It was the classic question; you had two tasks to perform and one promised to be much harder and more unpleasant than the other. Did you tackle the t… - Charles Sheffield

The universe is all extremes. Monstrous gravity fields, or next-to-nothing ones; extreme cold, or heat so intense that solids and liquids cannot exist; multimillion atmosphere pressures, or near-vacuum.
Ice or fire. Niflheim or Muspelheim: the ancient alternatives, imagined by humans long before the Expansion.
It’s planets that are the oddities; the strange neutral zone between suns and space, the thin interface where moderate temperatures and pressures and gravity fields can exist. And if planets are anomalies, then planets able to support life are rarer yet—a zero-measure subset in that set of strangeness.
And within that alien totality, where do humans fit?

Could it wipe out life on Earth?"
"Oh, I very much doubt that. Single-celled and oceanic forms will presumably survive. But it might make life impossible for humans."
"Actually, that tends to be my primary concern. Sponges and oysters will have to take care of themselves.

Birdie cringed. If there was one thing worse than being a coward, it was being mistaken for a hero.