Odd that the screenshot in the article isn't of the actual arcade game but rather the Atari 2600 port (which is granted a quite good port given the limitations of the 2600), but still.
But more importantly, since the article went on to describe the "octopus" and other aliens in some detail, I was looking at that picture trying to see those details. None of those aliens were quite as I remembered them. That Atari 2600 picture really doesn't do justice to what the article goes into detail about.