'Sky' in the Bible

As they were still staring into the sky while he was going, suddenly two men in white clothing stood near them

and said, "Men of Galilee, why do you stand here looking up into the sky? This same Jesus who has been taken up from you into heaven will come back in the same way you saw him go into heaven."

And I will perform wonders in the sky above and miraculous signs on the earth below, blood and fire and clouds of smoke.