Eta Carina Nebula is 1300Ly away from Eta Carinae?
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That's about close to how it is in real life. Eta Carinae is about 7500 ly from Earth, while the Carina Nebula is estimated to be somewhere between 6500 to 10000 ly away. It's two separate objects that are named similarly because they're in the Carina constellation.
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Yep - we're naming things purely on what direction they are in when viewed from Sol. Actual proximity is pretty random, there's a direction towards a constellation and we just name everything in that direction after the constellation. Constellations are all about our 2D perception of the night sky - correlation in 3D space is pot luck.
I should also note, so that people don't make the same mistake:
-The Carina Nebula is a large molecular cloud in the same manner as the Orion Nebula, California Nebula, etc. It is also sometimes known as the Eta Carinae Nebula.
-The other, dramatic nebula that's associated with the pre-supernova activities of the star Eta Carinae is more accurately known as the Homunculus Nebula, and is closer in size to a planetary nebula. If this is in Elite, it would be in the immediate vicinity of the Eta Carinae system, while the much larger Carina Nebula would be further beyond the system and the Homunculus Nebula when looked at from the direction of Earth.
I haven't out in that direction yet in the game, I'm just speaking from my layman's knowledge of astronomy
-The Carina Nebula is a large molecular cloud in the same manner as the Orion Nebula, California Nebula, etc. It is also sometimes known as the Eta Carinae Nebula.
-The other, dramatic nebula that's associated with the pre-supernova activities of the star Eta Carinae is more accurately known as the Homunculus Nebula, and is closer in size to a planetary nebula. If this is in Elite, it would be in the immediate vicinity of the Eta Carinae system, while the much larger Carina Nebula would be further beyond the system and the Homunculus Nebula when looked at from the direction of Earth.
I haven't out in that direction yet in the game, I'm just speaking from my layman's knowledge of astronomy
According to these wiki pages Homunculus is inside Carina, but Carina is only 230Ly radius...
Sorry, but the OP is correct. The real-life Eta Carina Nebula is brightly lit because it is being lit up by the super-bright star Eta Carinae. Out there in the real universe, the star Eta Carinae is right in the middle of the Eta Carina nebula.
They are not in exactly the same place in ED because the people who hand-placed the supergiant stars and the nebulae were not using a single, cross-referenced catalogue containing both stars and nebulae. The stars with their distances were in one list, the nebulae in another. The two catalogues they used had different values for the distance to Eta Carinae (modern astronomy does not have accurate distance figures for most objects beyond a thousand lightyears away from us). The star was placed at one distance, the nebula at another, and no-one ever checked to see if they logically matched up until it was too late.
Out there in real life, nebulae are usually only visible because a hot, bright star (or a group of them) is lighting them up. Imagine a single streetlight in the middle of a forest. From a distance, you can see the streetlight, and the trees immediately around the streetlight. But the only reason you can see those particular trees, and not all the other trees in the forest, is that those trees happen to be right next to the streetlight. In the same way, the only reason we can see the Eta Carina Nebula is because it's right next to Eta Carinae.
In ED, making nebulae light up in response to the surrounding and enclosed stars was considered way too mathematically complicated to model (Dr Ross on the recent livestream said as much), so they "cheated": nebulae simply glow on their own, independent of whatever the stars or other lightsources surrounding them might be. This does mean that for some nebulae, such as Eta Carina, they have become decoupled from their logical lightsource.
They are not in exactly the same place in ED because the people who hand-placed the supergiant stars and the nebulae were not using a single, cross-referenced catalogue containing both stars and nebulae. The stars with their distances were in one list, the nebulae in another. The two catalogues they used had different values for the distance to Eta Carinae (modern astronomy does not have accurate distance figures for most objects beyond a thousand lightyears away from us). The star was placed at one distance, the nebula at another, and no-one ever checked to see if they logically matched up until it was too late.
Out there in real life, nebulae are usually only visible because a hot, bright star (or a group of them) is lighting them up. Imagine a single streetlight in the middle of a forest. From a distance, you can see the streetlight, and the trees immediately around the streetlight. But the only reason you can see those particular trees, and not all the other trees in the forest, is that those trees happen to be right next to the streetlight. In the same way, the only reason we can see the Eta Carina Nebula is because it's right next to Eta Carinae.
In ED, making nebulae light up in response to the surrounding and enclosed stars was considered way too mathematically complicated to model (Dr Ross on the recent livestream said as much), so they "cheated": nebulae simply glow on their own, independent of whatever the stars or other lightsources surrounding them might be. This does mean that for some nebulae, such as Eta Carina, they have become decoupled from their logical lightsource.
Nope, unfortunately it's not there. Real shame IMHO.
I've actually made this point before, about 2 years ago during my first circumnavigation attempt. I would have HOPED that FDev would have done something about it by now.
It's semi reasonable in my mind for the Homunculus Nebula to be missing. From our vantage point on earth, the gas making up the nebula was ejected from Eta Carinae about 175 years ago, so we're seeing what it looks like at age 175. It's about 1300 years later in the Elite Universe, plus Eta Carinae in game is about 7700 light years from earth, so visiting Eta Carinae in game is the equivalent of travelling forward in time another 9000 years. In 9000 years, the nebula will have expanded by about 50 times, and likely would fade to almost imperceptibility.
But why wouldn't that be the case with many other planetary nebulae?