“Finding temperatures near these three inactive fractures that are unexpectedly higher than those outside them adds to the intrigue of Enceladus,” said Cassini Project Scientist Linda Spilker at NASA’s Jet Propulsion Laboratory, Pasadena, California. “What is the warm underground ocean really like and could life have evolved there? These questions remain to be answered by future missions to this ocean world.”
"This white dwarf is so close to the black hole that material is being pulled away from the star and dumped onto a disk of matter around the black hole before falling in," said Arash Bahramian, with the University of Alberta (Canada) and Michigan State University. "Luckily for this star, we don't think it will follow this path into oblivion, but instead will stay in orbit."
The appearance of supermassive black holes at the dawn of the universe has puzzled astronomers since their discovery more than a decade ago. A supermassive black hole is thought to form over billions of years, but more than two dozen of these behemoths have been sighted within 800 million years of the Big Bang 13.8 billion years ago.
From the journey of protons racing through the world's largest particle collider in Europe to up-close views of the Big Bang and emergent universe, and the nearly mile-deep descent to an underground experiment in South Dakota, sceintist around the world are in hot pursuit of dark matter --what some physicists are callling the "operating system" of the universe.
Our current cosmological standard model assumes that general relativity and the standard model of particle physics have been a good description of the basic physics of the universe throughout its history. It assumes that the large-scale geometry of the universe is flat: The total energy of the universe is zero. This implies that Euclidean geometry, the mathematics taught to most of us in middle school, is valid on the scale of the universe. Although the geometry of the universe is simple, its composition is strange: The universe is composed not just of atoms (mostly hydrogen and helium), but also dark matter and dark energy.
Dark matter, which we have so far detected only through its gravitational effects though it makes up an estimated 85 percent of the total mass of the universe -- is invisible and we don't yet know what it's made of. Researchers are scanning the night sky and designing ultrasensitive underground particle detectors in hopes of solving its mysteries.
Although general relativity is now a hundred-year-old theory, it remains a powerful, and controversial, idea in cosmology. It is one of the basic assumptions behind our current cosmological model: a model that is both very successful in matching observations, but implies the existence of both dark matter and dark energy. These signify that our understanding of physics is incomplete. We will likely need a new idea as profound as general relativity to explain these mysteries and require more powerful observations and experiments to light the path toward our new insights.
Image at the top of the page is a computerized rendering showing the distribution of dark matter as two galaxies collide. Credit: "Phantom of the Universe"
NASA's upcoming mission to investigate the habitability of Jupiter's icy moon Europa defy's Arthur C. Clark's admonition: "Attempt no landing there!" The bold venture now has a formal name: Europa Clipper, which harkens back to the clipper ships that sailed across the oceans of Earth in the 19th century. Clipper ships were streamlined, three-masted sailing vessels renowned for their grace and swiftness. These ships rapidly shuttled tea and other goods back and forth across the Atlantic Ocean and around the globe.
In January of 2015, astronomers discovered a solar system with five Earth-sized planets dating back to the dawn of the Galaxy. "There are far-reaching implications for this discovery," said Tiago Campante, from the University of Birmingham's School of Physics and Astronomy, who led the research. "We now know that Earth-sized planets have formed throughout most of the Universe's 13.8 billion year history, which could provide scope for the existence of ancient life in the Galaxy. By the time the Earth formed, the planets in this system were already older than our planet is today. This discovery may now help to pinpoint the beginning of what we might call the "era of planet formation."
Quasars, stupendously bright regions in the cores of galaxies, powered by gargantuan black holes, will deepen our understanding of why nearly all galaxies have supermassive black holes at their cores, begging the chicken-or-the-egg question of which came first, the galaxies themselves or the black holes, or whether the two arose interrelatedly.
On Feb. 22, astronomers announced that the ultra-cool dwarf star, TRAPPIST-1, hosts a total of seven Earth-size planets that are likely rocky, a discovery made by NASA's Spitzer Space Telescope in combination with ground-based telescopes. NASA's planet-hunting Kepler space telescope also has been observing this star since December 2016. Today these additional data about TRAPPIST-1 from Kepler are available to the scientific community.
"Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven't identified a possible natural source with any confidence," said theorist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. "An artificial origin is worth contemplating and checking."
Chinese astronomers have renewed their ambitious attempt to build two powerful telescopes at Dome A, the highest place in Antarctica. Professor Cui, Deputy Director of the Chinese Center for Antarctic Astronomy, said the two major telescopes would greatly assist the research of black holes and dark energy, as well as the origins of life and the universe, reported Xinhua News Agency.