Communications across the immensity of interstellar space could be improved by taking advantage of a star’s ability to concentrate and magnify communication indications. A team of graduate students at Penn State is searching for just these communication signals that might be taking advantage of our sun if transmissions were flying through our solar system.
A paper illustrating the technique, explored as part of a graduate course at Penn State covering the Search for Extraterrestrial Intelligence (SETI), has been approved for publication in The Astronomical Journal and is ready on the preprint server arXiv.
Massive objects such as stars and black holes lead the light to bend as it passes by due to the object’s gravitational pull, according to Einstein’s Theory of General Relativity. The warped space surrounding the thing acts relatively like a lens of a telescope, focusing and magnifying the light. This effect is called gravitational lensing.
“Astronomers have considered taking advantage of gravitational lensing as a way to essentially build a giant telescope to look at planets around other stars,” announced Jason Wright, professor of astronomy and astrophysics at Penn State. He taught the course and is director of the Penn State Extraterrestrial Intelligence Center. “It has also been considered a way that humans might communicate with our own probes if we ever sent them to another star. If an extraterrestrial technological species were to use our sun as a lens for interstellar communication efforts, we should be able to detect those communications if we look in the right place.”