Just how bright was the full force of the sun in hard vacuum?

But it looked as if we were walking out into hard vacuum.

Well, at least that joint should hold against hard vacuum.

I mean, how can you think if your brain is the equivalent of a hard vacuum?

There was something to be said for hard vacuum and free fall.

How long did it take a human being to die in hard vacuum?

Those in the star chamber did not hear anything as the small room behind the door was opened to the hard vacuum of space.

She knew he could tolerate hard vacuum, at least for a while.

In two hours he would be sucking on good hard vacuum, the kind some people paid money for.

All three of us would make a very short cold trip into hard vacuum.