Voyager275 Posted May 16, 2015 Share Posted May 16, 2015 Some evidence suggests that Sirius is in a binary relationship with the Sun. I think that this holds some truth. What do you think? Link to comment Share on other sites More sharing options...
Brotoro Posted May 16, 2015 Share Posted May 16, 2015 Seems unlikely. To be in a binary system, the stars would have most likely have had to form together. Sirius has a mass of around 2 solar masses, so if it formed at the same time our Sun did, it would already be a white dwarf. Link to comment Share on other sites More sharing options...
NovaSilisko Posted May 16, 2015 Share Posted May 16, 2015 [citation needed] Link to comment Share on other sites More sharing options...
Scotius Posted May 16, 2015 Share Posted May 16, 2015 At 9 lightyears? That's a heck of a distant relationship Maybe your source talks about both stars forming from the same nebula? Link to comment Share on other sites More sharing options...
K^2 Posted May 16, 2015 Share Posted May 16, 2015 At 9 lightyears? That's a heck of a distant relationship Maybe your source talks about both stars forming from the same nebula?Unlikely. See Brotoro's remark. If anything, there is indication that Sun has drifted far from other stars that started out in the same group. Link to comment Share on other sites More sharing options...
J.Random Posted May 16, 2015 Share Posted May 16, 2015 Isn't Sirius a binary system already? Link to comment Share on other sites More sharing options...
Voyager275 Posted May 16, 2015 Author Share Posted May 16, 2015 Sirius A and Sirius B would have the necessary gravity to span 8 light years. Also Sirius has been the target of great attention from ancient humans going so far as building objects that are always lined up with Sirius. Link to comment Share on other sites More sharing options...
maltesh Posted May 16, 2015 Share Posted May 16, 2015 (edited) According to the Wikipedia article, Sirius is approaching the solar system at about 7.6 km/s.The Escape velocity of Sirius at a distance of 8 LY is about 83 m/s.The Sun is not orbiting Sirius. Edited May 16, 2015 by maltesh Corrected magnitude and direction of Sirius' velocity. Link to comment Share on other sites More sharing options...
Drunken Hobo Posted May 16, 2015 Share Posted May 16, 2015 With a simple orbit on Universe Sandbox, the Sun would be orbiting Sirius at an average of 50m/s with an orbital period of 230 million years. Sirius is only about 200-300 million years old whilst the Sun is 4.5 billion years old. The Alpha Centauri system is half the distance and 2/3 the mass of the Sirius system, so would have a more significant gravitational effect on the Sun. It simply wouldn't make sense in any way. Link to comment Share on other sites More sharing options...
K^2 Posted May 16, 2015 Share Posted May 16, 2015 It's moving at less than 2,000 mas/year. That's half a degree per thousand years. To within precision everything was built at historical sites of 3k years past, it'd still match up, sure.But that still puts relative velocity at nearly 20km/s. W.r.t CoM, that puts it at nearly 5km/s. Whereas escape velocity of Sirius binary with respect to the same CoM is merely 100m/s. The difference is well over an order of magnitude.All of the current data absolutely disagrees with possibility of Sun and Sirius being gravitationally bound. But if you have measurement data that reduces velocity measurements by more than an order of magnitude, I'd like to see them.Edit: Ninja'd. Twice. I'm getting old. Link to comment Share on other sites More sharing options...
SelectHalfling0 Posted May 16, 2015 Share Posted May 16, 2015 I don't think we are in a binary relationship, but Sirius probably still has some affect on the Sun's orbit (like most nearby stars on eachother). Link to comment Share on other sites More sharing options...
YNM Posted May 16, 2015 Share Posted May 16, 2015 (edited) Source ?While the relative velocity between Sirius and Sun makes Sun might be gravitationally bound to Sirius is far too different to be bound to each other (at Sun's distance from Sirius, escape velocity (from Sirius) is ~ 80 km/s m/s, while relative velocity is just ~ 32 km/s), other than that I doubt that there can exist a binary that's 2 parsec away from each other in the disk portion of the Galaxy... not to mention age disrepancy. Edited May 16, 2015 by YNM Wrong reading ! Link to comment Share on other sites More sharing options...
maltesh Posted May 16, 2015 Share Posted May 16, 2015 Source ?While the relative velocity between Sirius and Sun makes Sun might be gravitationally bound to Sirius (at Sun's distance from Sirius, escape velocity (from Sirius) is ~ 80 km/s, while relative velocity is just ~ 32 km/s), I doubt that there can exist a binary that's 2 parsec away from each other in the disk portion of the Galaxy...Escape Velocity from Sirius at 8 LY is not about 80 km/s. It's about 80 m/s. 32 km/s is 400 times faster than escape velocity from Sirius at 8 LY. Link to comment Share on other sites More sharing options...
YNM Posted May 16, 2015 Share Posted May 16, 2015 Escape Velocity from Sirius at 8 LY is not about 80 km/s. It's about 80 m/s.Sorry ! Wrong reading of the input and output units ! Thought the escape velocity thing would churn up km/s, the same as proper motion one... Thank you ! Link to comment Share on other sites More sharing options...
Bill Phil Posted May 16, 2015 Share Posted May 16, 2015 Sirius is light years away, how can that possibly be a a set up for a binary relationship...?Alpha Centauri's binary system has a few stars that are much closer. Link to comment Share on other sites More sharing options...
Voyager275 Posted May 16, 2015 Author Share Posted May 16, 2015 So there's no possible way? How do we know if it is not possible? Humans are just now getting to know the Universe fundamentally. Also how do we know about Sirius system so well if we haven't been there. I love astronomy but I will admit there is always something new to discover and challenge our beliefs of our Universe Link to comment Share on other sites More sharing options...
Camacha Posted May 16, 2015 Share Posted May 16, 2015 So there's no possible way? How do we know if it is not possible? Humans are just now getting to know the Universe fundamentally. Proving it is impossible is hard, yet there is little evidence to suggest it is true either. I have heard this story before and the 'evidence' provided tends to be of a rather hoaxy nature. These stories tend to come from the same corner the electric universe, Planet X and similar stories come from.So, as many people have asked: where is the proof? Link to comment Share on other sites More sharing options...
Voyager275 Posted May 16, 2015 Author Share Posted May 16, 2015 Look Sirius has been idolized, is on the same plane angle of the Sun, and many ancient people built stuff to match Sirius thousands of years after they were gone. Explain how a pyramid shaft matches with Sirius 3,000 years after if it is not in some predictable relationship with the Sun Link to comment Share on other sites More sharing options...
Kryten Posted May 16, 2015 Share Posted May 16, 2015 It not noticeably moving relative to us is a predictable relationship with the sun. Link to comment Share on other sites More sharing options...
Camacha Posted May 16, 2015 Share Posted May 16, 2015 Look Sirius has been idolized, is on the same plane angle of the Sun, and many ancient people built stuff to match Sirius thousands of years after they were gone. Explain how a pyramid shaft matches with Sirius 3,000 years after if it is not in some predictable relationship with the SunIt not noticeably moving relative to us is a predictable relationship with the sun.This. It being idolized has nothing to do with binary or not, and its position can be explained in a number of ways, with Kryten posting one of the more obvious ones.Is there any actual evidence that can be called more than a simple and not unlikely coincidence? Link to comment Share on other sites More sharing options...
Jonboy Posted May 16, 2015 Share Posted May 16, 2015 Look Sirius has been idolized, is on the same plane angle of the Sun, and many ancient people built stuff to match Sirius thousands of years after they were gone. Explain how a pyramid shaft matches with Sirius 3,000 years after if it is not in some predictable relationship with the SunHow does ancient fascination with Sirius prove anything about an orbital relationship to the Sun? You're ignoring the obvious explanation, which is that it's the brightest star in the night sky. Of course the ancients were fascinated by it; start brightness was the only metric by which we could measure stars until parallax measurement was first proven in 1838. Link to comment Share on other sites More sharing options...
Commander Jebidiah Posted May 16, 2015 Share Posted May 16, 2015 You lot do realise that the name of our sun is Sol right? Link to comment Share on other sites More sharing options...
Robotengineer Posted May 16, 2015 Share Posted May 16, 2015 We need a sister planets program if it is a binary system... Link to comment Share on other sites More sharing options...
Camacha Posted May 17, 2015 Share Posted May 17, 2015 You lot do realise that the name of our sun is Sol right?In Latin, in English it is commonly called Sun or the Sun.The Latin name for the Sun, Sol, is widely known but is not common in general English language useSource. Link to comment Share on other sites More sharing options...
UmbralRaptor Posted May 17, 2015 Share Posted May 17, 2015 I'm going to guess that this binary thing was Voyager275 confusing Sirius being a binary star with the Nemesis hypothesis, etc? Link to comment Share on other sites More sharing options...
Recommended Posts