Astronomers have determined that our own Milky Way galaxy is part of a newly identified ginormous supercluster of galaxies, which they have dubbed "Laniakea," which means "immense heaven" in Hawaiian. This discovery clarifies the boundaries of our galactic neighborhood and establishes previously unrecognized linkages among various galaxy clusters in the local Universe.The Milky Way resides in the outskirts of the supercluster, whose extent has for the first time been carefully mapped using these new techniques. This so-called Laniakea Supercluster is 500 million light-years in diameter and contains the mass of one hundred million billion Suns spread across 100,000 galaxies.
Continue reading "Milky Way Found to Exist on Outskirts of a Vast Supercluster of 100,000 Galaxies" »
"Understanding Titan's hydrological cycle is one of the most important objectives of Cassini's extended mission," says ESA's Cassini-Huygens project scientist Nicolas Altobelli. "The changing seasons on Titan mean that soon we can again explore the lake-filled region at its north pole, and maybe spot seasonal phenomena we haven't seen before. This is crucial to getting a better understanding of what lies hidden beneath Titan's surface."
Continue reading "The Search is On for What Lies Hidden Beneath Titan's Surface" »
Lupus 4 is located about 400 light-years away from Earth, straddling the constellations of Lupus (The Wolf) and Norma (The Carpenter's Square). The cloud is one of several affiliated dark clouds found in a loose star cluster called the Scorpius–Centaurus OB association. The stars likely had a common origin in a gigantic cloud of material. The "OB" refers to the hot, bright, short-lived stars of spectral types O and B that are still shining brilliantly within the widely dispersed cluster as it travels through the Milky Way galaxy.
Continue reading "Milky Way's Gigantic Dark Clouds --Incubator of Stars" »
Massive stars end their life with a bang, exploding as supernovas and releasing massive amounts of energy and matter. What remains of the star is a small and extremely dense remnant: a neutron star or a black hole. Neutron stars come in several flavours, depending on properties such as their ages, the strength of the magnetic field concealed beneath their surface, or the presence of other stars nearby. Some of the energetic processes taking place around neutron stars can be explored with X-ray telescopes, like ESA's XMM-Newton.
Continue reading "Image of the Day: "The Blue Monster" --Rare Million-Year-Old Neutron Star Discovered Near a Recent Supernova" »
During an August 20 event at NASA headquarters, called Ancient Earth, Alien Earths, a panel of scientists from NASA and other organizations discussed how vastly different and inhospitable we all would find ancient Earth, if we could go back in time. Despite the conditions, though, it was an environment in which life began and evolved – and understanding how that was possible could help us recognize habitable planets around other stars.
Continue reading ""Ancient Earth, Alien Earths" --A NASA Panel Discussion (VIDEO)" »
Scientists continue to investigate the development of self-replicating, intricate sets of chemistry — in other words, life — from the chemical compounds thought available on early Earth. Out of this mixture of prebiotic chemicals, two nucleic acids — RNA and DNA — emerged as champions. Astrobiologists want to understand the origin of DNA and its genetic cousin, RNA, because figuring out how life got started here on Earth is key for gauging if it might ever develop on alien planets. New research intriguingly suggests that DNA, the genetic information carrier for humans and other complex life, might have had a rather humbler origin. In some microbes, a study shows, DNA pulls double duty as a storage site for phosphate. This all-important biomolecule contains phosphorus, a sometimes hard-to-get nutrient.
Continue reading "Origins of DNA --Shows How Life Could Have Evolved on Early Earth or Alien Planets" »
Only one species of the billions of species that have existed on Earth has shown an aptitude for radios and even we failed to build one during the first 99% of our 7 million year history. Charley Lineweaver, a provocative cosmologist with The Australian National University, believes the "Planet of the Apes Hypothesis" -a theory subscribed to by Carl Sagan and the astronomers involved with the Search for Extraterrestrial Intelligence (SETI), that human-like intelligence is a convergent feature of evolution -that there is an intelligence niche, into which other species will evolve if the human species goes extinct is based on a flawed notion of evolution, a notion that could have serious implications for our search for intelligent life elsewhere in the Milky Way Galaxy.
Continue reading ""The 'Intelligence Niche' is a Flawed Notion of Evolution" (Holiday Weekend Feature)" »
"Fundamentally, the solar system and everything in it was ultimately derived from a cloud of interstellar gas and dust," says Andrew Westphal, physicist at the University of California, Berkeley's Space Sciences Laboratory and lead author on the paper published this week in Science titled "Evidence for interstellar origin of seven dust particles collected by the Stardust spacecraft". "We're looking at material that's very similar to what made our solar system."
Continue reading "Stardust Mission Captures Origins of Our Solar System --"Clues to the Origin of Life Itself"" »
It may sound like science fiction, but astronomers have worked out a scheme that will allow them to detect and measure particles ten times smaller than the width of a human hair, even at many light-years distance. They can do this by observing a blue tint in the light from far-off objects caused by the way in which small particles, no more than a micron in size (one-thousandth of a millimeter) scatter light.
Continue reading ""Detecting Alien Planet Particles Smaller than a Human Hair" --New SETI Breakthrough" »
Astrophysicists obtained for the first time spectra of radiating cobalt registered at the supernova SN2014J, shown above, located 11 million light-years from Earth. Isotope 56Co has a half-life of just 77 days, and does not exist in normal conditions. However, during a giant thermonuclear explosion of a supernova, this short-lived radioactive isotope is produced in large quantities. The reason was the rarity of explosions at such a distance – 11 million light-years is a large value on the galactic scale (the diameter of a galaxy is about 100,000 light-years, the distance between stars is a few light-years), but on an intergalactic scale it is a relatively short distance. There are several hundreds of galaxies within a radius of ten million light-years; supernovae produce explosions like this (type Ia explosions) once every few centuries in a galaxy, including a type Ia supernova that exploded in the Milky Way in 1606.
Continue reading "Supernova's Giant Thermonuclear Explosion Reveals Rare Isotope" »