Scholz's Star - 'Fly By'

[Stargazer_00]

I can't see a topic about this, which is surprising given the many questions it asks!

Easy to read

http://www.bbc.co.uk/news/science-environment-31519875

Source

http://iopscience.iop.org/2041-8205/800/1/L17/article

The story discusses the 'fly by' of a star, grazing our outer Oort cloud and it's effects on our solar system.

I find the frequency of this type of event simply amazing.  Every 100,000 years?  

It invokes so many questions, I had to read it all!

[Tinker1947]

That Star must be nipping  long a bit, its now 20 LY's away in 70,000 years...its to early in the day for me...

[Stargazer_00]

Yeah, low mass fast moving.  With a smaller brown dwarf companion.

What strikes me is, doesn't it have any planetary objects orbiting it?   Doesn't it have it's own variation of an Oort cloud?   Wouldn't these objects have come a lot closer to us than the star?

This doesn't seem to be addressed in the study from what I can see.

[michael.h.f.wilkinson]

Planets might be hard to detect in the presence of the brown dwarf. Besides, the presence of the brown dwarf might have perturbed any planetary orbits, jettisoning them out of the system, or even preventing them forming in the first place. Planet hunters prefer to look at single stars.

The speed at which this star is moving through the local star field is such that its own Oort cloud equivalent may have been stripped away. It may even have donated material to our Oort cloud. The deviant deuterium content of comet 67p/Churyumov-Gerasimenko could be explained by it coming from another source (pure speculation until we get data from more comets).

[Stargazer_00]

Interesting points.   I'm not sure it mentioned the orbital distance of the companion brown dwarf but I'd imagine it to be something 'Jupiter-esque' in size  given the small star it was paired with.  So you're right that it might have expelled other objects in it's system.

With regards to it's speed and the potential for that to strip it's oort cloud.  Maybe it's not moving very quickly at all and it's actually our system that's zooming along and we went through it instead.   

It's an interesting theory about donor materials as well.  I think I read an article that suggested the number of samples required to be sure of something, in this case the general composition of comets, is something like 25,000.   So we've a long way to go before anything conclusive can be recorded.  I suspect we'd have to be inhabiting the Oort cloud before that is ever likely.

there's alot of water out there so that might not be as stupid or far fetched as it sounds!

[Nigele2]

I found this rather exciting.  My first thought was is this thing wandering aimlessly?  When I first got into this stuff you get the feeling that everything orbits something be it earth around the sun, or the arm of our galaxy circling a black hole.  And that everything is expanding and moving apart.

But then you read that one galaxy will pass through another so clearly expansion doesn't mean everything is separating.  Then rougue planets that are starless.  And now rougue stars saying hello to other stars.  

So presumably there is a very very small chance the end of the human race will be when another visitor gets even closer.  Cool.

No chance I can locate these guys with my average telescope I suppose (assuming a cloudless night within the next 100,000 years)?

[michael.h.f.wilkinson]

One thing that struck me was that even at a mere 0.8 light year distance, the star was only mag 10.3, and would have passed unnoticed by any human observers at the time (Neanderthals and Cro Magnon at that time, I would guess)

[Stargazer_00]

One thing that struck me was that even at a mere 0.8 light year distance, the star was only mag 10.3, and would have passed unnoticed by any human observers at the time (Neanderthals and Cro Magnon at that time, I would guess)

Yes, I had exactly the same though.   One would think a sun passing that close would be something akin to a daytime supernova yet it appears we probably wouldn't even see it unless we'd been looking precisely for it.

Even using a domestic scope many people might miss it assuming it was something very far away instead of small and very close.  You'd only notice it moving if you were looking at it over a period of time.

[Cath]

The stories the Sun could tell us about past events would I'm sure be absolutely astounding, if only it could !

Still, just this one passing star is interesting

[SlyReaper]

Yes, I had exactly the same though.   One would think a sun passing that close would be something akin to a daytime supernova yet it appears we probably wouldn't even see it unless we'd been looking precisely for it.

Even using a domestic scope many people might miss it assuming it was something very far away instead of small and very close.  You'd only notice it moving if you were looking at it over a period of time.

I like to imagine it from the other point of view.  If there's a life-bearing planet in orbit around Scholz's Star, from their point of view, it would be our sun "buzzing" theirs.  And our sun would most certainly have been visible from their world, one of the brightest things in its night sky.  

[ronin]

Not sure how "often" this occurs, in one bit it says:

"Dr Mamajek thinks it's not uncommon for alien stars to buzz the Sun. He says a star probably passes through the Oort Cloud every 100,000 years, or so."

In the immediate next paragraph is:

"Dr Mamajek said mathematical simulations show such an event occurs on average about once every nine million years."

So which one, there is a fair difference. :rolleyes:

[TheMightyKong]

So if such an event happens every 100,000 years or so, I wonder how the Oort Cloud managed to stay intact over 4.6 billion years. Was it much denser in the past? Just how dense/extensive is it now?

If it still exists does that mean no larger stars have buzzed the Oort Cloud? Do all stars produce Oort Clouds? Perhaps interstellar space is populated by wondering comets pulled from their host stars.