Have a discussion about the origins of the Universe and, ere long, someone will inevitably use the term “the Big Bang” to describe the initial moment of expansion of everything that was to everything that is. But in reality “Big Bang” isn’t a very good term since “big” implies size (and when it occurred space didn’t technically exist yet) and there was no “bang.” In fact the name wasn’t ever even meant to be an official moniker, but once it was used (somewhat derisively) by British astronomer Sir Fred Hoyle in a radio broadcast in 1949, it stuck.
Unfortunately it’s just so darn catchy.
This excellent video from minutephysics goes a bit more into depth as to why the name is inaccurate — even though we’ll likely continue using it for quite some time. (Thanks to Sir Hoyle.)
And you have to admit, a television show called “The Everywhere Stretch Theory” would never have caught on. Bazinga!
It’s a new Symphony of Science video from melodysheep (aka John D. Boswell). It features Neil deGrasse Tyson, Lawrence Krauss, Michio Kaku, and Morgan Freeman. It’s about black holes.
The FastSound project's 3D map of the large-scale structure of a region in the Universe about 4.7 billion years after the Big Bang. This area covers 2.5 times 3 degrees of the sky, with a radial distance spanning 12-14.5 billion light years in comoving distance or 8-9.6 billion light years in light travel distance. Credit: NAOJ, SDSS, CFHT.
I remember seeing the Hubble 3-D IMAX movie in 2010 and literally gasping when the view pulled back from zooming into distant stars and galaxies to show clusters and superclusters of galaxies interwoven like a web, creating the large scale structure of the Universe. In 3-D, the structure looks much like the DNA double helix or a backbone.
Now, a new project that aims to map the Universe’s structure has looked back in time to create a 3-D map showing a portion of the Universe as it looked nine billion years ago. It shows numerous galaxies and interestingly, already-developed large-scale structure of filaments and voids made from galaxy groups.
The map was created by the FastSound project, which is surveying galaxies in the Universe using the Subaru Telescope’s new Fiber Multi-Object Spectrograph (FMOS). The team doing the work is from Kyoto University, the University of Tokyo and the University of Oxford.
The team said that although they can see that the clustering of galaxies is not as strong back when the Universe was 4.7 billion years old as it is in the present-day Universe, gravitational interaction will eventually result in clustering that grows to the current level.
The new map spans 600 million light years along the angular direction and two billion light years in the radial direction. The team will eventually survey a region totaling about 30 square degrees in the sky and then measure precise distances to about 5,000 galaxies that are more than ten billion light years away.
But the FastSound project hopes to create a 3-D map of the very distant Universe by covering the volume of the Universe farther than ten billion light years away. FMOS is a wide-field spectroscopy system that enables near-infrared spectroscopy of over 100 objects at a time, with an exceptionally wide field of view when combined with the light collecting power of the 8.2 meter primary mirror of the telescope.
The map released today is just the first from FastSound. The final 3-D map of the distant Universe will precisely measure the motion of galaxies and then measure the rate of growth of the large-scale structure as a test of Einstein’s general theory of relativity.
Although scientists know that the expansion of the Universe is accelerating, they do not know why – whether it is from dark energy or whether gravity on cosmological scales may differ from that of general relativity, this mystery is one of the biggest questions in contemporary physics and astronomy. A comparison of the 3D map of the young Universe with the predictions of general relativity could eventually reveal the mechanism for the mysterious acceleration of the Universe.
The team said their 3-D map shown in this release uses a measure of “comoving” distance rather than light travel distance. They explained:
Light travel distance refers to the time that has elapsed from the epoch of the observed distant galaxy to the present, multiplied by the speed of light. Since the speed of light is always constant for any observer, it describes the distance of the path that a photon has traveled. However, the expansion of the Universe increases the length of the path that the photon traveled in the past. Comoving distance, the geometrical distance in the current Universe, takes this effect into account. Therefore, comoving distance is always larger than the corresponding light travel distance.
In the lead image above from FastSound, the colors of the galaxies indicate their star formation rate, i.e., the total mass of stars produced in a galaxy every year. The gradation in background color represents the number density of galaxies; the underlying mass distribution (which is dominated by invisible dark matter that accounts for about 30% of the total energy in the Universe) and how it would look like this if we could see it. The lower part of the figure shows the relative locations of the FastSound and the Sloan Digital Sky Survey (SDSS) regions, indicating that the FastSound project is mapping a more distant Universe than SDSS’s 3D map of the nearby Universe.
Collisions of neutron stars produce powerful gamma-ray bursts – and heavy elements like gold (Credit: Dana Berry, SkyWorks Digital, Inc.)
Are you wearing a gold ring? Or perhaps gold-plated earrings? Maybe you have some gold fillings in your teeth… for that matter, the human body itself naturally contains gold — 0.000014%, to be exact! But regardless of where and how much of the precious yellow metal you may have with you at this very moment, it all ultimately came from the same place.
And no, I don’t mean Fort Knox, the jewelry store, or even under the ground — all the gold on Earth likely originated from violent collisions between neutron stars, billions of years in the past.
Recent research by scientists at the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Massachusetts has revealed that considerable amounts of gold — along with other heavy elements — are produced during impacts between neutron stars, the super-dense remains of stars originally 1.4 to 9 times the mass of our Sun.
The team’s investigation of a short-duration gamma-ray outburst that occurred in June (GRB 130603B) showed a surprising residual near-infrared glow, possibly from a cloud of material created during the stellar merger. This cloud is thought to contain a considerable amount of freshly-minted heavy elements, including gold.
“We estimate that the amount of gold produced and ejected during the merger of the two neutron stars may be as large as 10 moon masses – quite a lot of bling!” said lead author Edo Berger.
“With this remnant of a dead neutron star, I thee wed.” (FreeDigitalPhotos.net/bigjom)
The mass of the Moon is 7.347 x 1022 kg… about 1.2% the mass of Earth. The collision between these neutron stars then, 3.9 billion light-years away, produced 10 times that much gold based on the team’s estimates.
Quite a lot of bling, indeed.
Gamma-ray bursts come in two varieties – long and short – depending on the duration of the gamma-ray flash. GRB 130603B, detected by NASA’s Swift satellite on June 3rd, lasted for less than two-tenths of a second.
Although the gamma rays disappeared quickly, GRB 130603B also displayed a slowly fading glow dominated by infrared light. Its brightness and behavior didn’t match the typical “afterglow” created when a high-speed jet of particles slams into the surrounding environment.
Instead, the glow behaved like it came from exotic radioactive elements. The neutron-rich material ejected by colliding neutron stars can generate such elements, which then undergo radioactive decay, emitting a glow that’s dominated by infrared light – exactly what the team observed.
“We’ve been looking for a ‘smoking gun’ to link a short gamma-ray burst with a neutron star collision,” said Wen-fai Fong, a graduate student at CfA and a co-author of the paper. “The radioactive glow from GRB 130603B may be that smoking gun.”
The team calculates that about one-hundredth of a solar mass of material was ejected by the gamma-ray burst, some of which was gold. By combining the estimated gold produced by a single short GRB with the number of such explosions that have likely occurred over the entire age of the Universe, all the gold in the cosmos – and thus on Earth – may very well have come from such gamma-ray bursts.
Watch an animation of two colliding neutron stars along with the resulting GRB below (Credit: Dana Berry, SkyWorks Digital, Inc.):
How much gold is there on Earth, by the way? Since most of it lies deep inside Earth’s core and is thus unreachable, the total amount ever retrieved by humans over the course of history is surprisingly small: about 172,000 tonnes, or enough to make a cube 20.7 meters (68 feet) per side (based on the Thomson Reuters GFMS annual survey.) Some other estimates put this amount at slightly more or less, but the bottom line is that there really isn’t all that much gold available in Earth’s crust… which is partly what makes it (and other “precious” metals) so valuable.
And perhaps the knowledge that every single ounce of that gold was created by dead stars smashing together billions of years ago in some distant part of the Universe would add to that value.
“To paraphrase Carl Sagan, we are all star stuff, and our jewelry is colliding-star stuff,” Berger said.
The team’s findings were presented today in a press conference at the CfA in Cambridge. (See the paper here.)
Think about Dr. Seuss’ classic book If I Ran The Zoo. Young Gerald McGrew has an active imagination creating heretofore unheard of creatures to make his zoo the most astounding by far. All of Gerald’s inventions are quite interesting. But add them to the long list of different beings humans across time have dreamt up – from the Sphinx to the Griffin – and they still pale in comparison to actual creatures in existence. And yet, says author David Toomey in his new book Weird Life: The Search for Life That is Very, Very Different from Our Own, there are likely countless undiscovered forms of very weird life that we can’t even begin to imagine.
The very definition of weird involves words such as strikingly odd, strange, and bizarre. David Toomey travels down the strange path of Weird Life starting at the striking discoveries of extremophiles. Extremophile organisms push the boundaries of what conditions we thought life could exist in, thriving in environments too extreme for humans.
Astrobiologists soak up extremophiles because similar environmental conditions in our solar system might correlate with similar extreme life elsewhere. Would life elsewhere look exactly like our cold or acid-loving extremophiles on Earth or would they be even weirder? Vast lakes of liquid methane exist on Saturn’s moon, Titan. Can we find evidence of microscopic life in such an environment? We need to know how to isolate it, what exactly to test for and finance a mission to explore it. The fun part is that Titan is among a handful of strange places we theorize may harbor life in our own solar system. Recent discoveries of planets in other star systems are fodder for speculation of life, familiar to us or what we would deem as weird life.
My family and I recently visited Roswell, New Mexico. The entire town markets itself on the human notion that life exists elsewhere in a varied form from what we see in the mirror every day. Chapter Seven in Toomey’s book discusses “Intelligent Weird Life”. While some scientists having the thrilling job of searching for signs of intelligent life in the universe, some scientists enjoy the search for life on a much smaller scale on Earth – from the ocean’s bottom to the clouds above. Extremophiles push the boundaries of our beliefs and expectations. We are constantly made aware of what little we actually know. It’s possible a strange brew of exotic life exists here on Earth; we’re just not able to detect it, yet.
If phrases like “shadow biosphere”, “silicon life,” “desert varnish,” and “cloud borne Venusians” don’t pique your interest then perhaps this isn’t the book for you. For those interested in life very, very different from our own, this is right up your alley. Chapters entitled “A Bestiary of Weird Life” and “Weird Life in the Multiverse” certainly made this reviewer turn the pages of Weird Life with a childlike glee. Without a doubt, David Toomey’s book will teach you something you don’t know. Information interspersed with humor, appropriate science bios and anecdotes makes this a well rounded book for your bedside reading.
The international Super Cryogenic Dark Matter Search (SuperCDMS) has detected what may be the particle that's thought to make up dark matter throughout the Universe.
Dark matter: it’s invisible, it’s elusive, it’s controversial… and it’s everywhere — in the Universe, yes, but especially in the world of astrophysics, where researchers have been exhaustively trying to reveal its true identity for decades.
Now, scientists with the international Super Cryogenic Dark Matter Search (SuperCDMS) experiment are reporting the detection of a particle that’s thought to make up dark matter: a weakly-interacting massive particle, or WIMP. According to a press release from Texas A&M University (whose high-energy physicist Rupak Mahapatra is a principal investigator in the experiment) SuperCDMS has identified a WIMP-like signal at the 3-sigma level, which indicates a 99.8 percent chance of an actual discovery — a “concrete hint,” as it’s being called.
“In high-energy physics, a discovery is only claimed at 5-sigma or better,” Mahapatra said. “So this is certainly very exciting, but not fully convincing by the standards. We just need more data to be sure. For now, we have to live with this tantalizing hint of one of the biggest puzzles of our time.”
If this is indeed a WIMP it will be the first time such a particle has been directly observed, lending more insight into what dark matter is… or isn’t.
Notoriously elusive, WIMPs rarely interact with normal matter and therefore are difficult to detect. Scientists believe they occasionally bounce off, or scatter like billiard balls from, atomic nuclei, leaving behind a small amount of energy capable of being tracked by detectors deep underground, particle colliders such as the Large Hadron Collider at CERN and even instruments in space like the Alpha Magnetic Spectrometer (AMS) mounted on the International Space Station.
A stack of crystal germanium CDMS detectors (Fermilab)
The CDMS experiment, located a half-mile underground at the Soudan mine in northern Minnesota and managed by the United States Department of Energy’s Fermi National Accelerator Laboratory, has been searching for dark matter since 2003. The experiment uses very sophisticated detector technology and advanced analysis techniques to enable cryogenically cooled (almost absolute zero temperature at -460 degrees F) germanium and silicon targets to search for the rare recoil of dark matter particles.
This newly-announced detection actually comes from data acquired during an earlier phase of the experiment.
“This result is from data taken a few years ago using silicon detectors manufactured at Stanford that are now defunct,” Mahapatra said. “Increased interest in the low mass WIMP region motivated us to complete the analysis of the silicon-detector exposure, which is less sensitive than germanium for WIMP masses above 15 giga-electronvolts [one GeVa is equal to a billion electron volts] but more sensitive for lower masses. The analysis resulted in three events, and the estimated background is 0.7 events.”
Although Mahapatra says the result is certainly encouraging and worthy of further investigation, he cautions it should not be considered a discovery just yet.
“We are only 99.8 percent sure, and we want to be 99.9999 percent sure,” Mahapatra said. “At 3-sigma, you have a hint of something. At 4-sigma, you have evidence. At 5-sigma, you have a discovery.”
“In medicine, you can say you are curing 99.8 percent of the cases, and that’s OK. When you say you’ve made a fundamental discovery in high-energy physics, you can’t be wrong.”
– Dr. Rupak Mahapatra, SuperCDMS principal investigator, Texas A&M University
Advanced 6-inch silicon detectors developed by Mahapatra’s lab at Texas A&M
The collaboration will continue to probe this WIMP sector using the SuperCDMS Soudan experiment’s operating germanium detectors and is considering using larger, more advanced 6-inch silicon detectors developed at the Texas A&M’s Department of Electrical Engineering in future experiments.
The team has detailed its results in a paper published in arXiv that eventually will appear in Physical Review Letters. Mahapatra will also announce the results today at 12 p.m. CDT in a talk at the Mitchell Institute for Fundamental Physics and Astronomy.
The Big Bang Theory: A history of the Universe starting from a singularity and expanding ever since. Credit: grandunificationtheory.com
One of the greatest mysteries is how the Universe began — and also how and why does it appear to be ever-expanding? CERN physicist Tom Whyntie shows how cosmologists and particle physicists are exploring these questions by replicating the heat, energy, and activity of the first few seconds of our Universe, from right after the Big Bang.
Want to learn more about our Universe or refresh your astronomical knowledge? Cosmoquest has two new online astronomy classes, and they are a great opportunity expand your horizons! The two classes are “The Sun and Stellar Evolution” (April 15 – May 8, 2013) and “Introduction to Cosmology” (April 23 – May 16, 2013) Cosmoquest offers the convenience of an online class along with live (and lively!) interaction with your instructor and a small group astronomy enthusiasts like yourself. The lectures are held in Google+ Hangouts, with course assignments and homework assigned via Moodle.
The instructors are likely well-known to UT readers. Research assistant and blogger Ray Sanders (Dear Astronomer and UT) will be teaching the stellar evolution class and astronomer and writer Dr. Matthew Francis will be leading the cosmology course.
The cost for the class is $240, and the class is limited to 8 participants, with the possibility for an additional 5 participants. Both instructors say no prior knowledge of cosmology or astronomy is needed. There will be a little math, but it will be on the high school algebra level. Concepts will be heavily emphasized.
The Sun is a fascinating topic of study, which allows solar astronomers to better understand the physical processes in other stars. During this 4-week / 8-session course, we’ll explore the Sun and Solar Evolution from an astronomer’s point of view. Our course
will begin with an overview of the Sun, and solar phenomenon. We’ll also explore how stars are formed, their lifecycles, and the
incredible events that occur when stars reach the end of their lives. The course will culminate with students doing a short presentation on a topic related to the Sun or Stellar Evolution.
Cosmology is the study of the structure, contents, and evolution of the Universe as a whole. But what do cosmologists really study? In this 8-session course, we’ll look at cosmology from an astronomy point of view: taking what seems like too big of a subject and showing how we can indeed study the Universe scientifically. The starting point is the smallest chunk of the Universe that is representative of everything we can see: the Cosmic Box.
Class level: No prior knowledge of cosmology or astronomy is needed. There will be a little math, but it will be on the high school algebra level: the manipulation of ratios and use of some important equations. The emphasis is on concepts!
This schematic image represents how light from a distant galaxy is distorted by the gravitational effects of a nearer foreground galaxy, which acts like a lens and makes the distant source appear distorted, but brighter, forming characteristic rings of light, known as Einstein rings. An analysis of the distortion has revealed that some of the distant star-forming galaxies are as bright as 40 trillion Suns, and have been magnified by the gravitational lens by up to 22 times. Credit: ALMA (ESO/NRAO/NAOJ), L. Calçada (ESO), Y. Hezaveh et al.
Recently, a multinational team of astronomers found that massive, “dusty” galaxies were churning out stars much earlier than previously believed – as early as one billion years after the Big Bang (read our article about the discovery here).
Today, March 29, 2013 at 19:00 UTC (12:00 p.m. PDT, 3:00 pm EDT) the Kavli Foundation is hosting a live Google+ Hangout: “Witnessing Starbursts in the Early Universe.” You’ll have the chance to ask your questions about starburst galaxies, the early Universe and the incredible research being conducted by the South Pole Telescope and the Atacama Large Millimeter/submillimeter Array(ALMA) in Chile. Watch live in the window below, or see the replay later if you miss it live.
Science writer Bruce Lieberman will moderate, and three members of the research team will participate:
John E. Carlstrom – Leader of the 10-meter South Pole Telescope project and Deputy Director of the University of Chicago’s Kavli Institute for Cosmological Physics.
Dan P. Marrone – Assistant Professor in the Department of Astronomy at the University of Arizona.
Joaquin D. Vieira – Leader of the multinational team studying the galaxies discovered by the South Pole Telescope, Postdoctoral Scholar at the California Institute of Technology and member of Caltech’s Observational Cosmology Group.
Submit your questions before or during the webcast via Twitter (hashtag #KavliAstro) or by email to [email protected]
A time exposure of the Allen Telescope Array. (Credit: Seth Shostak/The SETI Institute used with perimssion).
In 1888, astronomer Simon Newcomb uttered now infamous words, stating that “We are probably nearing the limit of all we can know about astronomy.” This was an age just prior to identifying faint nebulae as separate galaxies, Einstein’s theory of special and general relativity, and an era when a hypothetical substance called the aether was said to permeate the cosmos.
Newcomb would scarcely recognize astronomy today. Modern observatories span the electromagnetic spectrum and are unlocking the secrets of a universe both weird and wonderful. Modern day astronomers rarely peer through an eyepiece, were it even possible to do so with such bizarre instruments. What follows are some of the most unique professional ground-based observatories in operation today that are pushing back our understanding of the universe we inhabit.
VERITAS: Based at the Fred Lawrence Whipple Observatory in southern Arizona, the Very Energetic Radiation Imaging Telescope Array System (VERITAS) is an observatory designed to observe high energy gamma-rays. Its array consists of four 12-metre aperture reflectors each comprised of 350 mirror scintillators. Each VERITAS array has a 3.5° degree field of view and the array has been fully operational since 2007. VERITAS has been used to study active galactic nuclei, gamma-ray bursts, and the Crab Nebula pulsar.
Looking down one of IceCube’s detector bore holes. (Credit: IceCube Collaboration/NSF).
IceCube: Not the rapper, IceCube is a neutrino detector in based at the Amundsen-Scott South Pole Station in Antarctica. IceCube watches for neutrino interactions by use of thousands of photomultipliers suspended up to 2.45 kilometres down into the Antarctic ice sheet. With a total of 86 detector strings completed in 2011, IceCube is currently the world’s largest neutrino observatory and is part of the worldwide Supernova Early Warning System. IceCube will also complement WMAP and Planck data and can actually “see” the shadowing effect of the Moon blocking cosmic ray muons.
Liquid Mirror Telescopes: One of the more bizarre optical designs out there in the world of astronomy, liquid mirror telescopes employ a large rotating dish of mercury to form a parabolic mirror. The design is cost effective but does have the slight drawback of having to aim directly at the zenith while a swath of sky passes over head. NASA employed a 3-metre liquid mirror telescope as part of its Orbital Debris observatory based near Cloudcroft, New Mexico from 1995-2002. The largest one in the world (and the 18th largest optical telescope overall) is the 6-metre Large Zenith Telescope in the University of British Columbia’s Malcolm Knapp Research Forest.
An aerial view of LIGO Hanford. (Credit: Gary White/Mark Coles/California Institute of Technology/LIGO/NSF).
LIGO: Designed to detect incoming gravity waves caused by pulsar-black hole mergers, the Laser Interferometer Gravitational-Wave Observatory (LIGO) is comprised of a pair of facilities with one based in Hanford, Washington and another in Livingston, Louisiana. Each detector is consists of a pair of 2 kilometre Fabry-Pérot arms and measures a laser beam shot through them with ultra-high precision. Two geographically separate interferometers are needed to isolate out terrestrial interference as well as give a direction of an incoming gravity wave on the celestial sphere. To date, no gravity waves have been detected by LIGO, but said detection is expected to open up a whole new field of astronomy.
The VLBA antenna located at St. Croix in the Virgin Islands. (Credit: Image courtesy of the NRAO/AUI/NSF).
The Very Long Baseline Array: A series of 10 radio telescopes with a resolution the size of a continent, the Very Long Baseline Array (VLBA) employs observatories across the continental United States, Saint Croix in the U.S. Virgin Islands, and Mauna Kea, Hawaii. This is effectively the longest radio interferometer in the world with a baseline of over 8,600 kilometres and a resolution of under one milliarcseconds at 4 to 0.7 centimetre wavelengths. The VLBA has been used to study H2O megamasers in Active Galactic Nuclei and measure ultra-precise positions and proper motions of stars and galaxies.
LOFAR: Located just north of the town of Exloo in the Netherlands, The LOw Frequency Radio Array is a phased array 25,000 antennas with an effective collection area of 300,000 square metres. This makes LOFAR one of the largest single connected radio telescopes in existence. LOFAR is also a proof on concept for its eventual successor, the Square Kilometre Array to be built jointly in South Africa, Australia & New Zealand. Key projects involving LOFAR include extragalactic surveys, research into the nature of cosmic rays and studies of space weather.
One of the water tank detectors in Pierre Auger observatory. (Wikimedia Image in the Public Domain).
The Pierre Auger Observatory: A cosmic ray observatory located in Malargüe, Argentina, the Pierre Auger Observatory was completed in 2008. This unique instrument consists of 1600 water tank Cherenkov radiation detectors spaced out over 3,000 square kilometres along with four complimenting fluorescence detectors. Results from Pierre Auger have thus far included discovery of a possible link between some of the highest energy events observed and active galactic nuclei.
The GONG installation at the Cerro Tololo Interamerican observatory in Chile. (Credit: GONG/NSO/AURA/NSF).
GONG: Keeping an eye on the Sun is the goal of the Global Oscillation Network Group, a worldwide network of six solar telescopes. Established from an initial survey of 15 sites in 1991, GONG provides real-time data that compliments space-based efforts to monitor the Sun by the SDO, SHO, and STEREO A & B spacecraft. GONG scientists can even monitor the solar farside by use of helioseismology!
The Allen Telescope Array: Located at Hat Creek 470 kilometres northeast of San Francisco, this array will eventually consist of 350 Gregorian focus radio antennas that will support SETI’s search for extraterrestrial intelligence. 42 antennas were made operational in 2007, and a 2011 budget shortfall put the status of the array in limbo until a preliminary financing goal of $200,000 was met in August 2011.
The YBJ Cosmic Ray Observatory: Located high on the Tibetan plateau, Yangbajing International Cosmic Ray Observatory is a joint Japanese-Chinese effort. Much like Pierre-Auger, the YBJ Cosmic Ray Observatory employs scintillators spread out along with high speed cameras to watch for cosmic ray interactions. YBJ observes the sky in cosmic rays continuously and has captured sources from the Crab nebula pulsar and found a correlation between solar & interplanetary magnetic fields and the Sun’s own “cosmic ray shadow”. The KOSMA 3-metre radio telescope is also being moved from Switzerland to the YBJ observatory in Tibet.
