In July of 2012, astronomers observed a spiral galaxy in the early universe, billions of years before many other spiral galaxies formed while using the Hubble Space Telescope. They were taking pictures of about 300 very distant galaxies in the early universe to study their properties. This distant object existed roughly three billion years after the Big Bang, and light from this part of the universe has been traveling to Earth for about 10.7 billion years.
“The fact that this galaxy exists is astounding,” said David Law, lead author of the study a fellow at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics. “Current wisdom holds that such ‘grand-design’ spiral galaxies simply didn’t exist at such an early time in the history of the universe.” A ‘grand design’ galaxy has prominent, well-formed spiral arms.
“As you go back in time to the early universe, galaxies look really strange, clumpy and irregular, not symmetric,” said Alice Shapley, a UCLA associate professor of physics and astronomy, and co-author of the study. “The vast majority of old galaxies look like train wrecks. Our first thought was, why is this one so different, and so beautiful?”
via Did Astronomers Find the Oldest Spiral Galaxy in the Cosmos?.
The image above from the Hubble Space Telescope CANDELS survey, highlights the most distant galaxy in the universe with a measured distance, dubbed z8_GND_5296. The most distant spectroscopically confirmed galaxy ever found — one created at about 700 million years after the Big Bang — has been detected by astronomers at Texas A&M University and the University of Texas at Austin.
The researchers suspect they may have zeroed in on the era when the universe made its transition from an opaque state in which most of the hydrogen is neutral to a translucent state in which most of the hydrogen is ionized. So it’s not necessarily that the distant galaxies aren’t there. It could be that they’re hidden from detection behind a wall of neutral hydrogen fog, which blocks the hydrogen emission signal.
The astronomers note that this is one of two major changes in the fundamental essence of the universe since its beginning — the other being a transition from a plasma state to a neutral state. He is leading the effort on a follow-up paper that will use a sophisticated statistical analysis to explore that transition further.
“Everything seems to have changed since then,” said Vithal Tilvi, a Texas A&M postdoctoral research associate and co-author of the paper now available online.“If it was neutral everywhere today, the night sky that we see wouldn’t be as beautiful. What I’m working on is studying exactly why and exactly where this happened. Was this transition sudden, or was it gradual?”
Our home galaxy, the Milky Way, creates about one or two Sun-like stars every year or so. But this newly discovered galaxy forms around 300 a year. It was observed by the researchers as it was 13 billion years ago. Because the universe has been expanding the whole time, the researchers estimate the galaxy’s present distance to be roughly 30 billion light years away. The detected emission line at a wavelength of 1.0343 micrometres is likely to be Lyman α emission, placing this galaxy at a redshift z = 7.51, an epoch 700 million years after the Big Bang.
via The Most Distant Galaxy in the Observable Universe Discovered –30 Billion Light Years from the Milky Way!.
Is our universe merely one of billions? Evidence of the existence of multiverse revealed for the first time by a cosmic map of background radiation data gathered by Planck telescope. The first hard evidence that other universes exist has been claimed to have been found by cosmologists studying new Planck data released this past June. They have concluded that it shows anomalies that can only have been caused by the gravitational pull of other universes.\”Such ideas may sound wacky now, just like the Big Bang theory did three generations ago,\” says George Efstathiou, professor of astrophysics at Cambridge University.\”But then we got evidence and now it has changed the whole way we think about the universe.\”Scientists had predicted that it should be evenly distributed, but the map shows a stronger concentration in the south half of the sky and a cold spot that cannot be explained by current understanding of physics. Laura Mersini-Houghton, theoretical physicist at the University of North Carolina at Chapel Hill, and Richard Holman, professor at Carnegie Mellon University, predicted that anomalies in radiation existed and were caused by the pull from other universes in 2005. Mersini-Houghton will be in Britain soon promoting this theory and, we expect, the hard evidence at the Hay Festival on May 31 and at Oxford on June 11.
via “Other Universes are Pulling on Our Universe” — New Planck Data Triggers Controversy Todays Most Popular.
In February 2012, NASAs Interstellar Boundary Explorer, the centerpiece of a $169 million mission mapping the frontier of the suns influence, detected atoms from interstellar space streaming by Earth, that are different from the chemical make-up of the solar system.”Our solar system is different than the space right outside it, suggesting two possibilities,” said David McComas, IBEX principal investigator, at the Southwest Research Institute in San Antonio. “Either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside, or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space.””Weve directly measured four separate types of atoms from interstellar space and the composition just doesnt match up with what we see in the solar system,” said Eric Christian, IBEX mission scientist at NASAs Goddard Space Flight Center in Greenbelt, Md. “IBEXs observations shed a whole new light on the mysterious zone where the solar system ends and interstellar space begins.”
via “Did Our Solar System Evolve in a More Oxygen-Rich Region of the Milky Way?” Space-Mission Findings Baffle Scientists.
“Each bright city light is a galaxy, and the dark areas between the lights that appear to be empty during the night are actually full of dark matter. You can think of the dark matter in a galaxy cluster as being the infrastructure within which the galaxies live,” say an international team of astronomers from Taiwan, UK, Japan, and the Academia Sinica Institute of Astronomy and Astrophysics ASIAA. The researchers used a large sample of galaxy clusters to find out how the density of dark matter changes from the center of a typical galaxy cluster to its outskirts.has used the Subaru Telescope to measure the density of dark matter in fifty galaxy clusters and found that its density gradually decreases from the center of these cosmic giants to their diffuse outskirts. This new evidence about the mysterious dark matter that pervades our Universe conforms to the predictions of cold dark matter theory, known as “CDM”.Almost all of the bright objects in the Hubble Space Telescope image above are galaxies in the cluster known as Abell 2218. The cluster is so massive and so compact that its gravity bends and focuses the light from galaxies that lie behind it. As a result, multiple images of these background galaxies are distorted into long faint arcs – a simple lensing effect analogous to viewing distant street lamps through a glass of wine. The cluster of galaxies Abell 2218 is itself about two billion light-years away in the northern constellation Draco. Three images of this young, still-maturing galaxy are faintly visible in the white contours near the image top and the lower right. The recorded light, further analyzed with a Keck Telescope, left this galaxy when the universe was only about five percent of its current age.
via Galaxy Clusters Reveal Distribution of Dark Matter.
A Swiss team from the famous Geneva Observatory has achieved extraordinary precision using a comparatively small 1.2-metre telescope for an observing programme stretching over many years. They have discovered a new class of variable stars by measuring minute variations in stellar brightness in the open star cluster NGC 3766 in the constellation of Centaurus (The Centaur), and is estimated to be about 20 million years old.
via New Unknown Type of Star Discovered.
A neutron star resembles a giant atomic nucleus, with 1–2 times the Sun’s mass packed into a ball about 20 kilometres across. Its gravity is so strong that a projectile would need to be launched at about half the speed of light to escape from its surface. Extreme density, pressure, temperature, magnetism and relativistic gravity make these objects fascinating but challenging to study. Surprising observations of spin-down irregularities in one intensely magnetized neutron star, reported by Archibald et al.1 on page 591 of this issue, offer clues about exotic processes occurring deep inside these objects.
The basic structure of a neutron star is generally agreed on. It has a crust about 1 km thick, in which nuclei are arranged in a crystal lattice immersed in a ‘sea’ of electrons. Near the surface, the nuclei are plain iron, but the pressure and density increase rapidly with depth, so that the nuclei become increasingly bloated and neutron-rich. At moderate depth, neutrons ‘drip’ out of the nuclei, forming a neutral liquid between the lattice nuclei. At the base of the crust, the bloated nuclei merge. Below this lies pure nuclear fluid, more than 200 trillion times denser than liquid water.
via Astrophysics: A glimpse inside a magnetar : Nature : Nature Publishing Group.
For one sleepless week in early September 2009, Garth Illingworth and his team had the early Universe all to themselves. At NASA’s request, Illingworth, Rychard Bouwens and Pascal Oesch had just spent the previous week staring into their computer screens at the University of California, Santa Cruz, scanning through hundreds of black-and-white portraits of faint galaxies recorded in a multi-day time exposure by a newly installed infrared camera on the Hubble Space Telescope. NASA simply wanted the three astronomers to preview the images and make sure that the camera was working correctly, before the agency released the data more widely.
via Galaxy formation: Cosmic dawn : Nature News & Comment.
The Hubble Space Telescope image below centers on the 100-million-solar-mass black hole at the hub of the neighboring spiral galaxy M31, or the Andromeda galaxy, the only galaxy outside the Milky Way visible to the naked eye and the only other giant galaxy in the local group. This is the sharpest visible-light image ever made of the nucleus of an external galaxy. The event horizon, the closest region around the black hole where light can still escape, is too small to be seen, but it lies near the middle of a compact cluster of blue stars at the center of the image.
The compact cluster of blue stars is surrounded by the larger “double nucleus” of M31, discovered with the Hubble Space Telescope in 1992. The double nucleus is actually an elliptical ring of old reddish stars in orbit around the black hole but more distant than the blue stars. When the stars are at the farthest point in their orbit they move slower, like cars on a crowded freeway. This gives the illusion of a second nucleus.
The blue stars surrounding the black hole are no more than 200 million years old, and therefore must have formed near the black hole in an abrupt burst of star formation. Massive blue stars are so short-lived that they would not have enough time to migrate to the black hole if they were formed elsewhere.
Astronomers are trying to understand how apparently young stars were formed so deep inside the black hole’s gravitational grip and how they survive in an extreme environment.
via The Weekend Image : Andromeda Galaxy’s Supermassive Black Hole.
The black hole at the center of the super giant elliptical galaxy M87 in cluster Virgo fifty million light-years away is the most massive black hole for which a precise mass has been measured -6.6 billion solar masses. Orbiting the galaxy is an abnormally large population of about 12,000 globular clusters, compared to 150-200 globular clusters orbiting the Milky Way. The team theorized that the M87 black hole grew to its massive size by merging with several other black holes. M87 is the largest, most massive galaxy in the nearby universe, and is thought to have been formed by the merging of 100 or so smaller galaxies. The M87 black hole’s large size and relative proximity, astronomers think that it could be the first black hole that they could actually “see.”
In 2011, using the Frederick C. Gillett Gemini Telescope on Mauna Kea, Hawaii, a team of astronomers calculated the black hole’s mass, which is vastly larger than the black hole in the center of the Milky Way, which is about 4 million solar masses. The black hole’s event horizon, 20 billion km across “could swallow our solar system whole.”
via Giant Elliptical Galaxy Harbors Largest Known Black Hole in Universe.