In July 2015 Russian billionaire philanthropist Yuri Milner announced that his Breakthrough Prize Foundation would donate $100 million over the course of 10 years to fund the biggest SETI project ever attempted. Prior to this, the field of SETI had effectively been the pauper of the astronomical sciences, shorn of government funding and limping along thanks only to the generosity of public and private donations. At best, its global annual funding was $1.5 million. With Milner’s millions, everything has changed.
The Breakthrough Listen project, as it is known, intends to direct some of the largest radio telescopes in the world on a decade-long mission to find evidence of intelligent life. Also, being able to diversify has been crucial to SETI’s survival as a viable scientific field of study. This century is increasingly one of optical SETI — small telescopes and carefully calibrated photometers looking for pulses of laser light that may last mere fractions of a second. To this end, the University of California’s Lick Observatory on Mount Hamilton is lending its Automated Planet Finder, a 2.4-meter robotically-controlled optical telescope, to the Breakthrough Listen project to look for the flashes of powerful lasers that could be beamed our way. Laser signals do not disperse as quickly as radio waves and have a higher bit rate, meaning they can carry more information even in a short pulse. Furthermore, there is less inherent noise in the system because lasers shine at a single specific wavelength, with none of the background hiss present in radio.The downside is that optical lasers can be attenuated by dust and gas in the interstellar medium, which results in the dimming of the light.
See for further details: http://www.astrobio.net/news-exclusive/seti-reborn-the-new-search-for-intelligent-life/