Also when you type thirdperson into console, you see that Gordon has a ponytail…no seriously!
If there was no air, wouldnt there be large amounts of pressure and coldness?
I think it’s pretty hard to deny that there’s air in Xen. As far as I know, any right-minded person has to accept that Xen has air and, to a lesser extent, that the air must be breathable, at least within limits.
Also, which Brighton are you from?
If there was no ‘air’ there’s be no pressure whatsoever. That’s kinda how air works.
dont get me wrong here, im not trying to be arsy or anything, but realistically Xen looks like it is in space, its defined as;
“A collection of asteroids hanging over a nebula”
so, it is in space,
“The key concerns for a human without protective clothing beyond Earth’s atmosphere are the following, listed roughly in the descending order of mortal significance: ebullism, hypoxia, hypocapnia, decompression sickness, extreme temperature variations and cellular mutation and destruction from high energy photons and (sub-atomic) particles” - Wiki
You would be in tempratures of up to -270°C and unable to breath.
each to their own though eh? 
They also cocked that up in my favourite film Sunshine.
Edit - Brighton in uk.
Xen has enough gravity for an atmosphere, I’d say. It has more gravity than the moon, so it has the possibility for atmosphere, anyway.
omg, this horrible thread have been laying dead for two months until i quoted myself by mistake .\ [align=center]
WHAT HAVE I DONE!!![/size][/align]
It’s tenuous speculation, especially since the creatures who survive and thrive on Xen can be transported, completely unharmed, to Earth and actually survive. If there were no atmosphere, there would be no creatures. Therefore you need to assume that there’s some form of atmosphere. It’s like Earth - you can’t see the atmosphere at night - all you see is space, and it appears as though there’s nothing between you and the stars you see. I think it’s much the same as with Xen.
Considering Xen is in an entirely different dimension, space for them might be full of air.
Objects don’t have to be a sphere to have an atmosphere. As long as there is enough mass to attract particles and keep them there, theoretically you could have a planet like this:
(I loved that show… :[ )
Picture explanation: Earth cracked into little pieces, pieces stayed together, and atmosphere stayed on it.
While that is true, most things with enough gravity to have an atmosphere are usually weathered into spheres by their own atmosphere. Also, no such giant mass can be seen anywhere in Xen, so why bring it up?
Don’t forget about the giant testicle/sac monster, the three armed floating babies, plants that stab you, flying mantas, and The giant/floating/energy shooting from its head/forcing you to teleport/baby-boss. 
Um, yes. I’m aware of all of this. I don’t see how it has any bearing on what I said.
that if there is no air, the pressure is enormous.
Well, that’s simply not true. And what you quoted didn’t prove your point. In fact, it states the opposite (i.e. my point). The air is what creates the pressure.
So, unless you are referring to the pressure inside your body pushing outward, then you are wrong. There is no pressure in space without atmosphere.
To get more pressure, you’d have to be in something more dense than atmosphere (air.) For example water:
1 Atm: Earth
0 Atm: Space
Simply because there is enough mass overall to attract and keep particles.
Drew my own this time:
Think kinda like that, except the picture loops whenever you look at the rock things.
agreed. NEGATIVE pressure on a object such as a pressurized object in space. The negative (i.e. sucking pressure i.e. deCOMPRESSION) pressure of the surroundings create a strain or pressure on an object under pressure
I think I now hold the record for mentioning the word pressure in a sentance.
In a nutshell: No air pushing in on an object causes the air inside it to push outwards ie, explosive decompression. Like a gremlin in a microwave!
All this talk about science is making me dizzy