# Multiple Star Systems in DP0.2

**URL:** <https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359>\
**Category:** Support\
**Tags:** dp0\
**Created:** [January 22, 2023, 6:20pm UTC](https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359 "2023-01-22T18:20:57Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![babel](https://sea2.discourse-cdn.com/flex002/user_avatar/www.rubin.community/babel/32/2085_2.png) [@babel](https://www.rubin.community/u/babel)\
**Post date:** [January 22, 2023, 6:20pm UTC](https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359/1 "2023-01-22T18:20:57Z")

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I can’t find a specific reference for this, so I just want to make sure: there are no multiple star systems in DP0.2, right?

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**Author:** ![DouglasLTucker](https://sea2.discourse-cdn.com/flex002/user_avatar/www.rubin.community/douglasltucker/32/1341_2.png) [@DouglasLTucker](https://www.rubin.community/u/DouglasLTucker)\
**Post date:** [January 23, 2023, 5:21pm UTC](https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359/2 "2023-01-23T17:21:21Z")

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Dear Bob,  
I don’t believe multiple star systems were explicitly added to the simulations, but I wouldn’t be surprised if random placement of stars on the simulated images occasionally yielded visual double or multiple stars – i.e., stars that just happen to lie on the same line-of-sight on the sky but are not physically associated with each other.  
Let me check with the DESC group to make sure…  
Best regards,  
Douglas

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**Author:** ![DouglasLTucker](https://sea2.discourse-cdn.com/flex002/user_avatar/www.rubin.community/douglasltucker/32/1341_2.png) [@DouglasLTucker](https://www.rubin.community/u/DouglasLTucker)\
**Post date:** [January 23, 2023, 9:23pm UTC](https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359/3 "2023-01-23T21:23:32Z")

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Update: So far, all with whom I have communicated with indicate that there are no explicit binaries/multiple star systems in DC2 (and this in DP0.2), and that “[t]here are no parameters in the original database that would handle the explicit binary information,” as far as anyone seems to remember. The general opinion is that all stars were simulated as single stars. But there may still be additional people who were closer to that part of the DC2 simulations weighing in later.

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**Author:** ![babel](https://sea2.discourse-cdn.com/flex002/user_avatar/www.rubin.community/babel/32/2085_2.png) [@babel](https://www.rubin.community/u/babel)\
**Post date:** [January 24, 2023, 4:34am UTC](https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359/4 "2023-01-24T04:34:43Z")

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Thank you Douglas! I just wanted to make sure.

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**Author:** ![DouglasLTucker](https://sea2.discourse-cdn.com/flex002/user_avatar/www.rubin.community/douglasltucker/32/1341_2.png) [@DouglasLTucker](https://www.rubin.community/u/DouglasLTucker)\
**Post date:** [January 24, 2023, 10:34pm UTC](https://www.rubin.community/t/multiple-star-systems-in-dp0-2/7359/5 "2023-01-24T22:34:27Z")

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You are very welcome, Bob!

Further update: I’ve received no more info from the DESC DC2 simulations folks; so I think it is pretty certain that there are no physical binary or multiple star systems represented in the simulated data: any apparent binaries/multiple star systems are just chance juxtapositions. So i am going to close this topic out (but we can always re-open it if needed.) Thanks!