“In the deepest sense, the search for extraterrestrial intelligence is a search for ourselves,” said Carl Sagan. Although as yet unfulfilled, the quest continues from the Kepler Mission to Tess and now via the ten 25-meter radio antenna dishes of the continent-wide Very Long Baseline Array (VLBA). Astronomers have announced the discovery of a Saturn-sized planet closely orbiting a small, cool star 35 light-years from Earth using the VLBA’s supersharp radio “vision”.
Today the European Southern Observatory (ESO) has released the first ever image of a multi-planet system around a young, Sun-like star accompanied by two giant exoplanets twenty-five years after Michel Mayor and Didier Queloz announced the first discovery of a planet outside our solar system orbiting a solar-type star in our home galaxy, the Milky Way using the Haute-Provence Observatory in southern France. The exoplanet, 51 Pegasi b, discovered using the Doppler spectroscopy technique, which measures wobbles of a star as a planet orbits around it, is a gaseous ball comparable with the solar system’s biggest gas giant, Jupiter.
A strange ice giant that can’t be explained by previous theory has been discovered by NASA Scientists using the exoplanet-sleuth Transiting Exoplanet Survey Satellite (TESS, which had “first light” on Aug. 7, 2018). The planet, TOI-849 b, is the most massive Neptune-sized planet detected to date, and the first to have a density that is comparable to Earth. The odd proportions of planet orbits a star about 750 light years from Earth every 18 hours, and is 40 times more massive.
There’s been increasing speculation that many of the Milky Way’s more than 4,100 known exoplanets might resemble the ocean worlds of Jupiter’s storied moon Europa and Saturn’s Enceladus. “So if we’re thinking about these places as being possibly habitable, maybe bigger versions of them in other planetary systems are habitable too,” says NASA’s Lynnae Quick about planets with oceans that may be orbiting many of our galaxy’s one trillion stars.
“Plumes of water erupt from Europa and Enceladus, so we can tell that these bodies have subsurface oceans beneath their ice shells, and they have energy that drives the plumes, which are two requirements for life as we know it,” says Lynnae Quick, a NASA planetary scientist who specializes in volcanism and ocean worlds, about speculation that many of the more than 4,000 known exoplanets might resemble some of the watery moons around Jupiter and Saturn. “So if we’re thinking about these places as being possibly habitable, maybe bigger versions of them in other planetary systems are habitable too.”
Andrew Siemion, director of the University of California Berkeley SETI Research Center, recently wrote in an email to The Daily Galaxy that “I suspect there are other intelligent civilizations in the Milky Way Galaxy– we just need to look!” Now, new calculations place an upper limit of 0.18 Earth-like planets per G-type star in our Galaxy, according to University of British Columbia researcher Michelle Kunimoto about six billion rocky, Earth-sized planets orbiting in the habitable zones of Sun-like (G) stars in the Milky Way.
