https://www.vice.com/en_us/article/88qmba/scientists-are-looking-for-very-powerful-alien-transmitters-hiding-in-space-images

The search for intelligent life in the universe is getting a major boost from the Breakthrough Listen Initiative, which is the most comprehensive attempt ever to detect alien communications and technologies. Funded by billionaire Yuri Milner, the initiative is currently scanning one million stars within our galaxy, the Milky Way, for signs of alien civilizations.

Now, a pair of scientists have demonstrated that this huge ongoing survey might serendipitously capture signs of aliens in even more remote locations, such as galaxies that appear in the background of images that are focused on stars in the Milky Way.