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New Evidence That All Stars Are Born in Pairs

cfa.harvard.edu

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Re: New Evidence That All Stars Are Born in Pairs

#81

Post by averagewall »

jwfxpr wrote: post #38
ngoldbaum wrote: post #18

Earlier quoted context omitted.

This is silly semantics. Jupiter and the Sun both orbit the center of mass of the Jupiter-Sun system. The article is making the point that for Jupiter and the Sun this point happens to be just outside the surface of the Sun. It's much simpler to say "Jupiter orbits the Sun" than "Jupiter and the Sun both orbit the center of mass of the Jupiter-Sun system". You can think of the former as a shorthand for the latter.

Semantics aren't silly in science, nor in education. I don't think it's so uninteresting as to be worthy of ridicule. It is not, in fact, obvious to the layperson that the Jupiter-Sun System would have a barycenter that doesn't lie inside the mass of the sun. The casual mental model (and all physical models I've ever seen) of the solar system we all share puts a metaphorical or mechanical axis through the center of t…

You can't make a physical model of the solar system that has the axis outside the surface of the sun because if the radius of sun and planets was in the correct proportion to the distances of the planets, they would be too tiny to see. Nor would you see the microscopic offset of the axis. If the sun was grossly oversized compared to the orbits (as it usually is), then the tiny offset of the center of rotation would still be visually indistinguishable from being at the center of the sun.

Re: New Evidence That All Stars Are Born in Pairs

#84

Post by okket »

motyar wrote: post #63

I read it 'Paris'. I need some coffee.

Most other news/social media sites have a small picture and/or a blurb to set the context beyond the headline. Since this is not possible here, I'd suggest tags like "Astronomy", "Science" etc. to help alleviate the problem of confusing headlines (pretty sure this has been discussed before, but anyway...)

Re: New Evidence That All Stars Are Born in Pairs

#85

Post by poizan42 »

pc2g4d wrote: post #32
gpvos wrote: post #5

Earlier quoted context omitted.

Not impossible, but rather unlikely. According to TFA, the partner star was much further out. Also, gas giant planets Jupiter's size are fairly common I thought (this knowledge may be outdated).

TFA? I'm getting "The Force Awakens". Or "Teach For America".

Well, it's the first result on urban dictionary: http://www.urbandictionary.com/define.php?term=TFA

Re: New Evidence That All Stars Are Born in Pairs

#86

Post by kashyapc »

grogers wrote: post #77
MarkMc wrote: post #72

Earlier quoted context omitted.

I read it as 'Paris' too. Actually I expect this is a very common error. "Born in $place_name" has a much higher base frequency than "Born in Pairs", so our System 1 brain screams "Paris!" until System 2 kicks in.

For me it was the casing. We aren't​ used to seeing "Pairs" capitalized, especially so since it is not the first word in the sentence. Paris however, will always be capitalized, so the brain autocorrects to the wrong word. Even though the title is in headline-case, it still fools you.

Yep, you hit the nail -- it's the casing, indeed. Much like other humans here, I read it 4 times, and still got stumped until I saw the comments section. (While coffee is next to me, and Paris is almost a stone's throw (3 hr train) from where I live.)

As you could imagine, clicked it purely because of my brain going: "What is that non sequitur at the end of the title?"

Re: New Evidence That All Stars Are Born in Pairs

#87

Post by dotancohen »

Razengan wrote: post #45
jnordwick wrote: post #2

Could Jupiter have been a failed pair?

Related question(s): Do stars ever look like Jupiter/gas-giant planets at some point during their formation? Can planets like Jupiter "pull in" enough matter to "ignite" and become stars in the future?

Excluding the Sun, there is not enough mass in the entire solar system to ignite Jupiter. Therefore, barring interaction with another star system, the answer is no.

Re: New Evidence That All Stars Are Born in Pairs

#90

Post by jwfxpr »

averagewall wrote: post #81
jwfxpr wrote: post #38

Earlier quoted context omitted.

Semantics aren't silly in science, nor in education. I don't think it's so uninteresting as to be worthy of ridicule. It is not, in fact, obvious to the layperson that the Jupiter-Sun System would have a barycenter that doesn't lie inside the mass of the sun. The casual mental model (and all physical models I've ever seen) of the solar system we all share puts a metaphorical or mechanical axis through the center of t…

You can't make a physical model of the solar system that has the axis outside the surface of the sun because if the radius of sun and planets was in the correct proportion to the distances of the planets, they would be too tiny to see. Nor would you see the microscopic offset of the axis. If the sun was grossly oversized compared to the orbits (as it usually is), then the tiny offset of the center of rotation would s…

Absolutely, I'm not criticising the construction of solar system models. I'm simply pointing out that if you lack a deeper understanding of the system they represent (or don't interrogate your understanding adequately), the simplifications of any model can quickly become understood as truth.
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