"Star system" and "solid mass system"

[WinkAllKerb'']

just out of curiosity is ther some known system with a solid "dead" mass in their center and no fusion reactor star 

and if yes any serious ratio of said amount of such system ?

[Gaarst]

There have been planets discovered around star remnants (white dwarfs and neutron stars mostly). In fact, the first exoplanet system discovered orbits a pulsar (rapidly rotating neutron star) because pulsars rotations are known to be extremely periodic and small gravitational perturbation can be easily detected.

I don't know what proportion of exoplanets orbit non-fusing bodies, but the ones discovered are subject to detection bias anyway. AFAIK the mechanisms that lead such systems to form are not well known and no reliable models exist to give an estimation of this proportion.

[pincushionman]

Probably possible. Brown dwarfs spring to mind. Do those count as "dead" for your purposes?

[WinkAllKerb'']

hum thks was looking at this from both of your answer just before posting:

https://en.wikipedia.org/wiki/Hertzsprung–Russell_diagram
 

was thinking something "dead" like let's say our moon but much bigger middle of a system, what i m curious here is 3 ratio:

@center+@a system:
%%energy provider the biggest
%%not the biggest
%%energy inert

and forgive my autistic spelling
 

Edited February 4, 2017 by WinkAllKerb''

[p1t1o]

If there were, it would be incredibly difficult to spot from interstellar distances. White dwarfs and neutron stars we can detect because they are still quite hot, a "dead" rocky mass? Not so much. We can hardly spot these sorts of bodies in our own neighborhood, forget multiple lightyears away.

[kerbiloid]

They call this a rogue planet.
So, its mass would be like a frozen Superearth mass, but less than ice giant (as the latter would never be really solid due to hydrogen).

So, maybe 4-5 Earth masses is an upper limit.

Its moon, probably would be ten times less (otherwise how would it be formed or captured).

So, up to a 4..5earth Superearth with 0.5earth Supermars orbiting around.

[Allocthonous]

Maybe a Sub-brown dwarf is what you're looking for? No fusion going on, still big enough to snag a respectable amount of satellites. I don't know if those satellites would be moons or planets, because that sounds like it could get confusing really fast.

As kerbiloid mentions, these could be considered a type of rogue planet.

[WinkAllKerb'']

(( thks for the entries peops ^^, gonna keep on brainstorming around that ))

[insert_name]

While such a system is physically possible it would emit little radiation meaning it would be difficult to detect

 

[WinkAllKerb'']

i hum, i do wonder if we ever detected rotating planet (with a still active core)  around something " " ""dead"" " " (harder to detect than the system center itslef due to spectrum thingies)  then ?

Edited February 6, 2017 by WinkAllKerb''

[YNM]

The first extrasolar planet to be discpvered was around a pulsar, a fast-spinning lump of matter so dense.

Then there are brown dwarfs with rocks around it, as well as lone planet/brown dwarf limbo.

Which one's more often ? I'm inclined to say the later. Even a tiny rock around another rock somewhere in deep space could be counted as a system, no ?

Edited February 7, 2017 by YNM

[kerbiloid]

Formally, pulsar's crust is solid (in terms of statistical physics).

[Vanamonde]

Something that wasn't fusing would not create a solar wind to disperse the cloud from which it formed, and would be hard to see from outside the cloud. External influences would eventually disperse the cloud, I suppose. 

[p1t1o]

8 hours ago, Vanamonde said:

Something that wasn't fusing would not create a solar wind to disperse the cloud from which it formed, and would be hard to see from outside the cloud. External influences would eventually disperse the cloud, I suppose. 

Depends on the origins of the non-fusing object, if it is an object that has been ejected from its original location for example, or if it is a remnant that has already blown clear its local region.