A Signal Under the Ice

The research station on Europa, one of Jupiter's moons, was small, cold and very quiet. Four scientists lived there for two years at a time. Their job was to study the dark ocean under miles of ice.

Kenji Mori, the youngest of the four, was the station engineer. One night, while everyone else was sleeping, he was checking the underwater microphones when he heard something strange: a short beep, then a long one, then two short ones. After a minute of silence, the same pattern came again.

Kenji woke the commander, Dr. Amara Okafor. She listened with her eyes closed. "That isn't the ice moving," she said quietly. "That's a signal, and it's coming from somewhere below us."

By morning, the whole team was awake and excited. Lena, the biologist, couldn't stop smiling. "If it's alive, this will be the biggest discovery in human history," she said. Tomas, the geologist, was more careful. "And if it's a machine, I'd like to know whose machine it is."

They sent their small robot submarine, Otter, down through the station's hole in the ice. For three hours, they watched Otter's camera on the big screen as it went deeper and deeper into the black water. The signal got louder and louder.

Then, in the light of Otter's lamps, they saw it: a long silver shape lying on a rock. On its side there were old, faded letters: "EUROPA EXPLORER."

"I know that name," Tomas said. "That was the first submarine anyone ever sent here. Mission control lost contact with it forty years ago."

Lena's face fell. "So it's just an old robot."

But Kenji was studying the signal on his computer. "Wait. These beeps aren't random. It's a code, and it keeps saying the same thing: data ready, data ready. It's waiting for someone to answer."

It took them two days to connect Otter to the old machine and copy its memory. As soon as the copy was finished, the beeping stopped. Most of the files were damaged, but one folder was perfect. It held the old submarine's last pictures, thousands of them.

The first pictures showed only rocks and dark water. Then, picture after picture, small points of blue light appeared. As the old submarine moved closer, they became clearer: tiny, soft creatures like glowing flowers, moving slowly along the rocks.

Nobody said anything for a long moment. Then Lena started to laugh and cry at the same time.

"Forty years," Dr. Okafor said softly. "It found them forty years ago, and it waited all that time for somebody to come and listen."

That night, the team sent a message to Earth. Kenji wrote the first line himself: "We are not alone, and we have an old friend to thank for it."

Before he went to bed, he sat at his computer one more time and sent a short signal down through the ice to the old submarine: one long beep and two short ones. It didn't mean anything in any code, but Kenji knew exactly what it meant: "Thank you."