It was not too spectacular at first, partly because it was almost exactly beneath us—at the precise center of the sun’s disk—and so was merged into all the activity around it. If it had been near the edge of the sun, and thus projected against the background of space, it would have been truly awe-inspiring.

Imagine the simultaneous explosion of a million H-bombs. You can’t? Nor can anyone else—but that was the sort of thing we were watching climb up toward us at hundreds of miles a second, straight out of the sun’s spinning equator. At first it formed a narrow jet, but it was quickly frayed around the edges by the magnetic and gravitational forces that were fighting against it. The central core kept right on, and it was soon obvious that it had escaped from the sun completely and was headed out into space—with us as its first target.

Though this had happened half a dozen times before, it was always exciting. It meant that we could capture some of the very substance of the sun as it went hurtling past in a great cloud of electrified gas. There was no danger; by the tune it reached us it would be far too tenuous to do any damage, and, indeed, it would take sensitive instruments to detect it at all.

One of those instruments was the Observatory’s radar, which was in continual use to map the invisible ionized layers that surround the sun for millions of miles. This was my department; as soon as there was any hope of picking up the oncoming cloud against the solar background, I aimed my giant radio mirror toward it.

It came in sharp and clear on the long-range screen—a vast, luminous island still moving outward from the sun at hundreds of miles a second. At this distance it was impossible to see its finer details, for my radar waves were taking minutes to make the round trip and to bring me back the information they were presenting on the screen. Even at its speed of not far short of a million miles an hour, it would be almost two days before the escaping prominence reached the orbit of Mercury and swept past us toward the outer planets. But neither Venus nor Earth would record its passing, for they were nowhere near its line of flight.