Blue Super-Giant Stars!

[Deathsoul097]

What would be the habitable zone around the average Blue Super-Giant, if a habitable zone exists around such stars?

How much radiation Would they produce?

Would a slightly smaller, Earth-like planet be able to sustain life in orbit around it?

I ask because in a novel that I have already mentioned in several other threads is being written, and I proposed that a nearby planet humanity colonizes orbits either a supergiant or a dwarf star. I mean come on, imagine waking up and seeing this on the horizon:

Edited December 8, 2013 by Deathsoul097

[Tommygun]

I thought those blue super giants had very short life spans of hundreds of millions of years?

If so I don't think they would have any native life, but maybe a terraformed colonized world.

I would also wonder how bad solar storms are around them.

[Deathsoul097]

The idea is that the planet is habitable but no complex life has emerged due to the short timeframe.

I was wondering the same thing, like the radiation and solar storms, and how they would differ from our star.

[Tommygun]

They do have higher solar winds too, which I would think would tend to strip off any atmosphere faster.

So maybe this type of world should have a thinner atmosphere than Earth?

[Warhorse]

There is some question as to whether planets can actually form around blue supergiant stars, as the radiation from them is so intense that it tends to vaporize anything that gets remotely close to them. There is also the issue that these stars only live for a few tens of millions of years, and stars tend to get brighter as they age, so the life zone, and indeed the zone where planets can survive, shifts rather rapidly. Assuming that you can get around all of that, the life zone for these sorts of stars is centred more than 200 AU out (which means the star, as seen from there, is probably little more than a point). Even at that distance, UV is going to be a MAJOR issue, because these stars are 25000 to 30000 times brighter than the sun, and far more of their output is above the visual range.

[Deathsoul097]

Awwwwww, It would have been so cool to have a planet orbiting a Blue Supergiant really close up. (I guess I could still do this, just have a small rocky, barren asteroid of dwarf planet with a heavily shielded base) Could a brown dwarf sustain life? That might be interesting also. OOH! Maybe a Brown Dwarf - Blue Supergiant Binary system! How about that! Maybe the Brown dwarf Pulls away a lot of the radiation, making it more hospitable!

Edited December 8, 2013 by Deathsoul097

[Scotius]

Pulls away how? It would have to be a black hole, and even then effect of bending the rays would be very localised. But...you can go with electromagnetic field angle, and hide your base close to dwarf's surface. Under the umbrella of its electromagnetic field. Would that be enough to shield the crew from giant's death rays? I don't know - but i'm sure views would be spectacular

[Deathsoul097]

Maybe that would work. (I meant the magnetosphere originally, anyway.) And maybe the planet would be in a low, semi synchronous orbit over the dwarf?

" but i'm sure views would be spectacular "

This is pretty much the only reason I thought of a Blue supergiant. Because they are essentially the epitome of epic-ness.

Edited December 8, 2013 by Deathsoul097

[Tommygun]

I don't think they are as blue as that picture would suggest.

Our sun is a yellow type star and it appears bright white to the eyes except at sunset and that has more to do with pollution.

A blue Giant might appear as white with just a very small hint of very light blue to the eyes, well just before your retinas burnout at least.

[Drunken Hobo]

Can always get around the radiation problem by having life deep underwater.

I think the most likely scenario for life would be an ocean planet/moon, although as others have pointed out, it'd be very difficult for one to form around a blue supergiant.

[Tommygun]

Well then how about a frozen ice world far away from the star with a thick dark ozone atmosphere.

I think it would have to be a big enough planet to have vulcanism to replace the atmosphere and a strong magnetosphere to help keep it.

Maybe a relatively warmer titan like world, but larger than Earth.

If you want to add some SciFi elements to it, have very slow moving giant ice worms tunneling under the ice.

Then have a whole ecosystem based around these ice tunnels like the under water black smokers in the oceans or cave systems.

The colonist could even use these tunnels for building their settlements in and transportation.

[lajoswinkler]

I don't think they are as blue as that picture would suggest.

Our sun is a yellow type star and it appears bright white to the eyes except at sunset and that has more to do with pollution.

A blue Giant might appear as white with just a very small hint of very light blue to the eyes, well just before your retinas burnout at least.

True, they pretty much look white.

As for the Earth-like planet formation, it would be very difficult, namely because of the short life span of such stars.

[jwenting]

radiation pressure would be so intense it'd exceed any gravitational forces trying to pull stuff together to form rocks, let alone planets.

[Warhorse]

Well then how about a frozen ice world far away from the star with a thick dark ozone atmosphere.

I think it would have to be a big enough planet to have vulcanism to replace the atmosphere and a strong magnetosphere to help keep it.

Maybe a relatively warmer titan like world, but larger than Earth.

If you want to add some SciFi elements to it, have very slow moving giant ice worms tunneling under the ice.

Then have a whole ecosystem based around these ice tunnels like the under water black smokers in the oceans or cave systems.

The colonist could even use these tunnels for building their settlements in and transportation.

Sorry, not going to happen. The planet (if one could form) wouldn't have enough time to cool down and lose its initial heat of formation before the star went supernova!

[Tommygun]

Sorry, not going to happen. The planet (if one could form) wouldn't have enough time to cool down and lose its initial heat of formation before the star went supernova!

Oh I forgot about cool down. OK a rogue planet captured from an older smaller star during the blue giant's formation.

Yes, I have too much free time on my hands this weekend.

[Scion]

Our star appears "white" because the sun is so bright - filtered down, it does appear to have a yellow hue, just as a red giant appears "red."

Blue-white supergiants would appear as an awful arc-light so bright that it would be intolerable to human eyes - but they do have a blue tinge to them (slightly).

A "habitable" zone means being far enough away from this sort of star to avoid  being roasted, either by heat (duh!) or radiations that would blacken living matter very quickly.

So, in essence, you'd be so far out there would be little heat to make such a world very desirable.  It would just be a rock in space.  Blue-white supergiants are not for man - or anything else.

God help you if you were around when it collapses into a type II super-nova.  Or it emits a GRB.

Edited October 21, 2017 by Scion
fergit somethin'

[Scotius]

Are you kidding? They are awesomely big and energetic furnaces - cooking Mendeleev Table's worth of elements with their fusion alchemy. Everything - you, me, oxygen we breathe and water we drink was once a part of a hot star rarin' to go Supernova

[YNM]

The radiation are mostly UV. I don't think you can live with that.

Also, they spew out all the materials that's needed to make the planets (and life) faster. So it's even unlikely if they'll have planets around them !

Edited October 22, 2017 by YNM

[PB666]

The blue giants are not only short lived but they evolve rapidly and produce tremendous amounts of ionizing radiation.

Rocky planets need dust,  the hydrogen that almost entirely makes blue stars is not associated with space dust. So that the only planets that could form are gas giants. Those that are close would burn away in the heat of the star.

My suspicion is that blue binaries would be separated by considerable distance due to the difficulty of forming blue giants.

 

[Azimech]

14 hours ago, PB666 said:

My suspicion is that blue binaries would be separated by considerable distance due to the difficulty of forming blue giants.

 

Your suspicion might need some tuning. The name Azimech is the alternative name for the Spica star system. These two blue giants orbit each other every four days.

https://en.wikipedia.org/wiki/Spica

[PB666]

33 minutes ago, Azimech said:

Your suspicion might need some tuning. The name Azimech is the alternative name for the Spica star system. These two blue giants orbit each other every four days.

https://en.wikipedia.org/wiki/Spica

I was talking about early deep blue stars.

 

[Azimech]

1 hour ago, PB666 said:

I was talking about early deep blue stars.

 

What exactly is a "deep blue star"? You're talking about Wolf-Rayet stars? And talking about early, surely Spica went through an early phase.

Apparently 40% of Wolf-Rayet systems are binaries. https://arxiv.org/abs/1604.01022

And apparently a close binary is no exception with Wolf-Rayet stars either.

http://iopscience.iop.org/article/10.1088/0004-637X/789/1/10/pdf

[YNM]

@Azimech

Stars of these size (O-B main sequence) are mostly only found inside star clusters (or at least, O-B association). Which isn't exactly a great place to found life - yes it sounds exciting from colonization standpoint with all the densely packed systems but the whole thing probably goes under the UV lamp every day, and under heavy irradiation every year or so. They can come in any number of pairs. And all of them is extremely young, which can mean there might not even be any organuc materials at all.

The only times it's possible to find these stars outside such systems is in high-velocity/runaway stars : basically stars that have been flung out of galaxy centers. As the counterpart in such interaction is a black hole, usually the whole thing's already old anyway, and it's going to go terrifying.

So yeah, I don't think there's any way you can have natural life evolution around these stars. You can always park near one, though. Just watch the fits.

[Azimech]

1 minute ago, YNM said:

@Azimech

Stars of these size (O-B main sequence) are mostly only found inside star clusters (or at least, O-B association). Which isn't exactly a great place to found life - yes it sounds exciting from colonization standpoint with all the densely packed systems but the whole thing probably goes under the UV lamp every day, and under heavy irradiation every year or so. They can come in any number of pairs. And all of them is extremely young, which can mean there might not even be any organuc materials at all.

The only times it's possible to find these stars outside such systems is in high-velocity/runaway stars : basically stars that have been flung out of galaxy centers. As the counterpart in such interaction is a black hole, usually the whole thing's already old anyway, and it's going to go terrifying.

So yeah, I don't think there's any way you can have natural life evolution around these stars. You can always park near one, though. Just watch the fits.

Yes, I know this. I just wanted to help PB666 with his suspicion :-)

[PB666]

Azi, you haven't a clue to what I am talking about.

HD 140283, these are the lowest metal stars that were abundant in the first 5 billion years of the universe,it is nonetheless a second generation star, this star get the name Methusela because of its  age. Earlier stars could not be formed accretion around dust, they only formed in superdense bodies of gas and were very difficult to form.  But when they spontaneously formed they typical did so creating new galaxies, and their collapse probably initiated GBH formation and allowed similar blue stars (2nd generation) in their wake. Because these stars were so difficult to form the situation of binary formation was all the more difficult. Unlike Spiza this star is 14.46 ± 0.8 billion years in age. I think consideration of Spiza as a life bringing star is not worthy of any discussion. The star is no-longer in its main sequence is very unstable it has an eliptoid shape and as it expands it will begin stripping gas from its companion star with a catastrophic out come. Such a system could never sustain life. Rather than having complex life stopping situation HD 140283 could have planets that could sustain life, such as at the bottom of an ocean.

There are two primary problems. First the first generation or stars (population III stars) unlikely had planets and certainly no rocky planets. So on this account life comparable to that on earth could not exist. The second problem is that the energies in these stars suffices to erode the atmospheres of smaller planets (as might have been the case with venus). Such a planet would have to be further out relative to luminosity than the earth.

The early second generation of stars has largely the same problem, gassy planets and smaller rocky planets.

For the most part the blue star phase of our universe is over, yes a few younger galaxies have active blue star formation. The the bulk of accreted mass in our universe lies in large galaxies with lots of red stars. There are very short lived and unstable blue stars that appear now, but its not like looking at a galaxy and seeing all blue stars. https://en.wikipedia.org/wiki/UDFy-38135539