“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.
New research suggests that searches for extraterrestrial intelligent civilizations not only reveals the existence of how life forms, but also gives us clues for how long our own civilization will last, according to astrophysicist Christopher Conselice, based on the hypothesis that it takes 5 billion years for intelligent life to form on exoplanets, as it did on Earth.
Today’s YouTube episode of The Galaxy Report with two stories that alter our knowledge of planet Earth, our galaxy and the vast cosmos beyond. The first is a journey to the center of the Milky Way and the detection of strange, exotic objects by the UCLA Galactic Center Group. The second, a chilling warning from China’s philosopher of alien civilizations, science-fiction author Liu Cixin.
Hubble’s infrared eye unveiled an enormous flash from Milky Way’s black hole about 3.5 million years ago that lit up a portion of a massive ribbon-like gas structure called the Magellanic Stream of high-velocity clouds of gas torn out of the Magellanic Clouds hundreds of millions of years ago, extending from the Large and Small Magellanic Clouds through the Galactic south pole of the Milky Way. The flash ionized its hydrogen (enough to make 100 million Suns) by stripping atoms of their electrons. The radiation cone was surely witnessed by Earth’s early hominids, already afoot on the African savannas as the ghostly glow spread high overhead in the then unnamed constellation Sagittarius.
ESA scientists observe that it cannot be proven whether the particular cloud of dust and gas that gave birth to our Sun collapsed as a result of the collision with the Sagittarius dwarf galaxy, discovered in the 1990s to be orbiting our galactic home. It seems possible, they conjecture, that without the dwarf galaxy crossing paths with the Milky Way, Earth and life on it may not have been born.
