In 2048, an encrypted message arrives from Sigma Draconis, nineteen light years away from Earth - the second in history. The first, unencrypted, was read by Dr. Sarah Halifax 37 years ago. She is still alive, and now she may have the key to the code. Together with her husband, she is undergoing a rejuvenation procedure; the procedure works with Donald, but fails with Sarah. And now the gap of biological age is widening between them, and Sarah has very little time left to reveal the message of the aliens... (fantlab.ru)

Amateur translation.