If you’ve ever watched any of the numerous videos available on the web of nuclear-weapons tests perhaps you experienced one of more of these reactions, especially with the big ones —hydrogen bombs:

Don’t those tests do permanent damage to the earth? Don’t they, I don’t know, scar it or something? If the government had to develop nuclear weapons, couldn’t they have been tested in outer space?

Of course, at the time that nuclear weapons were developed, the capability to launch missiles into space didn’t exist. Even if it did, space tests were of limited use to nuclear scientists because nuclear weapons behave differently in space than on earth where, of course, they would be used.

Eventually, though, before the Partial Test Ban Treaty ended them in 1963, the United States and Russia each tested a series of nuclear weapons outside the atmosphere — one, by the United States, 335 miles from earth. Besides the difference in appearance, such as an aurora-like effect in space as opposed to the earth’s mushroom cloud, the electromagnetic pulse that the nuclear weapons emitted were hard to control and endangered satellites orbiting the earth at that time.

Meanwhile, when nuclear weapons were first tested, scientists — some, anyway — must have swallowed their gut feelings that the planet was being irretrievably damaged by the tests in ways that were difficult to quantify. But, if, like me, you can’t help suspecting that the atmosphere was seriously seared, the following will reinforce your fears.

While in the navy in 1956, Robert Osborn, who maintains the website Words from the Wildernesse, witnessed the hydrogen bomb tests in Bikini Atoll. He describes the aftermath of one of them.

The cloud was sharply defined, like a thunderhead, and had a fluorescent, amethyst colored glow, which tinged toward a dark red. It is impossible to communicate the scale of the cloud. . . . We stood there in silence, looking at the cloud and quietly commenting on the colors. On the right side, close to the cloud, we could see two bright, stationary lights. They were visible for a short while, then they faded. . . . We were quite curious about the mysterious lights we saw beside the cloud. About a week or so after the shot, I was speaking to one of the scientists that had been aboard. He said they also had been puzzled by the appearance of the lights. They finally concluded that what we saw were two bright stars, essentially as we would have seen them from outer space. Apparently, the heat of the explosion was so great that it literally burned away the atmosphere around the fireball.

Call it what you will — a hole in the sky, a rent in the very fabric of existence — a nuclear war could leave the heavens in tatters like a flag that’s been through a battle.