. Select both stars

4. Click "Make Binary orbit"

5. Click "Add Barycenter"

6. Create a planet

7. Select the planet and barycenter

8. Click "Make Binary orbit"

You now have stars A and B, and planet (AB)b.

Excellent advice, i had been trying to make one for ages manually! I could get the stars to orbit but not the planets... they would always eventually shoot away (seemingly disregarding gravity?) Wierdly they wouldn't slingshot but more just travel directly away from the stars...

Anyway thanks for the advice because this helped me too :)

lexman6

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Just tried myself, works like a charm. Although you need to have a good distance between the stars and the planets. First time, Venus crashed straight into a star and Uranus was shot out of the system. I loled.

Saturn is still going strong though, I guess thats because it was the only planet more than 1 AU from the stars.

chrag

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I dont think planets can form around a Binary star system... The gravitational waves would prevent any dust from accreting into anything significant! On the other hand... it would look ultra cool to have two suns!! :)

Naru523

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I dont think planets can form around a Binary star system... The gravitational waves would prevent any dust from accreting into anything significant! On the other hand... it would look ultra cool to have two suns!! :)

Actually it's possible.

Such as 61 Cygni, a triple star system.

atomic7732

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I dont think planets can form around a Binary star system... The gravitational waves would prevent any dust from accreting into anything significant! On the other hand... it would look ultra cool to have two suns!! :)
There are 3 known circumbinary systems (planets orbiting two stars), as opposed to many planets orbiting one star in a multiple star system. Actually... NN Serpentis (AB)b and (AB)c were discovered not too long ago. What is it two months?

Omnigeek6

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Weighing in:

Quote
1. Place two stars.

2. Use the select tool next to the add object button (dashed square)

3. Select both stars

4. Click "Make Binary orbit"

5. Click "Add Barycenter"

6. Create a planet

7. Select the planet and barycenter

8. Click "Make Binary orbit"

Something else optional, but useful is: 9. click "Balance Selected". You can now center the universe on Absolute Space and have the trails make more sense.


To the people trying to make planets in binary (or more) star systems, here's a good rule of thumb for stability: If the planet is orbiting one of the stars, the periapsis of the other star should be more than 5 times the apsis distance of the planet. If the planet is orbiting both stars, this should be reversed, i.e. the planet should be at least 5 times farther from the stars than the stars are from each other.
Note: This is apsis and periapsis, not SMA. The more eccentric your orbits, the more your SMAs will have to differ.

Of course, in a trinary star system, you may have to factor in both rules. For example, if you want to have two stars in a close binary, orbited by a circumbinary planet, and then have a third star farther out than the planet, then: (Assuming the inner stars have a combined luminosity of 1 sun) the stars should be closer than 30 million km, the planet should be about 1 AU out, and the outer star should be at least 5 AU out.

chrag

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I dont think planets can form around a Binary star system... The gravitational waves would prevent any dust from accreting into anything significant! On the other hand... it would look ultra cool to have two suns!! :)
There are 3 known circumbinary systems (planets orbiting two stars), as opposed to many planets orbiting one star in a multiple star system. Actually... NN Serpentis (AB)b and (AB)c were discovered not too long ago. What is it two months?

My small mind was not thinking of stars capturing each other in orbits... I stand corrected :)

Dan Dixon

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Thanks NeutronStar for the great instructions, Omnigeek6 for the "Balance Selected" suggestion, and to Naru523 for the link to Wikipedia. Welcome to the forums chrag. :)