Dark Matter: The Cosmos' Greatest Mystery Deepens. Like Hollywood legends Audrey Hepburn and Katharine Hepburn, dark energy and dark matter are completely unrelated, even though they share a name.
Dark energy, a force that makes the universe expand faster and faster all the time, is called dark because it's mysterious. Nobody knows what it is. Dark matter, on the other hand, a type of matter that outweighs ordinary stars and galaxies 5 to 1, is called dark because it's utterly invisible. We know it's there because its gravity yanks galaxies and stars around, but it neither emits nor reflects any light. Dark Matter & Dark Energy. Dark energy. Outer Space. Antimatter. In particle physics, antimatter is material composed of antiparticles, which have the same mass as particles of ordinary matter but opposite charges, as well as other particle properties such as lepton and baryon numbers and quantum spin.
Collisions between particles and antiparticles lead to the annihilation of both, giving rise to variable proportions of intense photons (gamma rays), neutrinos, and less massive particle–antiparticle pairs. The total consequence of annihilation is a release of energy available for work, proportional to the total matter and antimatter mass, in accord with the mass–energy equivalence equation, E = mc2. Antiparticles bind with each other to form antimatter, just as ordinary particles bind to form normal matter. Dark energy. Adding the cosmological constant to cosmology's standard FLRW metric leads to the Lambda-CDM model, which has been referred to as the "standard model" of cosmology because of its precise agreement with observations.
Dark energy has been used as a crucial ingredient in a recent attempt to formulate a cyclic model for the universe. Nature of dark energy Many things about the nature of dark energy remain matters of speculation. I wonder if this could be do. “Red Nugget” Galaxies Were Hiding in Plain Sight. In 2005 the Hubble Space Telescope spotted unusually small galaxies densely packed with red stars in the distant, young universe.
They were nicknamed “red nuggets,” not only because they are small and red but also their existence challenged current theories of galaxy formation, making them precious in astronomers’ eyes. Since no “red nuggets” were seen nearby, astronomers wondered why they had disappeared over time. New research shows that they didn’t disappear completely. “The View From Mars: Part One: ALMA (Atacama Large Millimetre Array)” by Jonathan de Villiers - NOWNESS. Astronomers Discover that the Milky Way Wobbles. Velocity map of the extended solar neighborhood as seen by RAVE.
Shown is a slice cut perpendicular to the plane of the Milky Way through the position of the Sun. Arrows indicate the streaming motions of the stars, the color indicates the velocity perpendicular to the plane of the Milky Way (Credit: AIP). Astronomers have discovered that Milky Way makes small wobbling or squishing movements, acting like a huge flag fluttering in the wind. 22 October 2013. Largest Spiral Galaxy in the Universe Confirmed. The spectacular barred spiral galaxy NGC 6872 has ranked among the biggest stellar systems for decades.
Now a team of astronomers from the United States, Chile and Brazil has crowned it the largest-known spiral, based on archival data from NASA's Galaxy Evolution Explorer (GALEX) mission, which has since been loaned to the California Institute of Technology, Pasadena, Calif. Measuring tip-to-tip across its two outsized spiral arms, NGC 6872 spans more than 522,000 light-years, making it more than five times the size of our Milky Way. BORG Survey Finds Oldest Known Galaxy Cluster in Universe. Galaxy clusters are the largest structures in the Universe, comprising hundreds to thousands of galaxies bound together by gravity.
This developing cluster, or protocluster, seen as it looked 13 billion years ago, presumably has grown into one of today's massive cities of galaxies, comparable to the nearby of more than 2000 galaxies. "These galaxies formed during the earliest stages of galaxy assembly, when galaxies had just started to cluster together," says the study's leader, Michele Trenti (University of Cambridge, UK and University of Colorado). "The result confirms our theoretical understanding of the buildup of galaxy clusters. And, Hubble is just powerful enough to find the first examples of them at this distance. " Remnant of a Dwarf Galaxy Devoured by the Milky Way. Astronomer Mary Williams, who is working with an international team in Germany on a million-star survey, found the "Aquarius Stream.
" "It was right on our doorstep, but we just couldn't see it. " Although models predicted that big galaxies such as the Milky Way were surrounded by dwarf galaxies, Prof Watson said astronomers rarely saw them. "Perhaps many of them have been eaten up by the big galaxies. Gigantic Disc of Dwarf Galaxies Discovered Orbiting Andromeda. A newly discovered form of circle dancing is perplexing astronomers; not due to its complex choreography, but because it's unclear why the dancers – dwarf galaxies – are dancing in a ring around the much larger Andromeda Galaxy.
The finding presents a challenge to our ideas of how all galaxies form and evolve. The surprising research result reveals that around half of Andromeda's 30-odd known dwarf galaxy satellites are orbiting the larger Andromeda Galaxy – the closest giant cosmic neighbor to our Milky Way. "When we looked at the dwarf galaxies surrounding Andromeda, we expected to find them buzzing around randomly, like angry bees around a hive. "Instead, we've found that half of Andromeda's satellites are orbiting together in an immense plane, which is more than a million light years in diameter but only 30 000 light years thick. Our Solar System Is Surrounded by Supernovae Debris. It took just five minutes for a NASA sounding rocket to confirm the decades-old theory that the solar system sits within a bubble of gas produced in 10 million-year-old supernovae explosions.
Background 0.25 keV X-ray radiation coming from all directions alerted astronomers to the possibility of a “Local Bubble” of hot gas in the late 1960s. Combined with evidence of local depletion of cool gasses, the idea was born that the hot gas was thrown off by a series of supernova explosions. However, the same radiation has also been explained as resulting from the exchange of charge between ions from the solar wind and neutral gases inside the solar system. Astronomers find the first sibling of the sun.
Sen—A team of researchers has identified for the first time a star directly related to the Sun, one almost certainly born from the same cloud of gas and dust. The find, led by astronomer Ivan Ramirez of The University of Texas, will help astronomers look for other solar siblings. It could lead to an understanding of how and where our Sun formed, and how our Solar System became hospitable for life. “We want to know where we were born,” Ramirez said. “If we can figure out in what part of the galaxy the Sun formed, we can constrain conditions on the early solar system. Galaxy. Astronomy.
Forced emergency landing on Mars Myth or Reality Documentary National Geographic 2016.