Damn, that's a big, ugly promo blurb on that cover.
Otherwise it's a pretty good cover. At first I thought it was one of those unusual "friendly alien" covers, rescuing some American astronauts, contrary to the vast majority of "alien menace" imagery in comics and pop culture of the era, but looking closer I think those humans are captured prisoners of the alien. Damn sneaky aliens, can never trust them.
Also, Ditko's vision of alien architecture, in this case the giant floating space centre, presumably the space POW camp in the space war, in the background, is always a delight.