Everyone said don't throw it backwards. So first thing I did was throw it backwards. Second thing I did was restart my browser.
The game shouldn't crash when you throw an airplane backwards. I know I just poked my eye out, but that doesn't mean the universe will explode.
So... You weren't kidding about not going backwards.
When you stall, it says hit SPACE, but you can actually press anything. Just give your keyboard a quick swipe: "qwertyuiop" and away you go! Thumbs up!
General strategy for getting lots of space stars (or at least how I got it): Max out upgrades. Pick up plane, go to bottom left corner, then throw quickly towards the top (try not to throw backwards). Immediately hold left and space, so you should fly close to straight up. When you have about ~1 bar of fuel left stop using engine. You should stall. Use emergency stall, now you're flying horizontal at some crazy high altitude and you can use the rest of your fuel to aim for stars.
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