Artist’s impression of a very distant quasar powered by a black hole with a mass two billion times that of the Sun. (Image: ESO/M. Kornmesser via Wikimedia Commons)

Scientists have found the largest known structure in the universe, a cluster of galactic cores so vast it would take four billion years for a spacecraft traveling at the speed of light to cross it.

The sighting challenges a theory from Einstein which suggests such a massive object shouldn’t exist in the universe.

A quasar is the compacted center of a galaxy surrounding a massive black hole from the early days of the universe.  Quasars  go through periods of extreme brightness which can last anywhere from 10 to 100 million years. They tend to band together in enormous clusters, or structures, forming large quasar groups (LQGs).

The international group of scientists led by Roger Clowes from the University of Central Lancashire’s Jeremiah Horrocks Institute, used data from the Sloan Digital Sky Survey (SDSS), a major surveying project that uses 2.5-m wide-angle optical telescope located at New Mexico’s Apache Point Observatory, to make their findings.

Clowes and his colleagues are astounded by the size of this structure, which defies the Cosmological Principal, based on Albert Einstein’s theory of General Relativity that assumes when you look at the universe from a sufficiently large scale; it looks the same no matter where you are observing it from.  The Cosmological Principle, according to the research team, is assumed but has never been demonstrated observationally ‘beyond reasonable doubt.’

Large quasar group (LQG) as imaged by the Big Throughput Camera at the Cerro Tololo Inter-American Observatory in Chile (Photo: Chris Haines)

“While it is difficult to fathom the scale of this LQG, we can say quite definitely it is the largest structure ever seen in the entire universe,” said Clowes. “This is hugely exciting, not least because it runs counter to our current understanding of the universe. The universe doesn’t seem to be as uniform as we thought.”

Clusters of galaxies can be anywhere from six to 10 million light-years across, but the LQGs can be 650 million light-years or more across. Making calculations based on the Cosmological Principle, along with the modern theory of cosmology, astrophysicists shouldn’t be able to find a structure in the universe larger than 1.2 billion light-years, much less four billion light-years across as this newly sighted structure is.

To get some additional perspective of what the astronomers found, let’s step back and give it a sense of scale.  Our own galaxy, the Milky Way, is separated from its nearest neighbor, the Andromeda Galaxy, by a distance of 2.5 million light-years.

Clowes points out that his team’s discovery does have a typical dimension of 1.6 billion light-years. But, because it is elongated, its longest dimension is four billion light-years, making it about 1,650 times larger than the distance from the Milky Way to Andromeda.

Composite image of the galaxy cluster which helped reveal the newly discovered galaxy – MACS0647-JD. The inset at left shows a close up of the young dwarf galaxy. (NASA)

Scientists have discovered what could be the oldest, most distant galaxy in the universe, thanks to a unique combination of man-made and natural telescopes.

The newly discovered galaxy, MACS0647-JD, was found by the Cluster Lensing And Supernova Survey with Hubble (CLASH).

It is about 13.3 billion light years, or 125,825,000,000,000,000,000,000 km, from Earth. Scientists are getting to see it just as it was 420 million years after the Big Bang, or when the universe was only three percent of its current age of about 13.7 billion years.

Astronomers made the discovery by combining the power of the Hubble Space Telescope, the Spitzer Space Telescope and a natural zoom effect called gravitational lensing, which uses enormous galaxy clusters as interstellar telescopes to magnify distant galaxies behind them.

The effect is achieved when the light rays from the distant object are bent by the gravity of the huge galaxy clusters, just like a giant cosmic lens, that lie between the object and  Earth.

“While one occasionally expects to find an extremely distant galaxy using the tremendous power of gravitational lensing, this latest discovery has outstripped even my expectations of what would be possible with the CLASH program,” said Rychard Bouwens of Leiden University in the Netherlands, a co-author of the study that outlined the discovery. “The science output in this regard has been incredible.”

The massive galaxy cluster that’s making the distant galaxy appear brighter than it normally would, providing the natural boost to the Hubble and Spitzer telescopes, , is called MACS J0647.7+7015 and is about five billion light years away.

Hubble in orbit above the Earth (Photo: NASA)

Because of the gravitational lensing provided by the cluster, the CLASH team was able to observe three magnified images of MACS0647-JD with the Hubble.

“This cluster does what no man-made telescope can do,” said Marc Postman of the Space Telescope Science Institute, who leads the CLASH team. “Without the magnification, it would require a Herculean effort to observe this galaxy.”

The astronomers say that the distant galaxy is so small, about 600 light years across according to their observations that it may be going through its first stages formation. Our own Milky Way galaxy is about 150,000 light years across.

“This object may be one of many building blocks of a galaxy,” says Dan Coe from the Space Telescope Institute and lead author of the study.  “Over the next 13 billion years, it may have dozens, hundreds, or even thousands of merging events with other galaxies and galaxy fragments.”

The galaxy could turn out to be too far away for astronomers to confirm its distance with any of the current available technology.  But once the new James Webb Space Telescope launches in 2018, astronomers expect to be able to take a definitive measurement of its distance and to study the properties of the galaxy in more detail.

MACS0647-JD, is very young and only a tiny fraction of the size of our Milky Way. The object is observed 420 million years after the big bang.   (Video: NASA, ESA, and G. Bacon (STScI))

The farthest-ever view of the universe. Hubble’s “extreme Deep Field (XDF) is a composite made from 2,000 images, taken by the Hubble Space Telescope over a 10 year period. (Credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team)

The Hubble Space Telescope has given us  the deepest view of space ever.

Called the eXtreme Deep Field, or XDF, it’s a composite of more than 2,000 photos taken by Hubble over 10 years.

“The XDF is the deepest image of the sky ever obtained and reveals the faintest and most distant galaxies ever seen. XDF allows us to explore further back in time than ever before,” said Garth Illingworth of the University of California at Santa Cruz, principal investigator of the Hubble Ultra Deep Field 2009 (HUDF09) program.

Hubble’s Advanced Camera for Surveys and its Wide Field Camera 3 focused on a tiny spot of the southern sky, which was found in the center of the original Hubble Ultra Deep Field (UDF), a composite created from Hubble Space Telescope data gathered from 2003 and 2004.

While the images that made up the UDF revealed thousands of near and very distant galaxies, the newly released full-color XDF image reaches much fainter galaxies.  NASA scientists say the new XDF also contains about 5,500 galaxies which were taken within a smaller field of view than the UDF.

In creating the XDF,  astronomers were able to use very deep exposures in red light  taken by Hubble’s new infrared camera, which was installed by the Space Shuttle Atlantis in 2009. The data and images taken by the new camera will allow astronomers to study some of the earliest galaxies in the universe. The faintest galaxies in the XDF are one ten-billionth the brightness of what the human eye can see, according to NASA.

This illustration separates the XDF into three planes showing foreground, background, and very far background galaxies. These divisions reflect different epochs in the evolving universe. (Image: NASA, ESA, and Z. Levay, F. Summers (STScI))

The XDF not only provides a unique view of some of the deepest recesses of space but  also serves as a “time tunnel into the distant past.”

The universe is believed to be 13.7 billion years old, and the XDF shows galaxies that go back some 13.2 billion years, less than 500 million years after the Big Bang. The youngest galaxy found in the XDF existed just 450 million years after the birth of the universe.

The XDF will give astronomers the opportunity to view and study those ancient galaxies when they were young, small and growing.

If you would like to learn more about the eXtreme Deep Field, the Space Telescope Science Institute (STScI), which operates the science program for the Hubble Space Telescope, is inviting the public to an online seminar  Thursday, September 27, at 1700 UTC.

Three  astronomers from the XDF observing team will describe how they assembled the spectacular image and explain what it tells us about the evolving universe.  Participants can send in questions for the panel of experts. To participate, visit hubblesite.org.

This video explains how astronomers meticulously assembled mankind’s deepest view of the universe from combining Hubble Space Telescope exposures taken over the past decade. Guest scientists are Dr. Garth Illingworth and Dr. Marc Postman.  (Video: NASA, ESA, and M. Estacion and G. Bacon (STScI))

Taken from stills of a simulation of the universe’s evolution, this is a visualization of large-scale structures in the universe over time. (Photo: Habib et al./Argonne National Lab)

Since they can’t turn back time to witness the creation of the universe almost 14 billion years ago, scientists are working on the next best thing: creating a virtual universe, starting at the beginning with the Big Bang.

With the help of the world’s third^-fastest computer, physicists from the US Department of Energy’s Argonne National Laboratory are developing  simulations that will take them on a trip from the origins of the universe until today.

This is a mosaic of the images covering the entire sky as observed by the Wide-field Infrared Survey Explorer (WISE).  Sky surveys such as this will be used to create simulations of the universe. (Image: NASA/JPL-Caltech/UCLA)

Over the years, scientists have scanned the night skies with telescopes which produced maps of the universe.  With the advances in astronomical technology, more details about the cosmos have emerged from these surveys.

Taking data from the best sky surveys and running it through Argonne’s Mira Supercomputer, the team plans to produce some of the largest high-resolution simulations of the distribution of matter in the universe.

Given the improvements in technology, Salman Habib, one of the project leaders, says it makes sense to try to understand  the universe  on the biggest possible scale.

“In effect, all of science, as you know it, can be studied by looking at the evolution of the universe,” says Habib.

The planned simulation, according to Katrin Heitmann, a co-leader on the project, will include  images and movies of the universe at different times.  Scientists who use the team’s recreation of the universe for their own cosmological research will be able to gather information taken and measured from the statistics produced by the simulation.

Scientists hope the project will help shed greater light on Dark Matter, a theoretical form of matter scientists believe accounts for much of the total mass in the universe.

Habib points out that we’re used to thinking of space as something static or fixed, but as time progresses new space continues to be created. The expansion of the universe is predicted by Einstein’s general theory of relativity, but that same theory, according to Habib, also states that that expansion should slow down with time.

Albert Einstein (circa 1921) theorized  the expansion of the universe slows over time.  However, recent observations suggest the opposite might be true and that the universe is continuing to expand.  (Photo: Creative Commons/Wikipedia)

However, observations made over recent years, including work by winners of the Nobel Prize in Physics in 2011,  show the opposite is true, that in fact, the universe is expanding at an accelerated rate.

The cause of this expansion remains a mystery, according to Habib, but a number of scientists think  Dark Energy is the force behind the universe’s rapid growth.

The team also hopes to learn more about Dark Energy, the hypothetical form of energy thought to compose about 70 percent of the universe .

According to Habib, scientists are unsure exactly what Dark Energy is.

To help solve this mystery,  different models of what Dark Energy could be will be put through the simulation to allow scientists to compare the observational results of each model.

Habib and his colleagues hope their simulations will not only help scientists check various models of Dark Energy, and the properties of Dark Matter, but will also provide a kind of grand picture of the evolution of the universe.

Project leaders Habib and Heitmann join us this weekend on the radio edition of Science World to talk about creating a virtual universe.

Check out the right column for scheduled air-times or listen now to the interview below.

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(Photo: NASA, M.Masetti)

If you think you have what it takes to build a satellite, NASA has just introduced an online game that might appeal to you.

With “Build It Yourself: Satellite!” the US space agency offers users the chance to act as engineers and astronomers who conceive and build their own special virtual satellite.

“It’s fun to play,” says Maggie Masetti, a NASA webmaster who created the game. “And users will learn something about satellite instrumentation and optics and how they are used to make scientific discoveries, as well about a large range of different existing astronomical missions.”

The game lets players choose what kind of science their satellite will study. They can then customize the sophisticated technical aspects of their satellite – such as what wavelengths their creation will operate at and what kind of tools, instruments and optics will give them the best opportunity to learn as much as possible about their chosen science.

Artist conception of James Webb Space Telescope (Image: NASA)

A number of astronomical missions, some dating back to 1980s, are available to game players.  You can go from rather small x-ray telescopes, like NASA’s Rossi X-ray Timing Explorer, to the much larger and popular  Hubble Space Telescope.

The game is available in two sizes so players can choose the one better suited to their monitor.  If you’re stuck with a slower computer, the game offers a special toggle button that will reduce the quality of the graphics but will make the game run faster.

The new gaming experience was inspired by the James Webb space telescope, which is being built now and is scheduled for launch in 2018.

Said to have the latest cutting-edge technology, the Webb space telescope will help scientists expose the secrets of the universe by taking them far back in time, toward the Big Bang.  Webb will be the most powerful telescope ever built by the space agency.

Who knows, maybe after playing “Build It Yourself: Satellite!” you’ll realize you have the talent and ability to become a real-life rocket scientist!

Time-lapse of the construction of the giant structural steel frame that will be used to assemble the mirrors and instruments of the James Webb Space Telescope.