'required': ['color'],
Temperatures fell to freezing, food and water were rationed. It was days before they limped back to the fringes of Earth's atmosphere. They climbed back aboard the Odyssey and prayed the heat shield had not been damaged.
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"But you must keep up the exercise regime. Because you're staying fit in space, not for space itself, but for when you return back to the punishing gravity environment of Earth. Those first two or three days back on Earth can be really punishing."
While working on this over the last year, I was constantly looking for good tests to check my renderer against.