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What is the Universe Expanding Into?‬‏

What is the Universe Expanding Into?‬‏
Related:  Cosmic mapping

First Planck results: the Universe is still weird and interesting Our current model of cosmology—the origin and structure of the whole Universe—has survived another major test, with the release of the first 15 months of data from the Planck mission. Planck is a European Space Agency mission, designed to study the cosmic microwave background (CMB), which preserves information about the conditions that persisted immediately after the Big Bang. Combined with results from prior experiments, Planck has revealed a Universe a little older than previously thought, and with a slightly different balance of ingredients. Although there were no major surprises, some of its data provided stronger hints about inflation, a popular model that explains why the modern Universe looks the way it does. Other measurements ruled out extra neutrinos, provided even stronger evidence for the existence (though not the identity) of dark matter, and indicated that there's a bit less dark energy than previous measurements had suggested. That image helps tell us the Universe's age.

Universal Formula for Cosmic Voids +Enlarge image N. Hamaus/Paris Inst. of Astrophys. & M. Most of the matter in the Universe consists of the mysterious dark matter, and cosmologists would like to better understand how it is organized in space. Scarcely anything is known about dark matter except that, apart from its gravitational effects, it hardly interacts with ordinary matter or light. Earlier simulations have shown that a uniform dark matter “gas” collapses under its own gravity into a tangled web of sheets and filaments that is permeated by relatively empty voids [1, 2]. Nico Hamaus of the Paris Institute of Astrophysics and his co-workers have now carried out simulations that probe the density profiles of dark matter voids in more detail than previous studies. Just as in previous studies, the dark matter clustered and created voids having a wide range of shapes and sizes. What’s more, the team found that the profile could be fitted empirically with a rather simple formula that contains just two parameters. J.

Better Not Avoid A Cosmic Void (Inside Science) -- Sometimes nothingness can reveal a whole lot. While the universe is mostly empty, it contains bubble-like voids that are even emptier, taking up most of the space in the cosmos. And new research shows that these voids all look similar regardless of size — a consistency that may help unravel some of the universe's biggest mysteries. If you zoom way out, all the matter in the universe looks like a huge cobweb, consisting of an expansive network of filaments and wall-like structures that crisscross one another. More than 80 percent of this matter is dark matter, the invisible and mysterious stuff that appears to interact only gravitationally with the regular matter that makes up stars and galaxies. But between the filaments and walls of this cosmic web are vast cosmic voids. "Normally people look for the presence of something — and that's very important," said Joseph Silk of the Paris Institute of Astrophysics. "That's the hope," Hamaus said.

3D Galactic Map May Solve Interstellar Puzzle Scientists have created the first 3D map of a type of astronomical interference that has puzzled astronomers for nearly a century. The new map could help scientists finally nail down the identity of the material that creates "diffuse interstellar bands" (DIBs) in observations of stars, the study authors said. The researchers focused on the single DIB 8620, one of over 400 absorption lines, with the goal of narrowing down its source. [Top 10 Star Mysteries] "DIB 8620 does not seem special compared to other DIBs," lead author Janez Kos, of the University of Ljubljana in Slovenia, told by email. However, as a spectral feature often used to measure stellar motion, it is "the most observed DIB." The result was the first large-scale map of DIB interference, and the first three-dimensional study of the DIB-bearing clouds in the interstellar medium. Some of the first proposed sources were molecules on dust grainsbetween stars, according to Kos.

From Quark to Quasar: The Observable Universe “That tiny dot that you can hardly make out in the screen is the Virgo Supercluster, where our galaxy, our local group and several others reside. All of those other dots are superclusters, each containing perhaps trillions of stars. Via WikiMedia If you really want a headache (the good kind), take a long look at this “photo”. You and I, and all the things we’ve ever known, are smack in the middle of this image, along with our Local group (which is a part of the larger Virgo Supercluster). Since the speed of light is a constant in the vacuum of space, from our location on Earth, there is an outer edge to what is we can see in the cosmos. It seems confusing, but there is a simple explanation: the universe has expanded in all directions since the big bang. This diagram shows how Earth’s observable universe compares to other places in space (Image via Nina) The “observable” universe is thought to consist of roughly: -*10 million superclusters - *25 billion galaxy groups The bombshell?

Cosmic Spider Swallows Starlight in Amazing Telescope View (Video, Photos) A dark, spider-shaped cloud of cosmic gas blocks out light from stars in a new image taken by a telescope in the Southern Hemisphere. The amazing photo, taken by a telescope at the European Southern Observatory's La Silla Observatory in Chile, is filled with stars glowing brightly in a variety of colors. Red, blue, yellow and orange stars frame the gas blob called Lupus 4, which blots out light from other, more distant stars in the center of the image. Fly through the image in a new video of the Lupus 4 space cloud from ESO. Eventually, Lupus 4, which is located about 400 light-years from Earth, could give birth to its own stars. [Star Quiz: Test Your Stellar Smarts] A dark cloud of gas called Lupus 4 blocks out more-distant stars. "How many stars might eventually start to shine within Lupus 4? Another gas cloud in the same area, called Lupus 3, already hosts about 40 young stars that formed over the course of the last 3 million years, ESO said.

Welcome To Our New Galactic Supercluster Home: Laniakea | The Skeptics Guide to the Universe Your ultimate address just changed. Astronomers have discovered that the supercluster we’ve long-believed our Milky Galaxy resides in is actually just an appendage on the outskirts of an even more giant new supercluster called Laniakea. Every now and then we receive an email from someone who lists their address in a much more complete way than most everyone else does. Instead of listing something like a town/state/country, they take a humorous much broader perspective that would seemingly be of interest only to an alien from the other side of the visible universe. They usually take the form of: Earth/Milky Way/Local Group/Virgo-Cluster/Virgo-SuperCluster/Visible Universe. We now know that this is wrong (and perhaps why inter-galactic email is so slow) The organization of matter in the visible universe can be thought of as a hierarchy of groupings of stars. Galaxy Groups: Small collections (less than 50) of gravitationally bound galaxies. Even Bigger? Welcome to your new home. Press Release

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