MICHELE NORRIS, host:
And since we're coming up on the Fourth of July, and every town's preparing better-than-ever fireworks spectaculars, we'd like to remind you of the single greatest manmade light show America has ever created, a show that has never been and we hope never will be equaled.
Here's NPR science correspondent Robert Krulwich with a story that begins in the summer of 1962, at the height of the Cold War.
ROBERT KRULWICH: So, where were you on July 9th, 1962, the night the U.S. blew up a massive hydrogen bomb in outer space?
Mr. CECIL COLE: Well, I was sitting next to our equipment. We set up our...
KRULWICH: Cecil Cole, at the time, was a research scientist for a Massachusetts company. He was working for the government on a lonely atoll way out in the Pacific Ocean.
Mr. COLE: And there were two or three others guys there with me. And we were standing there in the dark, it was pitch black at night, couldn't see a hand in front of your face.
KRULWICH: And in a few minutes, the U.S. would launch a powerful rocket high, high up - higher than the Earth's atmosphere - carrying a huge explosive.
Mr. JAMES FLEMING: This was 1.4 megatons.
KRULWICH: Which is a lot bigger than the bomb over Hiroshima, says science historian James Fleming.
Mr. FLEMING: A thousand times bigger. [POST-BROADCAST CORRECTION: Starfish Prime was 100 times bigger than the Hiroshima bomb, not 1,000.]
KRULWICH: So big that two thousand miles north, in Honolulu, people in hotels were getting together...
Mr. FLEMING: You'd sit on the roof with little colorful drinks.
KRULWICH: And have what the papers were then calling...
Mr. FLEMING: The rainbow bomb parties.
KRULWICH: And at Desoto Brown's house - he was eight years old at the time...
Mr. DESOTO BROWN: I do have a memory of going out on our porch, on the second floor of our house, and looking at the sky.
KRULWICH: Meanwhile, listening to a government transmission on that atoll, Cecil could hear somebody counting down.
Mr. COLE: And he went - five, four, three, two, one. And at that instant, the whole Pacific lit up like a flash bulb, just spot - you know, just like an electronic flash, bright - bright as daylight. If you could imagine night turning into mid-day for just a split second. And then the sky turned green for about a second. Wasn't expecting that, either.
KRULWICH: Did you see the green, also?
Mr. BROWN: Yeah, and I can remember yellow and blue...
KRULWICH: Yellow and blue in the sky?
Mr. BROWN: Yeah, yeah. A good portion of the sky had really vivid, unnatural bright colors - much different than a sunset would be.
KRULWICH: Because the radiation from that H-bomb created a rare, manmade extension of the Van Allen belt. There is a band of radiation that surrounds our planet. It was discovered by James Van Allen five years earlier. And on the day that he made his discovery, says Professor Fleming...
Mr. FLEMING: That very same day, after the press conference, he agreed with the military to get involved in a project to set off atomic bombs in the magnetosphere to see if they could disrupt it...
KRULWICH: Wait, wait, wait...
So, Professor Fleming says that he discovered, while working on a biography of Van Allen, that the great scientist was immediately willing to help bomb what he'd just found.
Mr. FLEMING: This is the first occasion I've ever discovered where someone discovered something and immediately decided to blow it up.
KRULWICH: The generals thought that the Van Allen belt might be like a highway where you could blow up a bomb in one place and then move the blast down the belt so it could be targeted, say, over Moscow. It was a half-baked idea but the Soviets tried it, too. From 1958 to 1962...
Mr. FLEMING: Both countries blew up a number of A-bombs and H-bombs.
KRULWICH: And the radiation from those bombs hung around in the upper atmosphere for a while and then gradually dissipated up there. But on the night of July 9th, the sky was oddly beautiful, with a curtain of red light that hung in the air.
Mr. COLE: It wasn't shimmering, though, it was just glowing red like a neon sign. And then it slowly disappeared, just faded away. And there wasn't any sound to this at all, it was entirely visual. There was no bang or thunder or anything, it was just visual.
Mr. COLE: But it was a breathtaking scene. I don't know how on Earth that could ever be captured in movies or...
KRULWICH: But was it scary or just - or was it - you're the 8-year-old...
Mr. BROWN: I'm not scared. I'm not thinking it's the end of the world. I'm not thinking I'm about to get blown up by a bomb.
KRULWICH: But, says Professor Fleming...
Mr. FLEMING: The blast was so big that it shut down part of the Hawaiian electrical network, it blew out some transformers. And so, it caused some disruption on the island itself.
KRULWICH: And it certainly changed Cecil Cole, the scientist who measured the blast.
Mr. COLE: I'm 74, and it's - I think about this every day of my life a little bit. It's one of those events that's definitely unforgettable.
KRULWICH: Shortly after the blast, Mr. Cole resigned his job and became a university professor. And is that because of what you saw...
Mr. COLE: Well, yeah, you know, I realized when I saw that thing go off that there really wasn't any safe place on Earth to test those things. There's just too much energy to just let it go bang in the atmosphere or anywhere on the planet. And I really just didn't want to participate in that anymore.
KRULWICH: And in fact, that blast, codenamed Starfish Prime by the military, was one of the last U.S. H-bombs ever blown up in space. The next year, the Soviets and the U.S. were working on a test ban treaty and so, the era of man-made light shows flashing white over the entire Pacific Ocean, that era may be over.
Mr. BROWN: I would like to think that that's the case, yes.
KRULWICH: That's Desoto Brown, Cecil Cole, they saw it.
I'm Robert Krulwich, NPR News.
NORRIS: And if you'd like to see what the sky looked like that night, we've assembled a video montage of raw footage - the weird green sky, the red curtain, and the great white flash - all at npr.org/krulwich - that's K-R-U-L-W-I-C-H.