“Historically, our assumption has been that the region around Jupiter is fairly empty, cleaned out by the giant planet’s gravity, but our results teach us that there is a region that is constantly being fed,” said Kathryn Volk at the University of Arizona Lunar and Planetary Laboratory in 2019 about a constant source of new objects that may help explain the surprising rate of icy body impacts with Jupiter, such as the Shoemaker-Levy 9 event in 1994 when over twenty fragments of comet that collided with Jupiter were observed by astronomers at hundreds of observatories around the world.
Was Venus, described by Stephen Hawking as Earth’s “kissing cousin,” the solar system’s first habitable planet? Scientists have recently conjectured that Venus may have been radically different from the hellish Venus we see today, resembling Earth for its first three billion years, with vast oceans that could have been friendly to life. Fast forward to the 21st century –strange dark patches, enigmas, “unknown absorbers” have been detected floating inside the clouds of Venus capturing large amounts of solar radiation that may prove to be extraterrestrial microorganisms.
“Human blood is a testament to life’s origin in the ocean,” observed marine biologist Jacques Cousteau, “its chemical composition is nearly identical to that of sea-water.” New research funded by NASA appears to confirm Cousteau’s insight. Scientists have identified a process that might have been key in producing the first organic molecules on Earth about 4 billion years ago, before the origin of life. The process, which is similar to what might have occurred in some ancient underwater hydrothermal vents, may also have relevance to the search for life elsewhere in the universe. (more…)
Unlike our remarkably flat Solar System, with its planets all orbiting in the same plane, the alien star-system GW Orionis, located just 1,200 light-years away in the constellation of Orion, has three stars and a deformed, shattered and warped disc of tilted rings surrounding them. “Since more than half of stars in the sky are born with one or more companions, says astronomer Alexander Kreplin of the University of Exeter about pioneering new research that has revealed the first direct evidence that a three-star system can tear apart their planet-forming disc, “this raises an exciting prospect: there could be an unknown population of exoplanets that orbit their stars on very inclined and distant orbits.”
We are living through our Solar System’s twentieth, 223-250 million-year orbit of the Milky Way near the inner edge of the ephemeral spiral feature known as the Orion Arm or, less poetically, the Local Arm . The ghostly spiral arm is a concentrations of gas and dust where stars form, produced by disturbances within the Milky Way, or on occasions by a jolt from outside, such as a supernova. Life-threatening asteroids and comets are more frequent when a planetary system is crossing one of the galaxy’s spiral arms, where potentially deadly, dusty gas clouds congregate, stacking up in the equivalent of a hydrostatic jump.
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.
