[QUESTIONS] Exploring black holes and neutron stars

[streki]

When I jump to a Black hole system, I emerge at less than 5 mm from the black hole.

When I jump to a neutron star system, I emerge at about 0.22 Ly from the star.

- If the gravity well of a black hole is so much greater (more dangerous) than that of a neutron star, how come I'm dropped so very much closer ?

- Is my FSD computer trying to kill me?


EDIT: Oops, wrong forum section ?

 

[777Driver]

It has nothing to do with gravity. It is all about the heat being emitted from the Neutron star.

 

[Ian Phillips]

EDIT: Oops, wrong forum section ?

Seems fine to me

 

[Flyto]

When I jump to a Black hole system, I emerge at less than 5 mm from the black hole.

5 Mm, I hope...

When I jump to a neutron star system, I emerge at about 0.22 Ly from the star.

- If the gravity well of a black hole is so much greater (more dangerous) than that of a neutron star, how come I'm dropped so very much closer ?

- Is my FSD computer trying to kill me?

Heh, you make a good point. Given that there's no gravity in the game, and that as such black holes are really safe right now, I suspect it's a pragmatic thing to help people get really close to BHs and see the prettyness. So long as you drop out of supercruise a few hundred km away, you can fly right up to ~40km from a BH without taking damage.
Do not try this with a neutron star

 

[janmb]

When I jump to a Black hole system, I emerge at less than 5 mm from the black hole.

5 millimeters would indeed be quite unhealthy lol

 

[streki]

Heat eh ?
Ok that makes sense
Thanks to everyone who answered.
Rep for all - giving it away like candy.

 

[Ziljan]

So long as you drop out of supercruise a few hundred km away, you can fly right up to ~40km from a BH without taking damage.
Do not try this with a neutron star

A black hole is the next stage of collapse if a star is too massive to become a neutron star, so yes, it makes no sense that a neutron star would be more dangerous than a Black hole. The tidal forces alone should start to rip the hull apart and decompress the canopy at close enough range. Never mind the x-Ray radiation damage. Maybe removing celestial body exclusion zones and flying into a black hole will be part of the planetary "landing" expansion?

 

[Murishani]

A black hole is the next stage of collapse if a star is too massive to become a neutron star, so yes, it makes no sense that a neutron star would be more dangerous than a Black hole. The tidal forces alone should start to rip the hull apart and decompress the canopy at close enough range. Never mind the x-Ray radiation damage. Maybe removing celestial body exclusion zones and flying into a black hole will be part of the planetary "landing" expansion?

While I agree black holes need to be a considerably larger threat, I was under the impression that if flying towards a body like a neutron star or a black hole, what kills you WOULD be the heat, you'd be cooked by radiation and the heating of your own ship from gravitational pressure long before the canopy popped or it crushed you like a beer can. I had thought the game was actually accurate in that respect. Is that not correct?

 

[Ziljan]

While I agree black holes need to be a considerably larger threat, I was under the impression that if flying towards a body like a neutron star or a black hole, what kills you WOULD be the heat, you'd be cooked by radiation and the heating of your own ship from gravitational pressure long before the canopy popped or it crushed you like a beer can. I had thought the game was actually accurate in that respect. Is that not correct?

It can't be the radiation. If radiation was the cause, then flying away would reduce damage, sitting still inside a corona would still cause damage, and flying towards a star would destroy your ship. Aparently, what kills you is actual physical material of the corona hitting your hull at relativistic speeds, which explains why moving in any direction hurts, and parking is fine. However, a neutron star doesn't have a corona. It is a stellar corpse that blew all of its material off into the interstellar medium, which is now light years from the dead star corpse. If players are immune to stellar radiation, which apparently we are since we can park freely inside a 1 million Kelvin corona, then there is no reason why a neutron star's luminosity would hurt a ship more than a black hole, they are almost the same thing in terms of tidal forces and their other hazards differ only by degree. One is a giant atomic nucleus, and the other is a supermassive point particle. Neither is safe.

You could make a case that intense magnetic field of a neutron star causes induction currents in the ships hull and power grid interfering with power distribution, heat dissipation, and turning the hull of the ship into a charging capacitor, and thus the central section into a heat generating resistor. But then the pilot would just die as the ferrous metal in his blood flew from his body... So who cares about the ship at that point?

Edit: i should add that I have not been to a neutron star yet, so I'm not certain that parking in normal space in close orbit is safe, as it is at other stars. If so, then ED deserves high praise for its consistency in terms of radiation dangers. Although, if we can block solar radiation inside a corona without our hulls, then mere lasers should have no effect on a hull.

Tldr ...so no, the game is not 100%, but more like 80% consistent in terms of physics. But it is still the most scientifically accurate space sim to date. I'm sure as the game advances, and features come online, it will only get more accurate and more compelling.

 

[iain666]

Tldr ...so no, the game is not 100%, but more like 80% consistent in terms of physics. But it is still the most scientifically accurate space sim to date. I'm sure as the game advances, and features come online, it will only get more accurate and more compelling.

I get the impression that they're striving for accuracy in what you see out there, but skimping on the accuracy of what going to see the real thing would do to you for reasons of game play.

 

[Murishani]

Edit: i should add that I have not been to a neutron star yet, so I'm not certain that parking in normal space in close orbit is safe, as it is at other stars. If so, then ED deserves high praise for its consistency in terms of radiation dangers.

Now I have something else Ill need to test when I get back to the bubble, I'm not playing with the destructive force of neutron stars with a week of exploration data in storage.

I guess I presumed that gravitational compression was acting upon our ship and heating it. Like how Jupiter radiates heat. So I assumed that we'd cook before the ship was actually crushed. I thought this because the temperature of your ship DOES rise (to a specific temperature and then hold) while parked near a black hole even if holding still, it then rises when you move. I think this whole mechanic deserves more investigation, unfortunately my knowledge of astrophysics is clearly way less than yours so I wouldnt know what I was looking at beyond the percentage on my heat gauge.

 

[Flyto]

I guess I presumed that gravitational compression was acting upon our ship and heating it. Like how Jupiter radiates heat. So I assumed that we'd cook before the ship was actually crushed. I thought this because the temperature of your ship DOES rise (to a specific temperature and then hold) while parked near a black hole even if holding still, it then rises when you move. I think this whole mechanic deserves more investigation, unfortunately my knowledge of astrophysics is clearly way less than yours so I wouldnt know what I was looking at beyond the percentage on my heat gauge.

There's no gravity in the game at all. Note how you can hover 50km from a black hole, or indeed in the corona of a star or a short distance above a planet, and stay still without the use of thrusters. So the damage isn't from that.

Ultimately, BHs and NSs aren't gonna quite make sense, because we're dealing with relativistic objects in a simulation without gravity.

With that said, I've always assumed that the mechanic is:
* you gain heat at a rate that varies inversely with your distance from a star, and your temperature increases when this heat gain exceeds your ship's ability to radiate it.
* The rate of heat gain relates to the temperature of the star's surface
* Neutron stars have a very high surface temperature, and therefore they are dangerous at a relatively large distance

That much all makes a certain amount of sense, and fits with what one generally observes - although I've never tried accurately measuring the heat gain to test the relationships. It's probably not quite accurate with neutron stars, because their radiation patterns tend to be more complicated than normal stars, but apart from pulsars, it may not be a million miles off.

Now, as to black holes.... a naked black hole has (practically) zero radiation coming off it[1]. That fits with the mechanic above, in that the surface temperature (insomuch as there is a surface or that it has a temperature) is zero. Therefore, no heat comes off it. Therefore, we can fly right up to one. If there were accretion discs then there should be radiation from them as they fall in, but it wouldn't make sense to have one without the other.



[1] AIUI Hawking radiation is pretty small in magnitude for anything but a tiny BH

 

[Murishani]

Therefore, we can fly right up to one.

Well you can fly right up to one, drop out of SC and park.
When you do this your temperature gauge rises to a certain point and then stops. If you don't move, nothing will change, if you begin to speed up or move around at this point however your temeperature skyrockets.
Since you're in subluminal speeds, Ziljans explanation of bodies striking the ship at relativistic speeds doesn't apply (in this case, totally relevant for SCing around stars or other bodies), and since its a black hole, their should be no temperature coming off of it as you said. So what is damaging us?

I know at some point we just have to shrug and chalk it up to game mechanics, but it would be nice to explain some of these phenomenon with some plausible explanation.

 

[Flyto]

Well you can fly right up to one, drop out of SC and park.
When you do this your temperature gauge rises to a certain point and then stops. If you don't move, nothing will change, if you begin to speed up or move around at this point however your temeperature skyrockets.

Are you sure? I flew all the way around a BH at a radius of about 40km a few weeks back, and stayed cool.

 

[Murishani]

Are you sure?

That was my experience at least, Ill have to find another hole and test again, but from what I remember I could get close, drop out of SC and not move, but as soon as I applied thrust I started to heat up. Ill get back to you.

Edit: I was mistaken. I jumped into a system with a black hole as the main body, immediately got dumped out of SC and parked it. After cleaning up my cockpit seat and checking to make sure nothing had exploded, I started to move around and you are correct, I was at 32 km at 51% heat, steady. I moved to 45.2 km and was at 44% heat, steady. I did not accumulate heat as I moved away. Now I should mention that generally in real space, I run at 19% heat, so that 32% was a pretty sharp spike up just from being near the hole.

What may have happened on my last incident in retrospect was I may have been running at a hotter baseline so the proximity of the hole may have pushed me over a heat threshold that my PP couldn't dissipate and started causing damage and my desperate flailing to get out of the hole just overheated me worse.

I suspect the heat rises the closer to the body exclusion zone you get and dissipates the further you get.

So while I didnt accrue further heat from moving, I did in fact get hotter just from being near the hole, so the question is why? The answer is probably "because game mechanics". I still have yet to test a neutron but that will have to wait.

 

[EddyRockSteady]

.....mI still have yet to test a neutron but that will have to wait.

They cook you faster than double - struck lightning if you move more than an inch exiting witchspace. No way you are sneaking up anywhere near those doom-domes.

 

[Ziljan]

There's no gravity in the game at all.
...
* Neutron stars have a very high surface temperature, and therefore they are dangerous at a relatively large distance

[1] AIUI Hawking radiation is pretty small in magnitude for anything but a tiny BH

Neutron stars are much fainter than our own sun. They are much hotter, but they are also much smaller, and that tiny surface area severely limits their radiation output. As a result, they are so dim they are almost as hard as black holes to detect directly. Neutron star binaries emit 1/3 or less X rays than black hole binaries. Neutron stars floating alone in space, with no accretion disk would be quite dim compared to any main sequence star unless you were very very close.

What makes neutron stars dangerous is that they emit mostly in x rays, they have deadly magnetic fields, they have an escape velocity of ~0.3 c, and their tidal gravity is as lethal as some black holes. However, thermal radiation from a Neutron Star is actually safer than the Sun's corona, assuming you have X Ray resistant hulls, which we must have, otherwise fuel scooping would be lethal.

...So while I didnt accrue further heat from moving, I did in fact get hotter just from being near the hole, so the question is why? The answer is probably "because game mechanics". I still have yet to test a neutron but that will have to wait.

excellent observation, perhaps there is some radiation modeled in this game after all.

 

[Murishani]

excellent observation, perhaps there is some radiation modeled in this game after all.

For further test data, it should be noted that when I dropped in at other stars, I was also hotter than my standard operating temperature, its generally in the low to mid 40 %'s. But no stars Ive been next to yet have gotten me as hot as a black hole did upon exiting witch space, Ill have to do more testing. Which brings me to:

They cook you faster than double - struck lightning if you move more than an inch exiting witchspace. No way you are sneaking up anywhere near those doom-domes.

Yeah I know neutron stars... sneaking up and getting out unscathed wasn't really the plan. I was hoping to come back to the bubble, buy something cheap and go cook myself in several types of astronomical bodies. You know, for science.

 

[gooddoc]

Yesterday i jumped into a BH system & BAM!!! immediately i got the old 'too close - emergency stop' & got thrown out of SC.

I thought Oh Dear - that's not good. Too my surprise though the temperature remained the same. I took no hull damage & just a little on a few modules (1%). I switched off all non essential modules, picked an object to SC to & jumped out, didn't even need to find the escape vector! The temps rose slightly but i got out without any more damage.

Now if i'd done the same with a Neutron star I'd have took massive damage. I was lucky i reckon

 

[Murishani]

The temps rose slightly but i got out without any more damage.

Your temps went up from spooling up the FSD right? Not from the hole itself?