SPIDER: 'Spacecraft' seeks traces of the early universe over Antartica

Constructed primarily in Princeton's Jadwin Hall, SPIDER is a stratospheric spacecraft that in December will begin a 20-day orbit in Earth's stratosphere at an altitude of roughly 110,000 feet.

During that period, SPIDER's six large cameras will look for the pattern, or polarization, of gravitational waves produced by the fluctuation of energy and density that resulted from the Big Bang.

These waves, explained William Jones a Princeton University assistant professor of physics, are a "statistically unique fingerprint" that can be traced back to the beginning of the universe.

Many astronomical instruments measure various characteristics of this fingerprint, SPIDER is designed to characterize the "shape" of it, said Jones, who is the project's principal investigator.

"The ultimate goal of SPIDER is to see to what extent we can identify a very characteristic feature in that polarization that's expected to come from the earliest stages of the evolutionary growth of our universe," Jones said.

"There's a very particular pattern than can be generated only by something like a gravitational wave propagating through the surface of the cosmic microwave background [which is the glow of the heat left over from the Big Bang]," Jones said.

"That is a very particular pattern commonly referred to as a 'pinwheel' pattern on the sky. It's that particular pinwheel pattern that we're really after."

SPIDER, which used to be an acronym, but now is the project's formal name, is a multi-institutional project funded largely by a grant from NASA, as well as the David and Lucille Packard Foundation.

In addition to Princeton, the primary institutions involved are the University of Toronto; Case Western Reserve University; the California Institute of Technology and the Jet Propulsion Laboratory, a NASA-funded research center managed by Caltech; and the University of British Columbia.

The project was proposed in 2006 while Jones, who joined Princeton's faculty in 2008, was a scientist at the Jet Propulsion Laboratory.

Galaxy Segue 1 study suggests it is a fossil from the early universe

The portion of sky in which astronomers found the Segue 1 dwarf galaxy. 

Credit: Marla Geha/W.M. Keck Observatory.

A trio of space researchers studying the galaxy Segue 1 has found that its red giant stars are made mostly of hydrogen and helium, with very few heavy elements, suggesting the galaxy stopped evolving not long after its formation.

In their paper uploaded to the preprint sever arXiv (and soon to be published in Astrophysical Journal) the team describes observation data they've obtained regarding the galaxy and why what they've found might mean Segue 1 is the oldest observable galaxy in the night sky.

Scientists have known about Segue 1 for some time, it's both close to us (just 75,000 light years away) and very small, with just few hundred stars.

In this new effort, Anna Frebel with MIT, Joshua Simon with Carnegie Mellon University and Evan Kirby with the University of California studied the makeup of red giants in Segue 1 and found they are made up mostly of hydrogen and helium.

This implies that the stars came about due to the explosions of massive stars, prior research has shown that it's smaller star explosions that result in new stars forming heavy with metals (because the smaller stars create the heavier elements).

Prior research has also shown that higher mass stars tend to blow up at a much younger age than low mass stars.

Also when stars explode in general, they release material that winds up being used in new star formation. As the process repeats, more stars with heavy metals are created.

But not Segue 1, for some reason the evolution process simply stopped, leaving the galaxy in very nearly the same condition it was shortly after forming.

Why this happened is a mystery, though there is one theory, it's based on reionization.

Reionisation theory suggests that shortly after the universe was born, ionized gasses began to cool allowing the formation of atoms and eventually stars.

Those stars eventually blew up releasing radiation that served as fuel for more reionisation.

New stars cannot form from ionized gasses, of course, so if certain parts of space had stars that caused a lot of reionisation, the creation of new stars would have been impossible, the evolution of such a galaxy would simply stop.

Thus far, Segue 1 is the only such galaxy to have been found, but if the reionisation theory is correct, it's likely there are many more, researchers just can't see them because they are too far away.

More information: Segue 1: An Unevolved Fossil Galaxy from the Early Universe, arXiv:1403.6116 [astro-ph.GA] arxiv.org/abs/1403.6116

Hubble UDS: Ancient Granny galaxies discovered in the early universe

UDS (UKIDDS Ultra Deep Survey) astronomical field, with four of the 15 mature galaxies, based on the infrared light of NASA's Hubble Space Telescope. 

The galaxies exhibit the typical red colours of mature galaxies. 

Most of the other galaxies in the image are much closer. 

Credit: Caroline Straatman.

An international team of astronomers have discovered the most distant examples of galaxies that were already mature and massive – not just young, star-forming galaxies in the nursery-room of the early Universe but also old, 'retired' ones – 'granny galaxies'.

Lee Spitler

A new paper, published in the Astrophysical Journal Letters by researchers from Macquarie University, the Australian Astronomical Observatory (AAO) and Swinburne University of Technology raises new questions about the early Universe, and what forced these mature galaxies to grow up so quickly.

"Scientists have known about large numbers of young galaxies in the early universe actively forming new stars," says co-author Dr Lee Spitler.

Caroline Straatman

"The ones we've found have already gone through this phase: they have actually taken an early retirement from star-formation, when the universe was only 12% of its current age.

Because they grew up so quickly, it's likely they underwent an explosive period of new star formation – a brief, so called starburst phase – then retired."

Dr Lee Spitler, a joint appointment between Macquarie University and the AAO, joined the team in using deep images at near-infrared wavelengths to search for galaxies in the early universe with red colors.

The characteristic red colours indicate the presence of old stars and a lack of active star formation.

Karl Glazebrook

"These distant and early massive galaxies are one of the Holy Grails of astronomy," Professor Karl Glazebrook, Director of the Centre for Astrophysics and Supercomputing at Swinburne University of Technology, said.

"Fifteen years ago they were predicted not to even exist within the cosmological model favoured at the time."

"In 2004 I wrote a paper on the discovery of such galaxies existing only three billion years after the Big Bang."

"Now, with improved technology we are pushing back to only 1.6 billion years, which is truly exciting."

FourStar camera on the Magellan Baade

The galaxies were discovered after 40 nights of observing with the FourStar camera on the Magellan Baade Telescope in Chile and combined with data from Hubble's Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and the Great Observatories Origins Deep Survey (GOODS).

Using special filters to produce images that are sensitive to narrow slices of the near-infrared spectrum, the team were able to measure accurate distances to thousands of distant galaxies at a time, providing a 3-D map of the early universe.

More information: "A substantial population of massive quiescent galaxies at z~4 from ZFOURGE," Astrophysical Journal Letters, 18 February 2014, C. Straatman, I. Labbé, L. Spitler, R. Allen, et al: DOI: 10.1088/2041-8205/783/1/L14

Early universe 'warmed up' later than previously believed

A new study from Tel Aviv University reveals that black holes, formed from the first stars in our universe, heated the gas throughout space later than previously thought. 

They also imprinted a clear signature in radio waves which astronomers can now search for. 

The work is a major new finding about the origins of the universe.

"One of the exciting frontiers in astronomy is the era of the formation of the first stars," explains Prof. Rennan Barkana of TAU's School of Physics and Astronomy, an author of the study.

Rennan Barkana

"Since the universe was filled with hydrogen atoms at that time, the most promising method for observing the epoch of the first stars is by measuring the emission of hydrogen using radio waves."

The study, just published in the journal Nature, was co-authored by Dr. Anastasia Fialkov of TAU and the École Normale Supérieure in Paris and Dr. Eli Visbal of Columbia and Harvard Universities.

Cosmic archaeology
Astronomers explore our distant past, billions of years back in time. Unlike Earth-bound archaeologists, however, who can only study remnants of the past, astronomers can see the past directly.

The light from distant objects takes a long time to reach the earth, and astronomers can see these objects as they were back when that light was emitted.

Anastasia Fialkov

This means that if astronomers look out far enough, they can see the first stars as they actually were in the early universe.

Thus, the new finding that cosmic heating occurred later than previously thought means that observers do not have to search as far, and it will be easier to see this cosmic milestone.

Cosmic heating may offer a way to directly investigate the earliest black holes, since it was likely driven by star systems called "black-hole binaries."

These are pairs of stars in which the larger star ended its life with a supernova explosion that left a black-hole remnant in its place.

Gas from the companion star is pulled in towards the black hole, gets ripped apart in the strong gravity, and emits high-energy X-ray radiation.

This radiation reaches large distances, and is believed to have re-heated the cosmic gas, after it had cooled down as a result of the original cosmic expansion.

The discovery in the new research is the delay of this heating.

More information: 'The observable signature of late heating of the Universe during cosmic reionization' dx.doi.org/10.1038/nature12999

Early universe was less dusty than believed

Credit: Swinburne University of Technology

Dust may be more rare than expected in galaxies of the early Universe, according to an international research team, led by Swinburne University of Technology astrophysicist Dr David Fisher.

In a galaxy named IZw 18, the team measured the lowest dust mass of a galaxy that has ever been measured.

"It's not just that the dust mass is low. We found that the dust mass is 100 times smaller than would be expected based on commonly assumed theories," Dr Fisher said.

The galaxy, I Zw 18, is nearby, which makes it easier to study, but has properties that are very similar to galaxies of the high redshift Univese.

"It's an extreme galaxy in the local Universe, but it tells us a lot about a stage that almost all galaxies have gone through, so it gives us a picture of what the first galaxies look like."

Dr Fisher said the results imply that galaxies of the early Universe may have less dust than has been expected.

"This means, firstly, that they will look different than we expect and make different populations of stars than we expect."

The Atacama Compact Array (ACA) is a sub-system of the ALMA telescope which allows enhanced imaging fidelity especially for extended astronomical sources. 

The ACA comprises of 16 (four 12-m and twelve 7-m) antennas, the last of which was delivered by Japan in May, 2012. 

Credit: ALMA(ESO/NAOJ/NRAO), R. Hills

"Secondly, that they will be much more difficult to observe, even with state-of-the-art facilities being built now such as the Atacama Large Millimeter/sub-millimeter Array (ALMA) of radio telescopes in northern Chile.

"IZw 18 is typical of very high redshift galaxies because it is very actively forming stars, and has a chemistry that is more like galaxies of the very early Universe with a very low abundance of metals and a lot of gas in the form of hydrogen," he said.

"Our result implies that current theories to describe the formation of stars when the Universe was very young are incomplete, and are built on invalid assumptions."

According to Dr Fisher, the amount of dust is very important for the formation of stars.

"What we think is going on, is that the harsh environment inside the galaxy we examined is adversely affecting the amount of dust in it.

"The radiation field measured inside I Zw 18 was roughly 200 times stronger than what we experience here in the Milky Way."

Dr Fisher said that based on the findings, theories should be amended to account for environment in making stars.

The research is published in Nature.

More information: Paper: dx.doi.org/10.1038/nature12765

Ultracold Big Bang Experiment Simulates Evolution of Early Universe

Scientists created this detailed, all-sky picture of the infant universe from nine years of data from the orbiting Wilkinson Microwave Anisotropy Probe. 

The image reveals 13.77 billion year old temperature fluctuations—shown as color differences—that correspond to the seeds that grew to become the galaxies. 

Physicists now are using clouds of ultracold atoms in a vacuum chamber to simulate the growth of structure in the early universe. 

Credit: NASA/WMAP Science Team

Physicists have reproduced a pattern resembling the cosmic microwave background radiation in a laboratory simulation of the big bang, using ultracold cesium atoms in a vacuum chamber at the University of Chicago.

"This is the first time an experiment like this has simulated the evolution of structure in the early universe," said Cheng Chin, professor in physics.

Cheng Chin

Chin and his associates reported their feat in the Aug. 1 edition of Science Express, and it will appear soon in the print edition of Science.

Chin pursued the project with lead author Chen-Lung Hung, PhD'11, now at the California Institute of Technology, and Victor Gurarie of the University of Colorado, Boulder.

Their goal was to harness ultracold atoms for simulations of the big bang to better understand how structure evolved in the infant universe.

The cosmic microwave background is the echo of the big bang. Extensive measurements of the CMB have come from the orbiting Cosmic Background Explorer in the 1990s, and later by the Wilkinson Microwave Anisotropy Probe and various ground-based observatories, including the UChicago-led South Pole Telescope collaboration.

These tools have provided cosmologists with a snapshot of how the universe appeared approximately 380,000 years following the Big Bang, which marked the beginning of the universe.

It turns out that under certain conditions, a cloud of atoms chilled to a billionth of a degree above absolute zero (-459.67 degrees Fahrenheit) in a vacuum chamber displays phenomena similar to those that unfolded following the big bang, Hung said.

"At this ultracold temperature, atoms get excited collectively. They act as if they are sound waves in air," he said.

The dense package of matter and radiation that existed in the very early universe generated similar sound-wave excitations, as revealed by COBE, WMAP and the other experiments.

The synchronized generation of sound waves correlates with cosmologists' speculations about inflation in the early universe.

"Inflation set out the initial conditions for the early universe to create similar sound waves in the cosmic fluid formed by matter and radiation," Hung said.

Journal Reference:
C.-L. Hung, V. Gurarie, C. Chin. From Cosmology to Cold Atoms: Observation of Sakharov Oscillations in a Quenched Atomic Superfluid. Science, 2013; DOI: 10.1126/science.1237557

Sky Survey Map of Massive Galaxies, Distant Black Holes, Clues to Dark Matter and Energy

The Sloan Digital Sky Survey III(SDSS-III) has released the largest-ever three-dimensional map of massive galaxies and distant black holes, helping astronomers better explain the mysterious “dark matter” and “dark energy” that make up 96 percent of the universe. 

According to SDSS-III scientific spokesperson and University of Pittsburgh assistant professor of physics and astronomy Michael Wood-Vasey, scientists using the map, titled Data Release 9 (DR9), can retrace the Universe’s history over the last seven billion years. 

Wood-Vasey co-wrote the DR9 summary paper featured on the arXiv database.

“This is science at its collaborative best,” said Wood-Vasey. “SDSS-III scientists work together to address big questions extending from our own galaxy to distant reaches of the Universe, and then they share that data with the world to allow anyone to make the next big discovery.”

The new DR9 map of the Universe includes images of 200 million galaxies and spectra measurements of how much light galaxies gives off at different wavelengths— of 1.35 million galaxies, including new spectra of 540,000 galaxies dating from when the universe was half its present age.

Researchers at SDSS-III say that studying spectra is important because it allows scientists to figure out how much the Universe has expanded since the light left each galaxy.

Additionally, having this new data to analyze not only helps researchers understand the distant Universe, and the Earth’s own Milky Way Galaxy.

DR9 includes better estimates regarding the temperatures and chemical compositions of more than a half million stars in the Milky Way.

DR9 represents the latest in a series of data releases stretching back to 2001. This release includes new data from the ongoing SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), which will eventually measure the positions of 1.5 million massive galaxies over the past seven billion years of cosmic time, as well as 160,000 quasars—giant black holes feeding on stars and gas—from as long ago as 12 billion years.

While all of these new images and spectra contain the promise of new discoveries about the universe, SDSS-III is only in the middle of its six-year survey and will release three times as much data by the time it has completed its work, in 2014.

All the newly released data is now available on the DR9 Web site, at http://www.sdss3.org/dr9.

Additionally, the SkyServer Web site includes lesson plans for teachers who use DR9 data to teach astronomy and other topics in science, technology, and mathematics.

Cosmic Background radiation (CMB): No evidence for 'knots' in space

The new study, published in Physical Review Letters, places the best limits available on theories that produce textures, ruling out at 95% confidence theories that produce more than six detectable textures on our sky.

Theories of the primordial Universe predict the existence of knots in the fabric of space - known as cosmic textures - which could be identified by looking at light from the cosmic microwave background (CMB), the relic radiation left over from the Big Bang.

Using data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP) satellite, researchers from UCL, Imperial College London and the Perimeter Institute have performed the first search for textures on the full sky, finding no evidence for such knots in space.

As the Universe cooled it underwent a series of phase transitions, analogous to water freezing into ice. Many transitions cannot occur consistently throughout space, giving rise in some theories to imperfections in the structure of the cooling material known as cosmic textures.

If produced in the early Universe, textures would interact with light from the CMB to leave a set of characteristic hot and cold spots.

If detected, such signatures would yield invaluable insight into the types of phase transitions that occurred when the Universe was a fraction of a second old, with drastic implications for particle physics.

A previous study, published in Science in 2007, provided a tantalising hint that a CMB feature known as the "Cold Spot" could be due to a cosmic texture. However, the CMB Cold Spot only comprises around 3% of the available sky area, and an analysis using the full microwave sky had not been performed.

The new study, published in Physical Review Letters, places the best limits available on theories that produce textures, ruling out at 95% confidence theories that produce more than six detectable textures on our sky.

Stephen Feeney, from the UCL Department of Physics and Astronomy and lead author, said: "If textures were observed, they would provide invaluable insight into the way nature works at tremendous energies, shedding light on the unification of the physical forces.

"The tantalizing hints found in a previous small-scale search meant it was extremely important to carry out this full-sky analysis."

Co-author Matt Johnson, from the Perimeter Institute, Canada, said: "Although there is no evidence for these objects in the WMAP data, this is not the last word: in a few months we will have access to much better data from the Planck satellite.

"Whether we find textures in the Planck data or further constrain the theories that produce them, only time will tell!"
 
"A robust constraint on cosmic textures from the cosmic microwave background" is published in the journal Physical Review Letters on 12 June 2012.

Big Bang Aftermath: From Darkness to Light

An international team of scientists has found a clue as to what happened in the universe after the Big Bang.

They claim that just after the big bang, a dense hydrogen fog that was seen across the universe was completely burned off in some isolated, low-density regions of the universe.

A few hundred million years later, reionisation took place in the dense, crowded regions of the universe.

Previously, astronomers claimed that just after big bang, a dense hydrogen "fog" settled over the universe. During this time, a lot of the light produced by the first stars could only travel short distances before it was absorbed by the fog.

They call this period the "dark ages" of the universe, but little is known about what was happening at this time.

Now scientists have found that hydrogen fog was burned off first in isolated, low-density regions of the universe. They also found that galaxies in crowded regions of the universe were more likely to be shrouded in very dense pockets of hydrogen fog.

Such dense regions would therefore require larger numbers of light sources and more time to burn off the fog compared to regions with relatively light fog.

Scientists discovered this when they studied several reionisations that took place around three galaxies, including the Milky Way.

"We used nearby galaxies to understand something that happened long ago, in much the same way fossils are used to understand earth's history," said Duncan Forbes, professor at the Swinburne University of Technology.

"We can see regions around galaxies where reionisation has just finished and use that information to understand important questions about the dark ages: What were the first stars like; how were the first galaxies formed; and were there many supermassive black holes," he added.

"Understanding how reionisation moved through the universe is very challenging but of enormous importance in astronomy.

Our technique provides a novel way to tackle this problem," said Dr Lee Spitler, astrophysicist at the Swinburne University of Technology, in a statement.

Scientists claim that further studies will help them understand more about the dark ages and the evolution of the universe.

Dark Matter Ideas Challenged by Galaxy Structures

The galaxy pair UGC 9618 and VV 340, two spiral galaxies at the beginning of a collision.

CREDIT: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)

A sprawling collection of galaxies and star clusters surrounding our own Milky Way is challenging long-standing theories on the existence of dark matter, the mysterious substance thought to pervade the universe.

The structure of satellite galaxies and star clusters around the Milky Way is so vast that it reaches across a million light-years – 10 times as wide as the Milky Way itself, according to astronomers at the University of Bonn in Germany, who made the discovery.

Existing dark matter theories fail to explain the arrangement of these cosmic objects, the scientists say.

"Our model appears to rule out the presence of dark matter in the universe, threatening a central pillar of current cosmological theory," said study team member Pavel Kroupa, a professor of astronomy at the University of Bonn.

"We see this as the beginning of a paradigm shift, one that will ultimately lead us to a new understanding of the universe we inhabit."

H3+: The Molecule that Made the Universe

The molecule known as H3+ is believed to have had a vital role in cooling down the first stars of the universe, and may still play an important part in the formation of current stars. Above, new stars burst into being in the star-forming nebula Messier 78, imaged by NASA's Spitzer Space Telescope. (Image credit: NASA/JPL-Caltech)

In a study that pushed quantum mechanical theory and research capabilities to the limit, UA researchers have found a way to see the molecule that likely made the universe - or at least the hot and fiery bits of it.

Lurking in the vast, chilly regions between stars, the unassuming molecule known as a triatomic hydrogen ion, or H3+, may hold secrets of the formation of the first stars after the Big Bang.

At the University of Arizona, then doctoral candidate Michele Pavanello spent months doing painstaking calculations to find a way to spot H3+ and unveil its pivotal role in astronomy and spectroscopy, supervised by Ludwik Adamowicz, a professor in the UA's department of chemistry and biochemistry.

The groundbreaking results have been published in a recent edition of Physical Review Letters.

"Most of the universe consists of hydrogen in various forms," said Adamowicz, "but the H3+ ion is the most prevalent molecular ion in interstellar space. It's also one of the most important molecules in existence."

Believed to be critical to the formation of stars in the early days of the universe, H3+ also is the precursor to many types of chemical reactions, said Adamowicz, including those leading to compounds such as water or carbon, which are essential for life.

Early stars would have become hotter and hotter until they exploded before they ever formed, according to Pavanello, unless there was a way to release some of that pent-up energy.

"There wouldn't be any star formation if there weren't molecules that slowly cool down the forming star by emitting light," said Pavanello. Not many molecules can do that, he added, partly because very few molecules existed in the early days of the universe.

"Astronomers think that the only molecule that could cool down a forming star in that particular time is H3+."

A perfect asymmetry
Another molecule, molecular hydrogen, would have been present, but it would have had a much harder time cooling a forming star than H3+. "Hydrogen does not like to emit light, while H3+ can bend and vibrate, and in doing so it is able to emit light." said Pavanello.

H3+ is an electrically charged molecule, called an ion. It consists of three hydrogen atoms with only two, as opposed to a healthy three, electrons to share between them. Lacking a negatively charged electron, the molecule takes on a plus-one positive charge.

H3+ has a triangular shape, explained Adamowicz. "As it is excited it starts to vibrate in various ways."

"One has to involve a large amount of computations at the quantum mechanical level to predict those vibrations," said Adamowicz. "The role of theory is essentially to simulate those vibrations in the computer and then describe how the molecule is swinging or dancing."

Understanding the various vibrations of H3+ could help astronomers deduce to what extent it played a role in the formation of the early stars.

"In the 1990s, H3+ was observed surrounding stars," said Adamowicz. "The stars emit radiation, which not only contributes to the production of H3+ but also excites the molecule to higher energy states. The molecule can also become excited through leftover energy from chemical reactions it was involved in or through collisions with other molecules. In the process of de-excitation the molecule emits photons that are detected by our radio telescopes."

"That can only happen with H3+ because molecular hydrogen is too symmetric," said Pavanello. "And so H3+ has a very important cooling function in the formation of the first stars after the Big Bang."

"The only way we can predict how the stars form is if we know very well what the cooling abilities of H3+ are, and we cannot know its cooling ability until we know its vibrational spectrum. We need to know what these energy levels are," said Pavanello.

"With this paper we have pinpointed the energy levels up to a certain energy threshold that is already good enough to generate accurate predictions of the cooling ability of H3+," said Pavanello.

It happened almost by chance
The group didn't set out to unlock the secrets of H3+, said Pavanello, who graduated from the UA in 2010 with a prestigious Marie Curie post-doctoral fellowship that took him to Leiden University in the Netherlands. He is now an assistant professor of theoretical chemistry at Rutgers University in Newark, N.J.

"It all happened almost by chance," he said. "A friend of the mass-spectrometry facility in the UA's chemistry department happens to be a very good quantum chemist from Hungary. He once visited the department and talked to Ludwik about the possibility to do some H3+ calculations. At the time, I had just started. The code I was writing was almost done, and we thought H3+ could be a good system on which to test this code."

The researchers input a computer code into super computers at the UA's High Performance Computing Center that described the ways in which H3+ vibrates according to quantum mechanical principles. "We couldn't have done this without their support," said Pavanello.

Depending on the level of approximations made in the computer code, said Pavanello, the researchers can develop software that can describe the motion of small molecules very well, or large molecules very approximately.

"We decided to implement something that had essentially no approximations, but of course with the price that we can only apply it to very small molecules," said Pavanello. "Our method simply did not exist before in a mainstream form."

The UA team's results were corroborated by teams from Hungary, France, London and Russia, and also by experiments done at the Max-Planck Institute in Heidelberg, Germany that created H3+ in a laboratory and verified that its spectral lines matched the predictions.

The UA team's contribution allowed the researchers for the first time to assign spectral lines of H3+ to particular types of the vibrational motions as the ion releases photons with near-visible wavelengths. These wavelengths contribute to the color of the light H3+ radiates toward us from interstellar space.

Time machine will study the early universe

With MOSFIRE, it will now become much easier to identify faint galaxies, "families of galaxies" and merging galaxies. The instrument also will enable detailed observations of planets orbiting nearby stars, star formation within our own galaxy, the distribution of dark matter in the universe and much more.

A new scientific instrument, a "time machine" of sorts, built by UCLA astronomers and colleagues, will allow scientists to study the earliest galaxies in the universe, which could never be studied before.

The five-ton instrument, the most advanced and sophisticated of its kind in the world, goes by the name MOSFIRE (Multi-Object Spectrometer for Infra-Red Exploration) and has been installed in the Keck I Telescope at the W.M. Keck Observatory atop Mauna Kea in Hawaii.

MOSFIRE gathers light in infrared wavelengths - invisible to the human eye - allowing it to penetrate cosmic dust and see distant objects whose light has been stretched or "redshifted" to the infrared by the expansion of the universe.

"The instrument was designed to study the most distant, faintest galaxies," said UCLA physics and astronomy professor Ian S. McLean, project leader on MOSFIRE and director of UCLA's Infrared Laboratory for Astrophysics.

"When we look at the most distant galaxies, we see them not as they are now but as they were when the light left them that is just now arriving here. Some of the galaxies that we are studying were formed some 10 billion years ago - only a few billion years after the Big Bang. We are looking back in time to the era of the formation of some of the very first galaxies, which are small and very faint. That is an era that we need to study if we are going to understand the large-scale structure of the universe."

With MOSFIRE, it will now become much easier to identify faint galaxies, "families of galaxies" and merging galaxies. The instrument also will enable detailed observations of planets orbiting nearby stars, star formation within our own galaxy, the distribution of dark matter in the universe and much more.

"We would like to study the environment of those early galaxies," said McLean, who built the instrument with colleagues from UCLA, the California Institute of Technology and UC Santa Cruz, along with industrial sub-contractors. "Sometimes there are large clusters with thousands of galaxies, sometimes small clusters. Often, black holes formed in the centers of galaxies."

Light collected by the Keck I Telescope was fed into MOSFIRE for the first time on April 4, producing an astronomical image. Astronomers are expected to start using MOSFIRE by September, following testing and evaluation in May and June.

MOSFIRE allows astronomers to take an infrared image of a field and to study 46 galaxies simultaneously, providing the infrared spectrum for each galaxy. Currently, it can take three hours or longer to obtain a good spectrum of just one galaxy, McLean noted.

McLean built the world's first infrared camera for wide use by astronomers in 1986 and since then has built eight increasingly sophisticated infrared cameras and spectrometers - which split light into its component colors - as well as helping on a few others.

McLean and Charles Steidel, the Lee A. DuBridge Professor of Astronomy at the California Institute of Technology, led the project to build MOSFIRE from scratch over seven years. Harland Epps, a UC Santa Cruz professor of astronomy and astrophysics, designed the optics for the instrument.

A team of nearly two dozen people helped, including Kristin Kulas and Gregory Mace, UCLA graduate students in physics and astronomy who work in McLean's laboratory; Keith Matthews, an instrument designer from Caltech; and Sean Adkins, an engineer who is the instrument program manager for the Keck Observatory in Hawaii.

Most of the mechanical parts for MOSFIRE were built at UCLA and Caltech. The slit unit that enables 46 objects to be isolated was manufactured in Switzerland. The computer programming was led by UCLA.

"My father, who was an engineer, called me an astronomer by inclination, a physicist by training and an engineer by default," McLean said. "I'm an applied physicist and an astronomer."

MOSFIRE cost $14 million and likely would have cost at least twice as much if the scientists had not built it themselves, McLean estimates.

MOSFIRE was federally funded by the National Science Foundation (through the Telescope System Instrumentation program), and by Gordon and Betty Moore. Gordon Moore is co-founder, former chairman and chief executive officer, and chairman emeritus of Intel Corp.

"He is a wonderful man with a penetrating intellect," McLean said of Moore. "We are deeply indebted to him and hope to be able to show him MOSFIRE this summer."

"We had an outstanding team," he added, "with four institutions involved and many industrial partners. It was a fantastic team effort."

In the late 1990s, McLean delivered an infrared spectrometer called NIRSPEC to the Keck Observatory in Hawaii, which housed the world's largest optical and infrared telescope at the time and which contains what had been the most powerful infrared spectrometer in the world. NIRSPEC is still on the Keck II Telescope.

While NIRSPEC's camera has one megapixel, MOSFIRE has four megapixels. MOSFIRE's detectors are approximately five times more sensitive than those on NIRSPEC and about 100 times more sensitive than those from McLean's 1986 infrared camera. In addition, the digital imaging devices available today are far superior to those of 15 years ago. The result is that MOSFIRE is much more sensitive to faint objects.

Discoveries made with NIRSPEC include the detection of water on comets, insights into the stars orbiting the enormous black hole at the center of the Milky Way galaxy, and the discovery of the chemical composition of brown dwarfs.

ESA SRON JAXA Astro-H: A New space telescope to explore the violent Universe

European astronomers will be able to explore the universe with a powerful new Japanese space telescope thanks to an agreement recently signed.

Officials from the European Space Agency (ESA) and the Japanese Aerospace Exploration Agency (JAXA) will cooperate in building and operating a satellite called Astro-H.

The orbiting observatory will watch the heavens with X-ray eyes, the latest in a number of space telescopes that can view this part of the spectrum beyond that of visible light. X-rays are emitted by extremely hot events at temperatures ranging from several million to several hundred million degrees Celsius.

Watching them will allow space scientists to observe some of the most extreme phenomena in the Universe including supernova explosions, neutron stars, black holes and the centres of active galaxies.

It will also help them to probe the large-scale structure of the Universe, including clusters of galaxies, and discover how it has evolved over billions of years. It will also help show how matter behaves in extreme gravitational fields.

JAXA’s Dr Tadayuki Takahashi, who invented the technology behind the camera, said: "We are aiming to quickly turn this technology to practical use."

The deal to work together on this exciting mission was signed last month by Professor Alvaro Giménez Cañete, ESA Director of Science and Robotic Exploration, and Dr Junjiro Onoda, Director General of the Japanese Institute of Space and Astronautical Science (ISAS).

ESA will provide JAXA with hardware components and support for operations and users. In return, astronomers at institutions in ESA countries will be granted observing time on the Astro-H mission.

NASA's Goddard Spaceflight Center is also contributing instrumentation to Astro-H, formerly known as NeXT, in collaboration with the University of Wisconsin.

The telescope is due to be launched in 2014 from the Tanegashima Space Centre in Southern Japan and will be placed in low-Eath orbit, which is high enough to be clear of the atmosphere which absorbs X-rays and makes them unobservable on the ground.

Astro-H will carry an array of spectrometers and imagers. But it also offers a prime example of how space science can have direct benefits to life back on Earth.

The spacecraft is being equipped with a gamma-ray detector that will observe the dying gasps of stars that go supernova.

The precision that this instrument is capable of will also be used on the ground to help Japan clean up contamination left by the Fukushima disaster after the massive earthquake in 2011.

Square Kilometre ARRAY (SKA): Astron and IBM to Build Low-Power Exascale Supercomputer

IBM and Astron, the Netherlands Institute for Radio Astronomy, have collaborated to research on exascale computer systems that will help explore the origins of the universe.

The low-power exascale computer systems are targeted for the international Square Kilometre Array (SKA), an international project by Astron to build the world's largest and most sensitive radio telescope.

The supercomputer will collect data from the Square Kilometre Array (SKA), which requires processors that are a million times faster than today's fastest computers.

The supercomputer will reportedly be faster than the current world's fastest supercomputer, the K, that has 700,000 processor cores and a peak performance of 10 petaflops (thousand trillion floating point operations per second) - an exascale computer would be 100 times faster than that.

The initial 32.9 million euro project named Dome is a five-year collaboration with Astron and upon completion of building the telescope by 2024, it will be used to explore evolving galaxies, dark matter and even the very origins of the universe - dating back more than 13 billion years.

Ton Engbersen, IBM Research - Zurich explained: "If you take the current global daily Internet traffic and multiply it by two**, you are in the range of the data set that the Square Kilometre Array radio telescope will be collecting every day."

"This is Big Data Analytics to the extreme. With Dome we will embark on one of the most data intensive science projects ever planned, which will eventually have much broader applications beyond radio astronomy research," he added.

Scientists at Astron and IBM will also investigate the advanced accelerators and 3D stacked chips for more energy-efficient computing. They will also research on technologies to optimize large data transfers, as well as high-performance storage systems.

"Large research infrastructures like the SKA require extremely powerful computer systems to process all the data. The only acceptable way to build and operate these systems is to dramatically reduce their power consumption," said Marco de Vos, Managing Director of Astron.

"Dome gives us unique opportunities to try out new approaches in Green Supercomputing. This will be beneficial for society at large as well," he added.

Scientists from both IBM and Astron will work at the newly established Astron & IBM Center for Exascale Technology in Drenthe, the Netherlands. The construction of the super telescope is expected to begin in 2017.

STFC: SCUBA-2 reveals wild youth of the Universe

A team of astronomers from the UK, Canada and the Netherlands has begun a revolutionary new study of cosmic star-formation history, looking back in time to when the Universe was still in its lively and somewhat unruly youth.

The consortium, co-led by University of Edinburgh astrophysicist Professor James Dunlop, is using SCUBA-2, the most powerful camera ever developed for observing light at ‘sub-mm’ wavelengths (light that has a wavelength 1000 times longer than we can see with our eyes).

Prof. Dunlop presented the first results from the survey at the UK National Astronomy Meeting on 27 March 2012.

The development of SCUBA-2 was led by STFC’s UK Astronomy Technology Centre in Edinburgh and the revolutionary camera was unveiled in December 2011 (link opens in a new window).

It is mounted on the world's largest sub-mm telescope, the 15-metre James Clerk Maxwell Telescope in Hawaii.

The new project, named the SCUBA-2 Cosmology Legacy Survey, will run for three years and will use the camera to provide the clearest view to date of dust-enshrouded star-forming galaxies.

These objects are so remote that the light we detect left them billions of years ago, so we see them as they looked in the distant past.

With SCUBA-2 astronomers are able to study objects that existed as far back as 13 billion years ago, within the first billion years after the Big Bang.

Because stars form inside clouds of gas and dust, much of the ultraviolet light from young galaxies is absorbed by this cosmic dust which is then heated to a few tens of degrees above absolute zero (-273 degrees Celsius).

The ‘warmed’ (but still rather ‘cool’) dust then emits the absorbed energy at far-infrared wavelengths, which is then further redshifted to longer sub-mm wavelengths en-route to the Earth by the expansion of the Universe.

The first image presented here is made using the SCUBA-2 camera at a wavelength of 450 microns.
(Credit: Jim Dunlop)

Detecting such emission is a challenge, both because Earth-based telescopes are warm and hence glow at sub-mm wavelengths and because water vapour in the atmosphere both absorbs and emits light in this waveband.

To get around the problems of the atmosphere, the latest sub-mm surveys have recently been conducted from space, using the Herschel Space Observatory.

However, the relatively small size (3.5-metre diameter) of Herschel’s telescope means that the images it produces cover large areas but are rather fuzzy.

The James Clerk Maxwell Telescope primary mirror is 20 times larger in area and can provide a much sharper view of the sub-mm sky.

Prof. Dunlop is delighted by these first deep SCUBA-2 images and looking forward to more results over the next few years: “Edinburgh scientists and engineers worked hard to construct this revolutionary new instrument and, together with our colleagues in Canada and the Netherlands, we’re now seeing the fruits of our efforts.

With SCUBA-2 we can study the most violently star-forming galaxies in the young Universe, and slowly but surely start to understand how the primitive cosmos evolved into the Universe we live in today.”

Mysterious Dark Energy: What Part in Early Universe

Light from distant galaxies is distorted by foreground matter. 

This so-called weak lensing can be used to characterize dark energy.

CREDIT: S. Colombi (IAP), CFHT Team

Scientists trying to understand dark energy, one of the weirdest things in the universe, have made a step forward in determining how much of it could have existed shortly after the Big Bang.

Dark energy is the mysterious force scientists think is responsible for pulling space apart at the seams, causing the expansion of the universe to accelerate. No one knows what dark energy is, and it hasn't been detected directly.

In the new study, researchers used the South Pole Telescope in Antarctica to observe the cosmic microwave background, the pervasive light left over from the Big Bang that is believed to have kick-started the universe. This radiation holds a record of many properties of the early universe, allowing scientists to deduce the maximum amount of dark energy that could have been present at the time.

Based on their measurements, the researchers found that dark energy could not have accounted for more than 1.8 percent of the total density of the universe. By contrast, dark energy dominates space today, accounting for about 74 percent of all the matter and energy in the universe.

Subaru Telescope Detects Most Distant and Ancient Supernovae in the Young Universe

A team of Japanese, Israeli, and U.S. astronomers used the Subaru Telescope to assemble the largest sample ever found of the most distant exploding stars called supernovae, which emitted their light about ten billion years ago, long before the Earth was formed.

The researchers used this sample of ancient supernovae to determine how frequently such explosions of stars occurred in the young universe.

Supernovae have substantial importance in astrophysics. They are nature's element factories: essentially all of the elements in the periodic table that are heavier than oxygen were formed through nuclear reactions immediately preceding and during these colossal explosions.

The explosions fling these elements into interstellar space, where they serve as raw materials for new generations of stars and planets.

Thus, the atoms in our bodies, like the calcium atoms in our bones or the iron atoms in our blood, were created in supernovae.

By tracking the frequency and types of supernova explosions back through cosmic time, astronomers can reconstruct the universe's history of element creation, from the plain mix of hydrogen and helium that existed for the first billion years or so after the Big Bang, up to the elemental richness we see today.

However, looking back in time requires looking out to great distances, which means that even these bright explosions are exceedingly faint and difficult to spot.

To overcome this obstacle, the team took advantage of a combination of the Subaru Telescope's assets: the huge light-collecting power of its large 8.2 meter primary mirror; the sharpness of its images, and the wide field of view of its prime focus camera (Suprime-Cam).

On four separate occasions, they pointed the telescope toward one single field called the Subaru Deep Field, which spans an area of the sky similar to that covered by the full moon and had previously been studied in great detail by Subaru scientists.

By "staring" with the telescope at this single field, they let the faint light from the most distant galaxies and supernovae accumulate over several nights at a time, thus forming a very long and deep exposure of the field.

Read more at the Subaru Telescope portal

SPINSTARS: the first polluters of the Universe

From the analysis of the chemical composition of some of the oldest stars in our Galaxy, an international team of astronomers led by Cristina Chiappini from the Leibniz-Institut für Astrophysik Potsdam (AIP) and the Instituto Nazionale di Astrofisica (INAF) presents new clues on the nature of the first stellar generations in our Universe.

“We think that the first generations of massive stars were very fast rotators – that’s why we called them spinstars”, explains Chiappini.

Their findings will be published in a Nature article on April 28, 2011.

Massive stars live fast and furious, and hence the first generations of massive stars in the Universe are already dead.

However, their chemical imprints, like fingerprints, can still be found today in the oldest stars in our Galaxy. These fossil records are thus the witnesses of the nature of the first stellar generations to pollute our Universe.

“It is like if we tried to reveal the character of a cook from the taste of his dishes”, says Prof. Georges Meynet, from the Geneva University.

How were these first stars? Were they different from the stars we observe today?

Soon after the Big Bang, the composition of the Universe was much simpler than at present as it was made of essentially only hydrogen and helium.

The chemical enrichment of the Universe with other elements had to wait around 300 million years until the fireworks started with the death of the first generations of massive stars, polluting the primordial gas with new chemical elements, which were later incorporated in the next generations of stars.

Using data from ESO’s Very Large Telescope (VLT), the astronomers reanalyzed spectra of a group of very old stars in the Galactic Bulge.

These stars are so old that only very massive, short-living stars with masses larger than around ten times the mass of our Sun should have had time to die and to pollute the gas from which these fossil records then formed.

As expected, the chemical composition of the observed stars showed elements typical for enrichment by massive stars.

However, the new analysis unexpectedly also revealed elements usually thought to be produced only by stars of smaller masses. Fast-rotating massive stars on the other hand would succeed in manufacturing these elements themselves.

“Alternative scenarios cannot yet be discarded - but - we show that if the first generations of massive stars were spinstars, this would offer a very elegant explanation to this puzzle!”, says Cristina Chiappini. Team member Urs Frischknecht, a PhD student at the Basel University, is already working on extending the stellar simulations in order to further test the proposed scenario.

The impact of having had an early generation of spinstars in the Universe is manifold. Fast rotation also affects other properties of a star, such as its colour, its lifetime and its luminosity. 

Spinstars would therefore also have strongly influenced the properties and appearance of the first galaxies which were formed in the Universe.

The existence of spinstars is now also supported by recent hydrodynamic simulations of the formation of the first stars of the universe by an independent research group.

Further information:

• Original publication: Chiappini et al., Imprints of fast-rotating massive stars in the Galactic Bulge, to be published in Nature, 2011. (DOI: 10.1038/nature10000, publication date: April 28, 2011)

• Leibniz-Institut für Astrophysik Potsdam (AIP) - www.aip.de

NASA Hubble Space Telescope - The Universe's Most Ancient Object

The farthest and one of the very earliest galaxies ever seen in the universe appears as a faint red blob in this ultra-deep–field exposure taken with NASA's Hubble Space Telescope.

This is the deepest infrared image taken of the universe. Based on the object's color, astronomers believe it is 13.2 billion light-years away.

The most distant objects in the universe appear extremely red because their light is stretched to longer, redder wavelengths by the expansion of the universe.

This object is at an extremely faint magnitude of 29, which is 500 million times fainter that the faintest stars seen by the human eye.

The dim object is a compact galaxy of blue stars that existed 480 million years after the Big Bang, only four percent of the universe's current age. It is tiny and considered a building block of today's giant galaxies. Over one hundred such mini-galaxies would be needed to make up our Milky Way galaxy.

The Hubble Ultra Deep Field infrared exposures were taken in 2009 and 2010, and required a total of 111 orbits or 8 days of observing. The new Wide Field Camera 3 has the sharpness and near-infrared light sensitivity that matches the Advanced Camera for Surveys' optical images and allows for such a faint object to be selected from the thousands of other galaxies in the incredibly deep images of the Hubble Ultra Deep Field.

Credit: NASA, ESA, G. Illingworth (University of California, Santa Cruz), R. Bouwens (University of California, Santa Cruz and Leiden University), and the HUDF09 Team

Our Universe is one of many

Some researchers think concentric ring patterns in measurements of the cosmic microwave background are evidence of a universe that existed before our own was born in the Big Bang. 

Credit: Roger Penrose and Vahe Gurzadyan

The evidence in question is said to lie in the haze of microwaves permeating the cosmos that was left over after the Big Bang.

This light, and patterns within it, has granted scientists a picture of the earliest years of the universe.

However, a little over a month ago, a pair of physicists said they found something potentially even more extraordinary in this radiation — giant rings they said could be evidence of a universe that existed before the Big Bang roughly 13.7 billion years ago.

The cosmic microwave background is normally slightly blotchy, showing variations in hot and cold that apparently originate from microscopic fluctuations in the very earliest moments after the Big Bang. Recently, a pair of researchers claimed to have found concentric ring patterns where this radiation is less patchy than normal.

So what are these circles within circles? 

They might be nothing less than the aftermath of collisions of supermassive black holes in a past universe, akin to ripples in a pond, according to calculations from mathematical physicist Roger Penrose at the University of Oxford in England and physicist Vahe Gurzadyan at Yerevan State University in Armenia that appeared online Nov. 16.