Tag Archives: Hubble telescope

Comet NEOWISE Comes into Focus for a Close-up

Time is running out to catch a glimpse of the comet NEOWISE. The comet — the brightest object to grace the skies over the Northern Hemisphere in 25 years — will soon disappear from view. At least as far as the naked eye is concerned. Fortunately, the Hubble Space Telescope is on hand to capture stunning images of the comet — discovered on March 27th by NASA’s Wide-field Infrared Survey Explorer (WISE) space telescope during its mission to search for near-Earth objects. 

Hubble Captures a stunning close-up Comet NEOWISE (NASA, ESA, Q. Zhang (California Institute of Technology), A. Pagan (STScI))
Hubble Captures a stunning close-up Comet NEOWISE (NASA, ESA, Q. Zhang (California Institute of Technology), A. Pagan (STScI))

The image taken by Hubble on 8th August — which represents the closest ever taken of the comet since it first lit up the sky — shows NEOWISE as it sweeps past the Sun. This is the first time that astronomers have managed to capture such a bright object as it passes our star.

Hubble snapped the object as it rapidly makes its way out of the solar system, with it not scheduled to return for 6,800 years. The comet caused a stir amongst amateur star watchers and the general public as it was visible with the naked eye under the right conditions.

“Nothing captures the imagination better than actually seeing its tails stretching into the sky in person,” Qicheng Zhang,  a graduate student studying planetary science at Caltech, Pasadena, CA, who has been heavily involved in the study of NEOWISE. “The comet last came around about 4,500 years ago. This was around when the Egyptian pyramids were being built.”

“My research area covers comets and their evolution under solar heating,” Zhang explains to ZME Science. “I also like to keep track of potentially bright comets to actually see in the sky, which included this particular comet.”

Colour image of the comet taken by Hubble on 8 August 2020 within the frame of a ground-based image of the comet that was taken from the Northern Hemisphere on 18 July 2020. (NASA, ESA, Q. Zhang (California Institute of Technology), A. Pagan (STScI), and Z. Levay)
Colour image of the comet taken by Hubble on 8 August 2020 within the frame of a ground-based image of the comet that was taken from the Northern Hemisphere on 18 July 2020. (NASA, ESA, Q. Zhang (California Institute of Technology), A. Pagan (STScI), and Z. Levay)

The image shows NEOWISE’s halo of glowing gas and dust illuminated by light from the Sun surrounding the icy nucleus of the comet, too small at little more than 4.8km across to be fully resolved by the telescope. In contrast, the dust halo that surrounds the comet’s heart is too large to be fully resolved by the space telescope, with its diameter measuring an estimated 18,000 km.

Zhang points out that as NEOWISE moves past the Sun, there is a chance we could still glimpse its icy core: “As the comet recedes from the Sun, the dust with clear and reveal the solid nucleus currently buried within, providing an opportunity to directly observe the source of all the activity that made the comet impressive last month.”

Let’s Stick Together: Why NEOWISE Survived and ATLAS Didn’t

Previous attempts to capture other bright comets as they pass the Sun have failed because these objects have disintegrated as they passed too close to the star. This break-up is driven by both the incredible heat of the Sun causing the icy heart of the comets to fragment, and the powerful gravitational influence of our star further pulling the comets apart. 

The most striking example of this came shortly after the discovery of NEOWISE, with the observation of the fragmentation of the comet ATLAS in April this year. The collapse of this comet — believed at the time to offer our best look at such an icy body — in 30 separate pieces was also caught by Hubble. 

ATLAS feels the heat. The comet, discovered in December 2019 breaks up under the intense heat and gravitational influence of the Sun ( NASA/ ESA/ STScI/ D. Jewitt (UCLA))
ATLAS feels the heat. The comet, discovered in December 2019 breaks up under the intense heat and gravitational influence of the Sun ( NASA/ ESA/ STScI/ D. Jewitt (UCLA))

Unlike comet ATLAS, itself only discovered in December 2019, comet NEOWISE somehow survived its close passage to the Sun–with its solid, icy nucleus able to withstand the blistering heat of the star– enabling Hubble to capture the comet in an intact state.

As the latest image of NEOWISE shows, however, it is not going to escape its encounter with the Sun completely unscathed. Jets can clearly be seen blasting out in opposite directions from the poles of the comet’s icy nucleus. These jets represent material being sublimated–turning straight from a solid to a gas skipping a liquid stage–beneath the surface of the comet. This ultimately results in cones of gas and dust erupting from the comet, broadening out as the move away from the main body, forming an almost fan-like shape.

This animation composed of three Hubble images of NEOWISE shows clearly jets of sublimated material erupting from the comet forming fan-like shapes. (NASA, ESA, Q. Zhang (California Institute of Technology), A. Pagan (STScI), and M. Kornmesser))

Far from being just a stunning image of a comet as it passes through the inner solar system, the Hubble images stand to teach astronomers much about NEOWISE and about comets in general.

“It’s a fairly large comet that approached closer to the Sun than the vast majority of comets of its size do,” Zhangs says. “These factors contributed to its high brightness and also made it a good candidate to see how solar heating alters comets, as the effects are theoretically amplified by its close approach to the Sun.

“That information is useful for interpreting observed characteristics of other comets that don’t approach as close to the Sun, and thus where the changes are more gradual and might not be directly observable.”

In particular, the colour of the comet’s dust halo, and the way it changes as NEOWISE moves away from the Sun, gives researchers a hint as to the effect of heat on such materials. This could, in-turn, help better determine the properties of the dust and gas that form what is known as the ‘coma’ around a comet.

“We took images to show the colour and polarization of the dust released by the comet, to get a sense of what it looks like before it’s broken down by sunlight,” says Zhang. “That analysis is ongoing–and will take a while to do properly–but as the published images show, we’ve caught at least a couple of jets carrying dust out from the rotating nucleus.”

The information contained in the Hubble data will become clearer as researchers delve deeper into it. But, the investigation of NEOWISE’s cometary counterparts will benefit from future telescope technological breakthroughs. This will include spotting comets much more quickly and thus, further out from the Sun.

“When this comet was discovered by the NEOWISE mission, it was only 3 months from its close approach to the Sun and had already begun ramping up activity,” Zhang says. “More sensitive surveys, like the upcoming Legacy Survey of Space and Time (LSST) at the Rubin Observatory, will allow us to find such comets much earlier before they become active, enabling us to track them throughout their apparition from beginning to end.

“This will facilitate a more precise comparison of what changes the comets undergo during their solar encounter.”

The next step in Zhang’s research, however, will be comparing the qualities of comet NEOWISE to other such objects, particularly a recent interstellar visitor to our solar system: “This is one of three comets I have observed or have planned to observe in this manner, the others being the interstellar comet 2I/Borisov and the distant solar system comet C/2017 K2 (PANSTARRS),” the researcher concludes. “My team of collaborators and I will be evaluating all three comets to see how their differences in present location and formation/dynamical history translate into differences in physical properties.”

A look back at Hubble’s history in honor of its 30th anniversary

“Liftoff of the space shuttle Discovery, with the Hubble Space Telescope, our window on the universe,” were the words uttered by George Diller as STS-31 lifted off into a partly-cloudy Florida sky. That day — April 24, 1990 – was one, indeed, that would shape how we saw the unending expanse of space. The cargo aboard Discovery, 30 years ago, would end up becoming the most prolific space telescope in history and would change not only how we thought about the universe, but the creation of it itself.

Hubble Space Telescope was taken on the fifth servicing mission to the observatory in 2009. (Image: NASA)

The United States space program was still reeling from the Challenger explosion four years prior, and the launch of Hubble was not only a chance to learn more than ever about the universe, but a chance for NASA to remake its image with the public as well.

However, the story of Hubble started much earlier than that.

The road to Hubble

From the dawn of humankind to a mere 400 years ago, all that we knew about our universe came through observations with the naked eye. When Galileo turned his telescope toward the heavens in 1610, the world was in for an awakening.

Saturn, we learned, had rings. Jupiter had moons. That nebulous patch across the center of the sky called the Milky Way was not a cloud, but a collection of countless stars. Within but a few years, our notion of the natural world would be forever changed. A scientific and societal revolution quickly ensued.

In the centuries that followed, telescopes grew in size and complexity and, of course, power. They were placed on mountains far from city lights and as far above the haze of the atmosphere as possible. Edwin Hubble, for whom the Hubble Telescope is named, used the largest telescope of his day in the 1920s at the Mt. Wilson Observatory near Pasadena, California, to discover galaxies much further than our own.

During the 1970s, NASA and the European Space Agency (ESA) began planning for a space telescope that could transcend the blurring effects of the atmosphere and take clearer images of the Universe than ever before. The Hubble telescope was the first major optical telescope to be placed in space, the ultimate mountaintop. Without the atmosphere to hinder its observations, and far removed from rain clouds and light pollution, Hubble has an unobstructed view of the universe.

“Hubble is really a time machine,” said Larry Dunham, Hubble’s chief systems engineer at NASA’s Goddard Space Flight Center, in an interview. “We’re looking at data from light years in the past. Hubble is giving us the opportunity to look back in time to see how things were formed.”

Like every good love story, this one has its ups and downs with Hubble being the knot that ties the marriage of human curiosity and the science with satisfies it. Also, like a good marriage – and unlike most satellites – it gets better and stronger with age. Fifteen years after its expected lifespan, she has still not given up the ghost and has some of her most important discoveries just ahead.

The most marvelous part of the telescope, of course, is the 94.5-inch (2.4-meter-wide) mirror. As Eric Chaisson, an American astrophysicist and author wrote in his book The Hubble Wars, “While not the largest ever built, Hubble’s mirror is assuredly the cleanest and most finely polished mirror of its size. If Hubble’s mirror were scaled up to equal the width of the North American continent, the highest hill or lowest valley would be a mere few inches from the average surface.”

Up to a slow start

The mirror was also the headline when Hubble’s debut picture was snapped. Four weeks after leaving Discovery’s payload bay, the telescope’s initial offering to the public was that of a somewhat blurry photo of binary star HD96755, about 1,300 light-years away. A spherical aberration caused by a manufacturing error was causing the telescope to bring in only 10 to 15 percent of a star’s light into focus, as opposed to the 70 percent it should be gathering. Picture after picture revealed in no clearer images. Engineers eventually found that the shape of the concave mirror, moving from the center to the outer edge, was too shallow by up to two microns — 1/50 the width of a human hair.

Despite the flawed lens, Hubble was still able to take better pictures than any Earth-bound telescope (Image: NASA)

However slight, the error turned what was the most heralded telescope in NASA’s history into the laughingstock of the world. In fact, it wouldn’t be until December of 1993, three and a half years later, that the crew of Columbia would come to the rescue with a set of corrective optics to restore Hubble’s vision.

“The mirror flaw was a disappointment,” said Dunham. “It was really a disappointment that it showed up in the news. Even with the spherical aberration, the images we were getting were still better than anything we had ever had in the past.”

Replacing the mirror was not practical, so the best solution was to build replacement instruments that fixed the flaw much the same way a pair of glasses correct the vision of someone who is near-sighted. The corrective optics and new instruments were built and installed on Hubble by spacewalking astronauts during the STS-61 mission in 1993. The Corrective Optics Space Telescope Axial Replacement (COSTAR) instrument, which was about the size of a telephone booth, placed into Hubble five pairs of corrective mirrors that countered the effects of the flaw.

Kathryn Thornton replacing the solar arrays of the Hubble space telescope during the STS-61 mission (Image: NASA)

Once the mirror had a new set of spectacles, she now had the ability to look farther into universe than anything humans had ever produced. When astronomers pointed her to before had been an empty patch of sky in Ursa Major in 1995, they captured an image of over 3,000 galaxies too distant to be detected by other telescopes. (This was later called the Hubble Deep Field). Some of the galaxies Hubble found were so young, they had not yet begun serious star formation. Other deep field findings in the same area were performed, peering deeper into space each time. These were called the Hubble Ultra-Deep Field (released in 2004) and the Hubble eXtreme Deep Field (released in 2012). 

Besides the extraordinary finds, Hubble was famous for another reason. Unlike other satellites, Hubble was made into a better machine as time wore on. Each service mission would renew and improve her capabilities.

“With the servicing missions have allowed us to upgrade both the science instruments as well as the spacecraft hardware,” said Dunham. “Actually, it took us so long to get it up there initially (due to the delay after the Challenger explosion), that by the time we finally got Hubble up, a lot of its hardware was already obsolete. The recorders we launched with were tape, and now we have upgraded those to digital. The original computer we had was six-point binary assembly coding with a huge 32k of memory. Now we’ve got a 46 computer up there that has megabytes.”

Picture of the core of the galaxy M100 before and after the first servicing mission (Image: NASA)

In February 1997 the second servicing mission took place, resulting in the replacement of degrading spacecraft components, and the installation of new instruments such as the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). STIS separated the light the telescope took in, and “dissected” it so that the composition, temperature, motion and other properties could be analyzed. With NICMOS, astronomers could see the first clear views of the universe at near-infrared wavelengths. 

On November 13, 1999, the fourth of six gyroscopes failed, and the telescope temporarily closed its eyes on the universe. Traveling at speeds of five miles per second, the gyros measure the spacecraft’s rate of motion and help point Hubble toward its observation target. Unable to conduct science without three working gyros, Hubble entered a state of safe mode dormancy. Essentially, Hubble took a nap while it waited for help. 

The third servicing mission was originally conceived as one of maintenance, but when the fourth gyro failed, NASA divided the work into two missions — and in the process, upheld the time-honored tradition of governments just making things more confusing by instead of calling them a third and fourth service mission, called them Servicing Mission 3A (SM3A) and Servicing Mission 3B (SM3B).

SM3A flew in December 1999 and the second in March 2002. During SM3A astronauts replaced all six gyroscopes with new ones, and installed a faster, more powerful main computer, a next-generation solid-state data recorder, a new transmitter, new insulation and other equipment. During SM3B, astronauts installed a new science instrument called the Advanced Camera for Surveys (ACS). ACS sees in wavelengths ranging from visible to far-ultraviolet, and can produce 10 times the science results in the same amount of time than the camera it replaced, the Faint Object Camera (FOC). 

Servicing Mission 4 (SM4), the fifth – and last — visit to Hubble, occurred in May 2009. Astronauts installed two new scientific instruments: the Cosmic Origins Spectrograph (COS) and Wide Field Camera 3 (WFC3). Two failed instruments, the Space Telescope Imaging Spectrograph (STIS) and the Advanced Camera for Surveys (ACS), were brought back to life by the first-ever on-orbit instrument repairs. In order to prolong Hubble’s life, other components were replaced including new batteries, new gyroscopes and a new science computer. In addition, a device was attached to the base of the telescope to facilitate de-orbiting when the telescope is eventually decommissioned. 

As things are now, that decommissioning date looks like it will be long in the future. Originally given a shelf life of 15 years, Dunham says that reentry of the satellite probably won’t occur until 2046, a 56-year span since it lifted off aboard Discovery. To put that in perspective, that is only five years less than when the telescope’s namesake reached his expiration date.

With the launch of the highly touted James Webb Telescope approaching nearer, the Hubble’s capabilities should only increase.“There are a lot of observations that people want to do in parallel with the Webb,” said Dunham. “The two spacecraft look at different light spectrums, so you can look at something with the Webb and get once sense of the object you’re looking at and then look at it with the Hubble and get another sense. Together you can produce some amazing science.”

Maybe it was appropriate that Discovery was the ship that took Hubble into orbit. The opportunities and discoveries we have made are more than the number of coins it took to produce it.

Famed poet Walt Whitman might have pegged it when he wrote:

“O to realize space!
The plenteous of all, that there are no bounds,
To emerge and be of the sky, of the sun and moon and flying clouds,
as one with them.”

NASA tries to fix Hubble problem by switching it off and on again

A solution that works far too often on Earth also seems to work off the ground.

Hubble is at it for 30 years — and it’s still going strong. Image: NASA.

You’ve never really used a computer unless you tried fixing something by switching it off and on again. It has an almost mystic quality to it, seeming to magically fix at least half of the common issues. But it doesn’t seem like something you’d try on a space telescope.

Hubble, one of the largest, most versatile, and most useful scientific instruments ever developed by mankind, has been in operation since 1990. Naturally, when you’re working in space for three decades, some things are bound to go wrong. Hubble is no stranger to wear and tear, being subjected to a few interventions over the years.

The most recent problem Hubble had was with one of its gyroscopes — devices that measure how fast the spacecraft is turning, and which essentially allow engineers to know where Hubble is looking at.

[panel style=”panel-default” title=”Gyro” footer=””]Hubble’s gyroscopes feature a wheel that spins at a constant 19,200 revolutions per minute. This wheel is mounted in a sealed cylinder, called a float. The float is suspended in a thick fluid.

Thin wires are immersed in the fluid, and they carry electricity to the motor. Electronics within the gyro detect very small movements of the axis of the wheel and communicate this information to Hubble’s central computer.

These gyros have two modes — high and low. High is used for coarse movements, whereas low is more of a high-precision mode.[/panel]

Hubble’s emblematic images have been a massive boon to astronomy and science in general. Image: NASA.

In an attempt to correct the malfunctioning gyro, the Hubble operations team restarted it — they switched it off for a second and then back on again. The gyroscope was also switched from high to low mode several times to clear any potential blockage in the fluid.

Initially, the data showed no improvement in the gyro’s performance. But after several switches, things started to improve. Hubble executed additional maneuvers to make sure that the gyro remained stable within operational limits as the spacecraft moved, and everything seemed to go along normally.

After additional engineering tests are completed, Hubble will return to its normal scientific activity.

Of course, it’s not as simple as saying that NASA just restarted Hubble and it worked — but it’s a bit funny how such a familiar approach (at least in principle) can work on anything from your old computer to one of the most complex machines ever built.

On the left is Pisces A, 19 million light-years away. On the right we can see Pisces B, which is around 30 million light-years way. Credit: NASA, ESA, and E. Tollerud (STScI)

Two dwarf-galaxies have left the wilderness to join a galactic party

On the left is Pisces A, 19 million light-years away. On the right we can see Pisces B, which is around 30 million light-years way. Credit: NASA, ESA, and E. Tollerud (STScI)

On the left is Pisces A, 19 million light-years away. On the right we can see Pisces B, which is around 30 million light-years way. Credit: NASA, ESA, and E. Tollerud (STScI)

Hubble just spotted two dwarf galaxies leave the galactic wilderness for a much more crowded region, drawn in by gravity. The pair previously inhabited a region of the Universe sparsely populated with galaxies, the 150 million light-years across Local Void. Astronomers say the galaxies are now ready to seriously nurse many new stars as they enter a more welcoming breeding ground rich in gas and dust.

“These Hubble images may be snapshots of what present-day dwarf galaxies may have been like at earlier epochs,” said lead researcher Erik Tollerud of the Space Telescope Science Institute in Baltimore, Maryland. “Studying these and other similar galaxies can provide further clues to dwarf galaxy formation and evolution.”

A dwarf galaxy is a small galaxy composed of about 100 million up to several billion stars. Though impressive, it’s still a trifle even when compared to a medium-sized galaxy like the Milky Way which hosts 200–400 billion stars. But dwarf galaxies, which are extremely faint and hard to detect, are extremely interesting for astronomers.

First of all, they’re the most numerous kind of galaxies in the universe. Secondly, dwarfs are the Milky Way’s closest neighbours allowing high-quality data to be gathered by telescopes. Dwarfs were also the building blocks of larger galaxies which formed billions of years ago — after all, everything started out small. We owe a lot of what we know about how galaxies form to dwarfs.

These recent dwarfs spotted by the Hubble Telescope, Pisces A and B, each contain only about 10 million stars — very sparsely populated even by galactic dwarven standards.

“These galaxies may have spent most of their history in the void,” Tollerud explained. “If this is true, the void environment would have slowed their evolution. Evidence for the galaxies’ void address is that their hydrogen content is somewhat high relative to similar galaxies. In the past, galaxies contained higher concentrations of hydrogen, the fuel needed to make stars. But these galaxies seem to retain that more primitive composition, rather than the enriched composition of contemporary galaxies, due to a less vigorous history of star formation. The galaxies also are quite compact relative to the typical star-forming galaxies in our galactic neighborhood.”

Astronomers found the dwarf pair while surveying hydrogen content in the Milky Way using radio telescopes. Thousands of small blobs packed with dense hydrogen gas were discovered within our galaxy, but some 30 to 50 of these blobs seemed to be located outside of it. Tollerud and colleagues then selected a couple which seemed like worthy candidates for nearby galaxies and asked permission to use Hubble’s Advanced Camera for Surveys to analyse them.

For this purpose, Hubble is particularly well-suited thanks to its sharp vision which can resolve individual stars and reliably estimate a galaxy’s distance. The distance is particularly important for determining brightness, as well as for calculating how far a galaxy is from a void.

The scientists found Pisces A is 19 million light-years away from Earth while Pisces B is roughly 30 million light-years away. Each galaxy has 20 to 30 bright blue stars, signifying they’re still very young — less than 100 million years old. At some point, the galaxies doubled their star formation rate as they closed in a more crowded sector. This star formation rate may slow down if the dwarfs draw too near a much larger galaxy and become satellites.

“The galaxies could even probably stop forming stars altogether, because they will stop getting new gas to make stars,” Tollerud said. “So they will use up their existing gas. But it’s hard to tell right now exactly when that would happen, so it’s a reasonable guess that the star formation will ramp up at least for a while.”

Findings appeared in the Astrophysical Journal.

 

ngc-star-cluster-for-blind

Universe at your fingertips – 3D prints of Hubble photos let the blind ‘see’

NGC 609 is one of the many small galactic star clusters located in the Milky Way in Cassiopia. It shines at magnitude 11.0, is 4 arc minutes in diameter and contains over 100 stars. Photo: Hubble telescope.

NGC 609 is one of the many small galactic star clusters located in the Milky Way in Cassiopia. It shines at magnitude 11.0, is 4 arc minutes in diameter and contains over 100 stars. Photo: Hubble telescope.

Captioned above is one of Hubble‘s most famous and beautiful space photos. The photo features NGC 609 – a magnificent star cluster, which Hubble captured complete with colored gas, dust and a slew of stars of various brightness. Pictures like these remind people of the tremendous gift they have – sight. How can one share and hope to convey a fraction of the stunning beauty one experiences when looking at pictures like NGC 609 to those less fortunate, deprived of sight?

The full valor of visual beauty may never be reproduced to the blind (one can imagine however relaying electrical signals through an EEG directly to the brain, creating an accurate mental picture. this is SciFi at the moment, however), nevertheless some scientists are trying their best. A team of astronomers and computer engineers at the Space Telescope Science Institute in Baltimore, Md have made 3D printed models of NGC 609, specially designed so the blind can have a mental picture of how the star cluster looks like using their sense of touch.

ngc-star-cluster-for-blind

Some 100 volunteers aged 8 to 81 were asked to give feedback, and eventually a rather accurate tactile model was made. Made of plastic, the models includes features like stars, gas and dust differentiated not by color or other visual cues, but through texture. The varying heights of the features correspond to varying levels of brightness.

“We found we were able to create mental models for these people,” astronomer Carol Christian says. “They would say, ‘I can see it, I can see it,’ and then they would describe what they were seeing in their head.”

Still, these model are representations of flat, 2-D images. A fantastic upgrade would be making a 3D spherical model of NGC 609, if the various technical and artistic challenges are overcome.

“Our ultimate goal is for anyone who would like to hold a piece of the universe in their hands, can get the data files that we will process from the Hubble archive, and they can print them at home, at school, or in a library,” Christian says.

Abell 2744, Pandora's Cluster. Photo: : NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team

Hubble goes farther than ever before: images reveal deepest view of the Universe yet

Abell 2744, Pandora's Cluster. Photo: : NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team

Abell 2744, Pandora’s Cluster. Photo: : NASA, ESA, and J. Lotz, M. Mountain, A. Koekemoer, and the HFF Team. Huge resolution photo here.

This year Hubble will embark on one its most ambitious projects yet, as it’s scheduled to glimpse farther away into the Universe than ever before. Six new “deep field” images are slated, and recently astronomers at Hubble have delivered the first to the public. The image reveals extremely faint, tiny galaxies that may be more than 12 billion light-years away, and offer tantalizing clues of things to come in the next parts of the project – findings that could show how the Universe looked like in its infancy and how the cosmos formed in its present form.

“It is the deepest view of the universe ever taken,” says project leader Jennifer Lotz of the Space Telescope Science Institute (STScI) in Baltimore. “We’re seeing things 10 or 20 times fainter than anything we’ve seen before.” Lotz and her colleagues presented the image today here at the 223rd meeting of the American Astronomical Society.

The image is shows the massive galaxy cluster Abell 2744, the deepest ever made of any cluster of galaxies. Some of the faintest and youngest galaxies ever detect in space are shown, after the telescope used 50 hours of light exposure. Some 3,000 ancient galaxies can be found in the cluster – their exact distance from Earth will be determined following observations taken by NASA’s Spitzer and Chandra space telescopes, which see in infrared and x-ray light, respectively.

A deep view

Hubble started its first Deep Field images in 1996, and since then thousands of previously undiscovered galaxies were identified in “blank patches” of space. In the new project, called Hubble “Frontier Fields,” researchers plan on peering farther than ever before, making use of advanced cameras mounted on the space telescope, combined with natural occurring gravitational lenses.

Gravitational lenses naturally magnify views of distant galaxies the lie behind very massive objects, like galaxy clusters. These massive objects cause light to warp and curve, so any object behind them will look brightened and magnified to observers on Earth. It’s a neat trick, one that astronomers are keen to exploit to make the best and deepest images of the Universe.

So far, data is preliminary and starting May this year, Hubble will collect more data on this first field, bringing the photo’s total exposure time to 103 hours, and over the next three years it will examine the other five Frontier Fields, which were chosen at spots where nature’s most powerful gravitational lenses lie.

“We’re really interested in knowing what happened in that first billion years of the universe,” Lotz says. “The thing that Frontier Fields is going to do is look for the galaxies that were basically small enough in those first billion years to turn into our Milky Way Galaxy. We want to know, when did galaxies like the Milky Way first come to be?”

via Scientific American

Hubble space telescope images of the space body taken on 10 September (left) and 23 September 2013 (right). These show P/2013 P5 with six tails, which surround it like the spokes of a cartwheel. While most of the tails became less bright between the observations, tail F significantly increased in brightness. © NASA / HST

Rapidly rotating asteroid blazes with six tails trailing

This oddball cosmic body, called  P/2013 P5, has puzzled astronomers for a while. By mass and orbit, it can only be classed as an asteroid, but the fact that it trails gas or dust would make it a comet. In fact, this weird rock has six tails, which would maybe make it a supercomet! Researchers at the Max Planck Institute for Solar System Research believe they have finally unraveled the mystery, though: P/2013 P5 is rotating so fast under the influence of solar pressure that it constantly loses material into space.

The old classification of asteroids and comets in our solar system goes something like this: asteroids are nothing but rocks whose structure and overall appearance hasn’t changed or morphed for billions of years, apart from the occasional impacts here and there; comets on the other hand are “gas and dust ejectors”, as material at its surface, liked iced water, becomes vaporized releasing dust and gas which forms the iconic trailing tail we all know.

 Hubble space telescope images of the space body taken on 10 September (left) and 23 September 2013 (right). These show P/2013 P5 with six tails, which surround it like the spokes of a cartwheel. While most of the tails became less bright between the observations, tail F significantly increased in brightness.  © NASA / HST

Hubble space telescope images of the space body taken on 10 September (left) and 23 September 2013 (right). These show P/2013 P5 with six tails, which surround it like the spokes of a cartwheel. While most of the tails became less bright between the observations, tail F significantly increased in brightness. © NASA / HST

Over the years, however, scientists have discovered some cosmic bodies that don’t apparently fit any category. A comet in the asteroid belt? Or an asteroid which ejects gas and dust? This becomes even more confusing when you hear some scientists talk about active asteroids or main-belt comets. So, where does this weird P/2013 P5 fit in?

Photos taken this August by Hubble showed that the object had adorned itself with a tail. An impact with another smaller body could have penetrated deep through a maybe exposed a pocket of water to create the trail. But P/2013 P5 hasn’t one, but six tail. The chances of being hit six times is improbable. Also, since P/2013 P5 moves at the inner edge of the asteroid belt – i.e. very close to the Sun for an asteroid – it should no longer contain any ice at all, so Max Plank astronomers looked closer.

Driven by sunlight pressure, it was found that the object moves so fast that it loses mass.  Since it hits the rugged surface at different angles, all in all it can produce a total angular momentum which accelerates its rotation more and more. At some stage, this will cause the centrifugal force at the equator to become stronger than the weak gravitational force of the body, which has a diameter of only 240 metres and is thus quite small; matter is therefore ejected from the surface. So,  P/2013 P5 reputation is saved. It truly is an asteroid, though an oddball one.

To demonstrate these ideas, the Max Plank scientists ran a simulation and succeeded in reconstructing precisely these changes.

“Our computations and the actual observations are in very good agreement,” was the conclusion drawn by Jessica Agarwal, who carried out the computations. “It is particularly encouraging that we were able to achieve good reproduction of the temporal development between the two days of observation.”

The multi-talented asteroid was described in a paper published in the Astrophysical Journal Letters.

These are NASA Hubble Space Telescope natural-color images of four target galaxy clusters that are part of an ambitious new observing program called The Frontier Fields. NASA's Great Observatories are teaming up to look deeper into the universe than ever before. The foreground clusters range in distance from 3 billion to 5 billion light-years from Earth. (c) NASA/ESA

NASA’s great observatories combine to probe deeper in the Universe

These are NASA Hubble Space Telescope natural-color images of four target galaxy clusters that are part of an ambitious new observing program called The Frontier Fields. NASA's Great Observatories are teaming up to look deeper into the universe than ever before.  The foreground clusters range in distance from 3 billion to 5 billion light-years from Earth. (c) NASA/ESA

These are NASA Hubble Space Telescope natural-color images of four target galaxy clusters that are part of an ambitious new observing program called The Frontier Fields. NASA’s Great Observatories are teaming up to look deeper into the universe than ever before. The foreground clusters range in distance from 3 billion to 5 billion light-years from Earth. (c) NASA/ESA

Each of NASA’s Great Observatories – Hubble, Spitzer and Chandra – have been designed to peer through the Universe in a characteristic manner. The telescopes have provided along the years massive amount of astronomical data and have helped scientists make important discoveries. What if you combine each of the telescopes’ strong points to assemble one massive probe capable of seeing farther in the Universe than ever before? That’s exactly what  The Frontier Fields ambitious space program will undertake in the following three years, combining the observational power of all three major NASA telescopes along with natural gravitational lenses to study six massive clusters of galaxies.

“The Frontier Fields program is exactly what NASA’s Great Observatories were designed to do; working together to unravel the mysteries of the universe,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “Each observatory collects images using different wavelengths of light with the result that we get a much deeper understanding of the underlying physics of these celestial objects.”

The program will tackle galaxy clusters that are among the most massive assemblages of matter known. Because of their humongous mass, these galaxy clusters (hundreds to thousands of galaxies bound together by gravity), exert powerful gravitational fields which can be used to brighten and magnify more distant galaxies so they can be observed. This is called gravitational lensing  and because of it  light rays that would have otherwise not reached the observer are bent from their paths and towards the observer.

Pandora’s Cluster. (c) NASA

Pandora’s Cluster. (c) NASA

The first object the astronomers will be directing their view towards is  Abell 2744 or  Pandora’s Cluster. This giant cluster is actually thought to be the result of four distinct galaxy clusters that piled-up over the span of 350 million years.  Studying this cluster, astronomers hope they can discover galaxies that were formed just a few hundred millions years after the Big Bang.

“The idea is to use nature’s natural telescopes in combination with the great observatories to look much deeper than before and find the most distant and faint galaxies we can possibly see,” said Jennifer Lotz, a principal investigator with the Space Telescope Science Institute in Baltimore, Md.

Each Great Observatory will have its role to play. Hubble tells astronomers in which way to direct their view and how many galaxies or stars are born in a system. Spitzer can relay how old these cosmic bodies are. Chanda, using its  X-ray wavelengths instruments, will image the clusters and tell astronomers what their  mass and gravitational lensing power is.

“We want to understand when and how the first stars and galaxies formed in the universe, and each great observatory gives us a different piece of the puzzle,” said Peter Capak, the Spitzer principal investigator for the Frontier Fields program at NASA’s Spitzer Science Center at the California Institute of Technology, Pasadena.

 

This galaxy weighs more than 200 million suns, over half of which is concentrated within a radius of just 80 light years. (c) NASA/CXC/MSU/J.Strader et al, Optical: NASA/STScI

The stars of the densest galaxy discovered thus far are 25 times closer than in Milky Way

This galaxy weighs more than 200 million suns, over half of which is concentrated within a radius of just 80 light years. (c) NASA/CXC/MSU/J.Strader et al, Optical: NASA/STScI

This galaxy weighs more than 200 million suns, over half of which is concentrated within a radius of just 80 light years. (c) NASA/CXC/MSU/J.Strader et al, Optical: NASA/STScI

Using NASA’s Hubble Space Telescope, followed by observations done with NASA’s Chandra X-ray Observatory and ground-based optical telescopes, astronomers have identified what’s considered to be the densest galaxy found so far in the nearby part of the Universe. Classed as an  “ultra-compact dwarf galaxy” and dubbed as M60-UCD1, the density of stars in the galaxy is about 15,000 greater than  that found in Earth’s neighborhood in the Milky Way, meaning that the stars are about 25 times closer.

Subsequent observations made by the W. M. Keck Observatory on the summit of Mauna Kea, Hawaii, found M60-UCD1 to be the most luminous galaxy of its type observed thus far, while being one of the most massive at the time – about 200 million times the mass of the sun. Now for a galaxy, this kind of mass isn’t large by any means but what makes M60-UCD1 unique is that half of its mass is concentrated around a radius a mere 80 light-years across. Furthermore the galaxy is also particularly interesting because it is abundant in heavy elements making it a potentially fertile environment for planets, and maybe even life, to form. Were our sun to be located in such a galaxy, interstellar flight would be much easier.

“Traveling from one star to another would be a lot easier in M60-UCD1 than it is in our galaxy,” said Jay Strader of Michigan State University in Lansing, first author of a new paper describing these results. “But it would still take hundreds of years using present technology.”

For comparison, our closet neighboring star, Alpha Centauri, is located some 4 light-years away. Even so, using currently available technology, it take roughly 80,000 years for a probe to reach it.

Like most galaxies, M60-UCD1 might also have a black hole lurking at its center. Chandra data that revealed a bright X-ray source coming from the galaxy’s center supports this idea. If true, the giant black hole might  weigh 10 million times the mass of the Sun.

Currently, astronomers are trying to establish if galaxies such as M60-UCD1, known as ultra-compact dwarf galaxies, were formed as jam-packed star clusters from the get-go or whether these are actually remnants of larger galaxies who have gotten smaller with time as stars are being ripped away.Large black holes are not found in star clusters, so if the X-ray source is in fact due to a massive black hole, it was likely produced by collisions between the galaxy and one or more nearby galaxies. The mass of the galaxy and the Sun-like abundances of elements also favor the idea that the galaxy is the remnant of a much larger galaxy.

“We think nearly all of the stars have been pulled away from the exterior of what once was a much bigger galaxy,” said co-author Duncan Forbes of Swinburne University in Australia. “This leaves behind just the very dense nucleus of the former galaxy, and an overly massive black hole.”

If this is the case, then M60-UCD1 might have been 50 to 200 times more massive than it is at observation.  The researchers estimate that M60-UCD1 is more than about 10 billion years old. The galaxy is located near a massive elliptical galaxy NGC 4649, also called M60, about 60 million light years from Earth.

The densest galaxy fund thus far was described in a paper recently published in The Astrophysical Journal Letters.

 

Not too long ago, the Ring nebula was thought to be shaped like a sphere. New Hubble observations, coupled with ground imaging, show that the nebula is actually shaped like a bagel. In the image, the deep blue color in the center represents helium; the cyan color of the inner ring is the glow of hydrogen and oxygen; and the reddish color of the outer ring is from nitrogen and sulfur. (c) NASA

“Ring Nebula” imaged in stunning never before seen 3-D detail

Not too long ago, the Ring nebula was thought to be shaped like a sphere. New Hubble observations, coupled with ground imaging, show that the nebula is actually shaped like a bagel. In the image, the deep blue color in the center represents helium; the cyan color of the inner ring is the glow of hydrogen and oxygen; and the reddish color of the outer ring is from nitrogen and sulfur. (c) NASA

Not too long ago, the Ring nebula was thought to be shaped like a sphere. New Hubble observations, coupled with ground imaging, show that the nebula is actually shaped like a barrel. In the image, the deep blue color in the center represents helium; the cyan color of the inner ring is the glow of hydrogen and oxygen; and the reddish color of the outer ring is from nitrogen and sulfur. CLICK ON THE IMAGE FOR A MASSIVE MAGNIFIED VIEW (c) NASA

The “Ring Nebula” is a very popular target for amateur astronomers around the world since its bright glow and highly characteristic shape make it easily identifiable, even to those who have yet to learn even the most basic tricks of the trade. This fantastic cosmic cloud tells the story of a dying star and for years astronomers have been peering it with powerful telescopes, such as Hubble, looking to learn more about it.

New observations from Hubble, courtesy of the telescope’s powerful Wide Field Camera 3 instrument, now show that nebula isn’t shaped like a ring at all, but rather like a doughnut filled with  jelly in its inner rim. The object is tilted toward Earth so that astronomers see the ring face-on, but when imaged in 3-D the nebula’s shape is more sophisticated.

“The nebula is not like a bagel, but rather, it’s like a jelly doughnut, because it’s filled with material in the middle,” study leader C. Robert O’Dell, an astronomer with Vanderbilt University in Nashville, Tenn., said in a statement today.

 The doughnut-shaped feature in the center of the graphic is the main ring. The lobes above and below the ring comprise a football-shaped structure that pierces the ring. Dense knots of gas are embedded along the ring's inner rim. Illustration courtesy of NASA

The doughnut-shaped feature in the center of the graphic is the main ring. The lobes above and below the ring comprise a football-shaped structure that pierces the ring. Dense knots of gas are embedded along the ring’s inner rim. Illustration courtesy of NASA

The Ring nebula is a fantastic example of what happens to a star when it dies and we’ve been lucky enough to be close enough to see this. Located 2,000 light-years away in the Lyra constellation, the nebula formed some 4,000 years ago when a star, several times the mass of the sun, died. After the star burned all its nuclear fuel, it started to expand until it grew into a massive red giant. During this point the star began shedding its outer layers of gas as it collapsed in on itself to become a white dwarf; layers which were then expelled across trillions of miles by the the solar wind generated by the dying star. By studying the nebula, researchers hope to learn more about how Earth’s sun, which is a middle-age star, will die in 6 billion years.

“When the sun becomes a white dwarf, it will heat more slowly after it ejects its outer gaseous layers,” O’Dell said. “The material will be farther away once it becomes hot enough to illuminate the gas. This larger distance means the sun’s nebula will be fainter because it is more extended.”

Check out the video below for a fly-around and zoom on the Ring nebula for a better perspective.

double-einstein-ring

Extremely rare double Einstein ring imaged by Hubble

double-einstein-ring

(c) NASA/ESA

Hubble just never ceases to surprise. The latest astronomical find discovered using the ever resourceful space telescope is a never before encountered double ring pattern known as an Einstein ring. This very rare pattern is the result of a peculiar optical alignment in which three galaxies are perfectly aligned with each other, like beads on a string. The occurrence isn’t just a silly optical trick in space – studying it, astronomers can learn more about dark matter and dark energy, and even the curvature of the Universe.

The phenomenon that gave rise to this peculiar observation is known as gravitational lensing, in which the light emitted by a galaxy in the background gets bent by the gravitational pull of a massive galaxy in the foreground. In our case, one could say we have a double gravitational lens on our hands since a third massive galaxy lies in the foreground. When two galaxies are exactly lined up, the light gets twisted in such a fashion that it forms a shape that resembles a circle, called Einstein’s ring. When three of them are perfectly lined up, such as the case, two concentric rings form.

“Such stunning cosmic coincidences reveal so much about nature. Dark matter is not hidden to lensing,” added Leonidas Moustakas of the Jet Propulsion Laboratory in Pasadena, California, USA. “The elegance of this lens is trumped only by the secrets of nature that it reveals.

The odds of such a phenomenon being observable from Earth’s vantage point are so dim, that the discovery can be considered nothing short of jackpot! In fact, the team of astronomers led by Raphael Gavazzi and Tommaso Treu of the University of California, Santa Barbara were extremely lucky to spot it in the first place. SLACS team member Adam Bolton of the University of Hawaii’s Institute for Astronomy in Honolulu first identified the lens in the Sloan Digital Sky Survey (SDSS). “The original signature that led us to this discovery was a mere 500 photons (particles of light) hidden among 500,000 other photons in the SDSS spectrum of the foreground galaxy,” commented Bolton.

The geometry of the two rings allowed the researchers to establish the mass of the middle galaxy precisely to be a value of 1 billion solar masses – a dwarf galaxy. This is actually the first time a dwarf galaxy’s mass was measured at cosmological distance. The comparative radius of the rings could also be used to provide an independent measure of the curvature of space by gravity.

The results were reported at the 211th meeting of the American Astronomical Society in Austin, Texas, USA. A paper has been submitted to The Astrophysical Journal.

[source]

 

NASA and ESA

Farthest supernova discovered by Hubble helps unravel Universe secrets

Astronomers using NASA’s Hubble Space Telescope have come across the farthest supernova of its type found thus far – a type Ia supernova which exploded some 10 billion years ago. The discovery isn’t just about setting milestones, however. Supernovae act as beacons that help astronomers measure the expansion of the Universe, and this latest finding will help deepen our understanding, especially concerning dark energy.

Dubbed UDS10Wil and nicknamed SN Wilson after the former American President Woodrow Wilson, it took 10 billion years for the light of this violent star explosion to reach Earth.

“This new distance record holder opens a window into the early universe, offering important new insights into how these stars explode,” said David O. Jones of Johns Hopkins University in Baltimore, Md., an astronomer and lead author on the paper detailing the discovery. “We can test theories about how reliable these detonations are for understanding the evolution of the universe and its expansion.”

Because of the Universe’s expansion, the distance light needed to reach Earth from the dawn of the supernova doesn’t equal the actual distance SN Wilson is located at this time with respect to our planet. This is why despite SN Wilson is just  four percent more distant than the previous oldest supernova, it’s still 350 million years older than any star explosion.

NASA and ESA

(c) NASA and ESA

The find was made part of ongoing project of the Hubble team, which first began in 2010, tasked with finding  faraway Type Ia supernovae and determining whether they have changed during the 13.8 billion years since the explosive birth of the universe. Since then, the team has uncovered more than 100 supernovae of all types and distances, looking back in time from 2.4 billion years to more than 10 billion years. This wouldn’t had been possible were it not for the extremely sharp  Wide Field Camera 3 instrument aboard Hubble, which peers in near-infrared light for signs of supernovae and verifies their distance with spectroscopy.

[RELATED] New type of supernova discovered – the third

 

A distant yardstick

Because they’re some of the brightest spots in the Universe, supernovae provide accurate and reliable reference points for measuring the expansion of the Universe and better our understanding of dark energy – the driving force that pushes the Universe to expand. Type Ia supernovae are especially useful since they’re the most brightest.

“The Type Ia supernovae give us the most precise yardstick ever built, but we’re not quite sure if it always measures exactly a yard,” said team member Steve Rodney of Johns Hopkins University. “The more we understand these supernovae, the more precise our cosmic yardstick will become.”

Moreover, the discovery of ever distant Type Ia supernovae helps unravel how they form. Currently, scientists are divided in opinions between two formation models.  In one model the explosion is caused by a merger between two white dwarfs. In another model, a white dwarf gradually feeds off its partner, a normal star, and explodes when it accretes too much mass. An abrupt decline in Type Ia supernova blasts between 7.5 billion years ago and 10 billion years ago hints in favor of the two white dwarf merger model, because it predicts that most stars in the early universe are too young to become Type Ia supernovae.

“If supernovae were popcorn, the question is how long before they start popping?” Riess said. “You may have different theories about what is going on in the kernel. If you see when the first kernels popped and how often they popped, it tells you something important about the process of popping corn.”

Findings were reported in the journal The Astrophysical Journal.

 

Eye of Sauron exoplanet

“Eye of Sauron” star hosts rogue planet

Eye of Sauron exoplanet

Back in 2008, Hubble released a stunning image of a very bright star called Fomalhaut which spanned a huge disk of matter around it. The whole picture bared an uncanny resemblance to the eye of Sauron from the Lord of the Rings movies. Also at the time, scientists caught the glimpse of a tiny speck of light deep in the debris disk which they believed was in fact an exoplanet.

Since then, however, followup observations had failed to find the distant world again. In 2010 the bleep of light appeared once again on the astronomers’ radar, but this time it was too far away in the right side of the start to orbit it, which lead many researchers to discount the find.

Newly-released Hubble images show that the debris belt is wider than previously known, spanning a section of space from 14 to nearly 20 billion miles from the star. Apparently, the planet Fomalhaut b follows a  highly eccentric path around the star coming in as close  as 4.6 billion miles, and as far away as 27 billion miles. Moreover, the planet’s orbit isn’t in the same plan as the huge disk, meaning it skews and passes above and below the disk.

“We are shocked. This is not what we expected,” says Paul Kalas of the University of California at Berkeley and the SETI Institute.

The findings suggest that Fomalhaut b is in fact a rogue planet, trailing away at a large distance from its parent star much in the same way as a comet. Its mass is believed to be comparable to that of an icy dwarf world, however its size is believed to be close to that of Jupiter.

“Hot Jupiters get tossed through scattering events, where one planet goes in and one gets thrown out,” says Mark Clampin of NASA’s Goddard Space Flight Center. “This could be the planet that gets thrown out.”

In the video below, astronomers show one possible orbit for Fomalhaut b derived from the analysis of Hubble Space Telescope data between 2004 and 2012. The findings were presented at the  American Astronomical Society 2013 conference.



caption

Amazing high energy, relativistic plasma jets coming out of the Hercules A Galaxy

A long time ago, in a galaxy far, far away… at about 2 billion light years away from Earth lies radio-galaxy Hercules A, also known as 3C 348. At a first glance it looks just like another massive galaxy out there – at least when looking in the visible spectrum. In the radio wavelengths however, the story is completely different. The galaxy has been known for a long time among the brightest extragalactic radio source in the entire sky.

Astronomers using the recently upgraded Karl G. Jansky Very Large Array (VLA) radio telescope in New Mexico, revealed huge jets of material – 1.5 million light-years wide – that literally dwarf the galaxy that emits them (for comparison, our own galaxy is just 0.1 million light years wide).

"It’s both beautiful and fascinating to look at" - astronomer Stefi Baum, of the Rochester Institute of Technology. [Via Nasa News]

“It’s both beautiful and fascinating to look at” – astronomer Stefi Baum, of the Rochester Institute of Technology. [Via Nasa News]

The jets consist of very-high-energy plasma beams, subatomic particles, all interacting with strong magnetic fields are streaming out at nearly the speed of light from the galaxy’s central super-massive black hole which, by comparison, is 1000 times more massive then our Milky Way’s central singularity. At such speeds, the plasma streams become subject to relativistic effects that cause the innermost parts of the jets to be invisible, not even in the radio spectrum, the photons being directed away from our viewpoint.

As the plasma is progressively slowed down by interacting with a very hot, X-ray-emitting cloud of gas that surrounds this galaxy, the two lobes that can be seen in this image, become visible in the radio spectrum. The X-Ray emitting cloud of gas is not shown here, in this optical-radio composite. The ring-like structures visible in the outer portions of the jets point towards a less uniform nature of the plasma stream coming from the super-massive black hole, that perhaps sometimes, comes in bursts.

“The side that has the dust bubbles is the side with the normal looking collimated jet and the side with what looks like more entrained dust is the side that has the very unusual bubbles in the radio,” she said. “We’re perplexed so far.”

[Via Space.com]

“One side has dusty filaments of cold gas that lie along the edges of the radio jet, suggesting they have been dragged along, or entrained, by the out-flowing radio plasma; but the other side of the source shows dusty filaments which resemble two bubbles,” said astronomer Stefi Baum, of the Rochester Institute of Technology (RIT).

[Story via Nasa News]

Hubble stares into the dawn of the Universe – sets another record for oldest galaxy

Using the evergreen Hubble telescope, astronomers from NASA have been able to uncover a previously unseen population of ancient galaxies, observed as they appeared only 350 million to 600 million years after the big bang, when the Universe was still in its infancy.

Picture taken by Hubble, with redshift for remarkable galaxies; the bigger the redshift, the older the galaxy; 11.9 is the current record holder.

The galaxies are located in a patch of the sky called the Ultra Deep Field (UDF). They formed over 13 billion years ago, when the universe was less than 4 percent of its present age, and were intensely studied in a 2012 campaign, called UDF12, by a mixed team of researchers led by Richard Ellis from California Institute of Technology in Pasadena. He used Hubble’s Wide Field Camera 3 (WFC 3) to peer deeper into space in near-infrared light than any previous Hubble observation.

Their results indicate a smooth decline in the number of galaxies looking back in time to about 450 million years after the big bang, and are consistent with the theory that galaxies assembled continuously over time and also may have provided enough radiation to reheat, or re-ionize the universe a few million years after the big bang.

“Our data confirm re-ionization was a gradual process, occurring over several hundred million years, with galaxies slowly building up their stars and chemical elements,” said Brant Robertson of the University of Arizona in Tucson. “There wasn’t a single dramatic moment when galaxies formed. It was a gradual process.”

The Hubble Telescope

The thing is, when you look further and further into space, you also look further into time; the light of the galaxies, which formed over 13 billion years ago, is arriving to Earth just now.

A while ago, I was telling you about how Hubble observed an extremely old galaxy, which appeared 450-500 million years after the big bang. This was a new record at the time, but now, after just 2 months, the record is broken once more: one of these galaxies is believed to have formed 380 million years after the dawn of the Universe. Do you think they can stretch the record even more?

Via NASA

More information on Hubble here

The inset at left shows a close-up of the young dwarf galaxy. This image is a composite taken with Hubble's WFC 3 and ACS. Credit: NASA, ESA, and M. Postman and D. Coe (STScI) and CLASH Team.

Farthest known object in the Universe is 13.3 billion years old

The inset at left shows a close-up of the young dwarf galaxy. This image is a composite taken with Hubble's WFC 3 and ACS. Credit: NASA, ESA, and M. Postman and D. Coe (STScI) and CLASH Team.

The inset at left shows a close-up of the young dwarf galaxy. This image is a composite taken with Hubble’s WFC 3 and ACS. Credit: NASA, ESA, and M. Postman and D. Coe (STScI) and CLASH Team.

NASA scientists have announced they have discovered the farthest object discovered so far in the Universe, a 13.3 billion old galaxy or a mere 420 million years after the Big Bang.

That’s not to say that its 13.3 billion light years away from Earth, since the Universe has expanded greatly since then and the actual distance might be much greater than this figure. It means that light took 13.3 billion years to reach us.

The galaxy has been dubbed  MACS0647-JD and was discovered using a combination of NASA’s Hubble and Spitzer space telescopes, along with gravitational lensing – an interstellar technique that uses distant galaxies to create a zooming effect for the light that passes through them. Without gravitational lensing, this discovery would have been impossible with the current technology employed in telescopes.

“This [magnification galaxy] does what no manmade telescope can do,” Marc Postman, of Baltimore’s Space Telescope Institute, said in a release. “Without the magnification, it would require a Herculean effort to observe this galaxy.”

Essentially, the scientists have looked into the past – 13.3 billion years into the past. What they saw was a galaxy that was only a tiny fraction of the Milky Way. More exactly, it’s been estimated as being only 600 light years wide. For compassion, the Large Magellanic Cloud, a dwarf galaxy companion to the Milky Way, is 14,000 light-years wide. Our Milky Way is 150,000 light-years across.

Since then it has most likely grown, and even collided already with other galaxies. The previous record holder was a gamma ray burst just 600 million years after the Big Bang.

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

source: NASA

Hubble takes brilliant picture of young star population in elderly company

The great pics from Hubble just never end! This time, the brave telescope offered an impressive view of the center of globular cluster NGC 6362. The image of this spherical collection of stars takes a deeper look at the core of the globular cluster, which contains a high concentration of stars with different colors.

Click the pic for full size.

Seeing what appears to be young stars came as quite a surprise, considering that globular clusters are composed of old stars, which, at around 10 billion years old, are way older than the Sun. These clusters are quite common both in our galaxy (over 150 found so far) and in other galaxies. Also, globular clusters are among the oldest objects directly observable in the known Universe, making them living fossils, extremely useful in understanding how galaxies work.

The accepted theory at the moment is that all stars in a globular cluster are about the same age; however, new, high precision measurements performed in numerous globular clusters, primarily with the Hubble Space Telescope have made some astrophysicists doubt this theory. In particular, there appear to be younger, bluer stars, amidst older ones. Researchers dubbed them blue stragglers and NGC 6362 has lots of them.

It’s unclear at the moment how they appear, but since they are usually found in the core regions of clusters, where the concentration of stars is large, the most plausible explanation seems to be that they form as a result of stellar collisions or transfer of material between stars in binary systems.

NGC 6362 is located about 25 000 light-years from Earth in the constellation of Ara (The Altar), and it was discovered all the way back in 1826 by British astronomer James Dunlop.

Artist's rendering of the oldest known spiral galaxy - 11 billion years old. The red area in the upper right corner is a dwarf galaxy that is merging with it. (Dunlap Institute for Astronomy & Astrophysics/Joe Bergeron)

Oldest spiral galaxy is a freak of cosmos

Artist's rendering of the oldest known spiral galaxy - 11 billion years old. The red area in the upper right corner is a dwarf galaxy that is merging with it. (Dunlap Institute for Astronomy & Astrophysics/Joe Bergeron)

Artist’s rendering of the oldest known spiral galaxy – 11 billion years old. The red area in the upper right corner is a dwarf galaxy that is merging with it. (Dunlap Institute for Astronomy & Astrophysics/Joe Bergeron)

In a remarkable discovery, astronomers have found the oldest spiral galaxy to our knowledge –  a three-armed spiral galaxy dating back nearly 11 billion years. It precedes any other previous record holder by about 2 billion years, basically sweeping away the competition. The spiral galaxy is so amazing that it caught astronomers completely by surprise, and even they couldn’t believe what they had stumbled upon at first.

“Our first thought was that we must have the wrong distance for the galaxy,” lead researcher David Law, with the University of Toronto, told Discovery News.

“Then we thought perhaps it was the human brain playing tricks on us. If you look at enough blobby, weird-looking galaxies sooner or later, like a Rorschach blob test, you start to pick out patterns whether or not they’re there,” Law said.

This wasn’t any illusion, any fabric of their imagination. Indeed, the spiral galaxy, dubbed Q2343-BX442 and located in the direction of the Pegasus constellation, had its structured imaged by the Hubble Space Telescope and was confirmed by the Keck II telescope in Hawaii, which studied the object’s internal motions. Studies of spectra from more than 3,600 locations in and around the galaxy revealed that it is, indeed, a rotating spiral galaxy.

The galaxy was present in the early universe, about 3 billion years after the Big Bang, at a time when galaxies were still forming and normally looked clumpy and irregular. “The vast majority of old galaxies look like train wrecks,” said UCLA astronomer Alice E. Shapley, one of the discoverers of the unusual spiral galaxy. “Our first thought was, why is this one so different, and so beautiful?”

Ancient galaxy has spiral days numbered

Ancient spiral galaxies are extremely rare. Actually out of a sample bundle of  306 Hubble Space Telescope imaged ancient galaxies, only ONE presented a spiral structure – the very object of discussion in this article, BX442. This very atypical placement of the spiral galaxy at such an early phase of the Universe is what sparked scientists to investigate it with great scrutiny. The team came to the conclusion that the galaxy’s shape is due to gravitational effects of a smaller galaxy in its vicinity. If that proves to be true, than BX442 wouldn’t had last as a spiral galaxy for too long.

Computer simulations show BX442, a relatively large galaxy with about the same mass as the Milky Way, would only last about 100 million years as a spiral structure.

“We think that we just happened to catch it at a very special time,” Shapley said. “I’d say by today, it probably doesn’t look like a spiral galaxy.”

Our own spiral galaxy, the Milky Way, belongs to a longer-lived class.

“One of the leading mechanisms that we believe explains modern day spirals, such as the Milky Way, is what is called ‘density wave theory,’ which doesn’t need any kind of nearby galaxy. It happens from the disk alone in isolation,” Law said.

The findings were reported in journal Nature.

Colour composite image of the Subaru XMM-Newton deep survey field. In the right panel, the red galaxy at the centre of the image is the most distant galaxy, SXDF-NB1006-2, according to the astronomers. Image by NAOJ

Oldest galaxy discovered so far in the Universe is 12.91 billion years old

Colour composite image of the Subaru XMM-Newton deep survey field. In the right panel, the red galaxy at the centre of the image is the most distant galaxy, SXDF-NB1006-2, according to the astronomers. Image by NAOJ

Colour composite image of the Subaru XMM-Newton deep survey field. In the right panel, the red galaxy at the centre of the image is the most distant galaxy, SXDF-NB1006-2, according to the astronomers. Image by NAOJ

Using the  Subaru and Keck optical/infrared telescopes on Hawaii’s Mauna Kea, a 4,200 metre-high summit which houses the world’s largest observatory for optical, infrared and submillimeter astronomy, a team of Japanese astronomers claim in a recently published paper that they’ve discovered the earliest galaxy found thus far in the known Universe – it is 12.91 billion years old or 12.91 billion light years away.

A light-year is the distance that light travels in a year, about 6 trillion miles – don’t multiply this by the estimated distance from above; it might give you headaches.

At the beginning of the year, scientists at Hubble discovered, what they claim was, the oldest galaxy cluster ever found, at 13.1 billion years, while last year a California team using Hubble said they saw a galaxy from 13.2 billion light-years ago. However, neither of the two teams managed to prove their calculations through other methods.

The Japanese claim for the oldest galaxy found thus far, dubbed “SXDF-NB1006-2”, is more “watertight,” according to other corresponding scientists, since it uses methods that everyone can agree on. Current theory holds that the universe was born of an explosion, called the Big Bang, about 13.7 billion years ago. Using top-notch infrared and optical telescopes, astronomers peer right through the early days of the Universe.

The astronomers are also claiming their research has verified that the proportion of neutral hydrogen gas in the 750m-year-old early universe was higher than it is today. Thus, some 200 to 500 million years after the Big Bang, the dense parts of neutral hydrogen clouds contracted under their own gravity, forming the first stars and galaxies.

“These findings help us to understand the nature of the early universe during the ‘cosmic dawn’, when the light of ancient celestial objects and structures appeared from obscurity,” indicated an NAOJ statement.

“The radiation from this first generation of stars started to heat and reionise the hydrogen in nearby space, eventually leading to the reionisation of the entire universe. This was the era of ‘cosmic reionisation,'” said the NAOJ.

The findings will be published in the journal the Astrophysical Journal.

via Silicon Republic

The Hubble Space Telescope as seen from the departing Space Shuttle Atlantis, flying Servicing Mission 4 (STS-125), the fifth and final human spaceflight to visit the observatory.

Two military spy telescopes, just as big and powerful as Hubble, donated to NASA

The Hubble Space Telescope as seen from the departing Space Shuttle Atlantis, flying Servicing Mission 4 (STS-125), the fifth and final human spaceflight to visit the observatory.

The Hubble Space Telescope as seen from the departing Space Shuttle Atlantis, flying Servicing Mission 4 (STS-125), the fifth and final human spaceflight to visit the observatory. (c) NASA

Now this is something that doesn’t happen everyday, especially from behalf of one of the most paranoid and money-gobbling organizations in the world, an US intelligence agency. According to a recent press release from NRO, the secretive government agency that flies spy satellites, two such functional and high-capable spy satellites were handed over to NASA as gifts. Both are at least just as powerful and big as the Hubble telescope, the civilian space telescope whose findings we’ve all come to know and love.

It’s an extremely surprising feat of technology transfer, from military to civilian purposes, one which may have caught even NASA off guard – I’ll detail why, soon enough. The telescopes were built by private contractors for the National Reconnaissance Office, one of 16 U.S. intelligence agencies. Each have 2.4-meter (7.9-foot) mirrors, just like the Hubble, but they have 100 times the field of view.

“It’s great news,” said NASA astrophysics director Paul Hertz. “It’s real hardware, and it’s got really impressive capabilities.”

Why would the intelligence agency decide to simply give these away? A spokesmen for NRO offered some insight.

“They no longer possessed intelligence-collection uses,” Loretta DeSio said of the telescopes.

She confirmed that the hardware represents an upgrade of Hubble’s optical technology.

“The hardware is approximately the same size as the Hubble but uses newer, much lighter mirror and structure technology,” DeSio said. She added, “Some components were removed before the transfer.”

Which components? “I can’t tell you that,” she said.

In other words, the telescopes, built in the late 1990s and early 2000s, are now technologically outdated, at least for intelligence operations, despite being just as powerful as Hubble. Now that something that’s worth taking into consideration. Moreover, these telescopes worth hundreds of millions of dollars have never seen operation! Instead they’ve been shelved in a warehouse somewhere, of course, classified. And they might find themselves, yet again, blocked in a warehouse, since NASA, on a string budget, doesn’t have the necessary cash to fit them.

The telescopes are space qualified in broad terms, but they’re a long way from being functioning space telescopes, as most of the required instruments for them to become fully compatible civilian space telescopes are missing. Of course, these also need to be launched, tested, safety inspected, manned by an operational staff on the ground and a slew of other logistics.  Using plausible budgets, 2024 would be the earliest date to launch one of the two telescopes unless the agency received additional funding from Congress. “Any dates earlier, like 2019 or 2020, is if money is no object,” Hertz said.

A big chunk out of NASA’s budget is currently being directed towards the development and deployment of the highly anticipated James Webb Space Telescope; a massive, cutting-edge space telescope  designed to orbit 1 million miles from Earth, where it would observe the mid-infrared portion of the electromagnetic spectrum. This would make it capable of gazing through some of the earliest forms of the Universe. It’s not going to be on until  at least 2018, more than four years past the original launch target, and its projected cost is nearing $9 billion.

Nevertheless, it’s still nice of the US intelligence agency to throw a bone down NASA’s way, though if they had added 1% of their budget as well to actually get them into space that would had been incredible. Seriously, this is an incredible gain for NASA, especially in the light of the imminent downfall of the Hubble, which is nearing the end of its designed operational life. Maintenance past its service life is extremely expensive, and short of shuttles, means the Hubble telescope will most likely wash up at the bottom of the Pacific in only a few years time.

Story via Washington Post