The Two-Second Star

The alert came in while Priya was complaining about the coffee.

Maya was not supposed to be at the observatory at two in the morning, but the road down the mountain was closed for the storm, and her aunt worked the night desk, and so here she was, curled in a rolling chair that squeaked, watching a graduate student named Priya scroll through feeds she said were nine-tenths garbage.

"Satellites see something flash," Priya had explained earlier, yawning. "They ping the whole network. Most of it is nothing. A hot pixel. A cosmic ray hitting the detector. We ignore almost all of it."

So Maya had been ignoring things for two hours. Then a box lit up green on the second monitor, and a soft chime played, and a line of numbers scrolled across.

Priya glanced at it and set her cup down.

"Huh," she said.

Maya sat up. "What."

"Gamma ray burst. Real one, probably. The satellite caught about two seconds of it." Priya was already typing. "Two seconds. That's it. It's over. Whatever did that is already done."

Maya watched the numbers. There was a distance attached to them, and the distance did not make sense to her, so she read it three times.

"That says billions," she said. "Billions of light years."

"Yeah." Priya pulled up a second window, a map of the sky with a small circle drawn on it. "That's normal for these. They come from way, way out."

Maya did the thing she did when a number was too big, which was to break it into smaller trues and stack them.

A light year was how far light traveled in a year. Light was the fastest thing. Billions of years of the fastest thing, crossing the dark, to hit a detector for two seconds while a graduate student complained about coffee.

"So it happened before," Maya said slowly. "The flash. It happened a long time ago."

"Before the Earth existed," Priya said. She said it the way you say a fact you have said many times. "Before the Sun, some of them. The light's just arriving now."

Maya looked at the little circle on the map. Somewhere inside it, a very long time ago, something had happened. She wanted to know how big.

"How much," she said. "How much did it let out. To still be that bright from that far."

Priya leaned back. This part she seemed to like. "Okay. You know the Sun."

"I know the Sun."

"The Sun's going to shine for about ten billion years total. Whole life. Start to finish. All the light it will ever make." Priya held up one finger. "A burst like this puts out more than that. More than the Sun's entire life. In a couple of seconds."

Maya waited for her to correct it. To say she had exaggerated. Priya didn't.

"That can't be a real sentence," Maya said.

"It's a real sentence."

Maya stood up. The chair rolled back and hit the desk behind her and she didn't notice. She was looking at the circle on the map, and then at the window, where the storm was breaking apart and a few stars were showing through the moving cloud.

She tried to stack it and couldn't. The Sun was the biggest thing she had. The Sun was so big that you were not allowed to look at it. The Sun ran the whole day, every day, the whole summer, warmed the whole ocean, and it would do that for ten billion years, and all of that, every second of it, poured into one pile, was less than two seconds of the thing that made the flash.

"Why so short," she said. "If it's that much. Why only two seconds."

Priya opened her mouth, then closed it. "We think it's a star collapsing. Or two dead stars hitting each other. The short ones especially, we're honestly still arguing about. Nobody's watched one up close. You can't. By the time you know it happened, it's finished."

"So you don't know," Maya said. Not mean. Just checking the edge of the thing.

"For the short ones? Not all the way. No."

Maya liked that answer better than she expected to. She had thought the biggest thing in the universe would be the most explained. Instead the biggest thing in the universe was a two-second question that the smartest people were still fighting over.

She looked back at the window. The clouds were thinning fast now.

"When it happened," she said, "was anybody looking?"

"At the burst? No. Nobody was anywhere. It was the early universe. No Earth, no people."

"So for billions of years," Maya said, "the light was just coming. And nothing was here to catch it. And it kept coming anyway."

"It doesn't need us," Priya said. "It just goes."

Maya thought about all the directions the light had gone that weren't this one. Most of it had missed. Most of it was still traveling, past the Earth, past everything, out into more dark, and it would keep going, and some of it would never touch anything at all.

And one thin thread of it had crossed the entire history of the world to arrive tonight, in the storm, at a mountaintop, on the one night the road was closed and she couldn't go home.

"Priya," she said. "How many happen. Per day. Somewhere."

"About one a day that we catch. Across the whole sky."

"So one happened yesterday."

"Sure."

"And one'll happen tomorrow. Way out there. And the light's already leaving." Maya pressed her hands flat over her mouth and spoke through them. "Right now. Some of them are already coming. And they won't get here for billions of years."

"Most of them, we'll never see," Priya said. "We just happened to be pointed the right way for this one."

The last of the cloud slid off the sky.

Maya went to the window. The circle on the monitor behind her marked a patch of sky, and she found the same patch through the glass, an ordinary dark square with three faint stars in it, nothing else, nothing moving.

The flash was already gone. It had been gone longer than the Earth had existed. She stood at the window and looked at the empty place where it used to be, still arriving.