Tag: hubble space telescope (page 1 of 3)

Hubble Finds Giant Halo Around the Andromeda Galaxy

May 11, 2015 / / 0 Comments





 Excerpt from hubblesite.org

Scientists using NASA's Hubble Space Telescope have discovered that the immense halo of gas enveloping the Andromeda galaxy, our nearest massive galactic neighbor, is about six times larger and 1,000 times more massive than previously measured. The dark, nearly invisible halo stretches about a million light-years from its host galaxy, halfway to our own Milky Way galaxy. This finding promises to tell astronomers more about the evolution and structure of majestic giant spirals, one of the most common types of galaxies in the universe.

"Halos are the gaseous atmospheres of galaxies. The properties of these gaseous halos control the rate at which stars form in galaxies according to models of galaxy formation," explained the lead investigator, Nicolas Lehner of the University of Notre Dame, Indiana. The gargantuan halo is estimated to contain half the mass of the stars in the Andromeda galaxy itself, in the form of a hot, diffuse gas. If it could be viewed with the naked eye, the halo would be 100 times the diameter of the full Moon in the sky. This is equivalent to the patch of sky covered by two basketballs held at arm's length.

The Andromeda galaxy, also known as M31, lies 2.5 million light-years away and looks like a faint spindle, about 6 times the diameter of the full Moon. It is considered a near-twin to the Milky Way galaxy.

Because the gas in Andromeda's halo is dark, the team looked at bright background objects through the gas and observed how the light changed. This is a bit like looking at a glowing light at the bottom of a pool at night. The ideal background "lights" for such a study are quasars, which are very distant bright cores of active galaxies powered by black holes. The team used 18 quasars residing far behind Andromeda to probe how material is distributed well beyond the visible disk of the galaxy. Their findings were published in the May 10, 2015, edition of The Astrophysical Journal.

Earlier research from Hubble's Cosmic Origins Spectrograph (COS)-Halos program studied 44 distant galaxies and found halos like Andromeda's, but never before has such a massive halo been seen in a neighboring galaxy. Because the previously studied galaxies were much farther away, they appeared much smaller on the sky. Only one quasar could be detected behind each faraway galaxy, providing only one light anchor point to map their halo size and structure. With its close proximity to Earth and its correspondingly large footprint on the sky, Andromeda provides a far more extensive sampling of a lot of background quasars.
"As the light from the quasars travels toward Hubble, the halo's gas will absorb some of that light and make the quasar appear a little darker in just a very small wavelength range," explains co-investigator J. Christopher Howk, also of Notre Dame. "By measuring the dip in brightness in that range, we can tell how much halo gas from M31 there is between us and that quasar."

The scientists used Hubble's unique capability to study the ultraviolet light from the quasars. Ultraviolet light is absorbed by Earth's atmosphere, which makes it difficult to observe with a ground-based telescope. The team drew from about 5 years' worth of observations stored in the Hubble data archive to conduct this research. Many previous Hubble campaigns have used quasars to study gas much farther away than — but in the general direction of — Andromeda, so a treasure trove of data already existed.

But where did the giant halo come from? Large-scale simulations of galaxies suggest that the halo formed at the same time as the rest of Andromeda. The team also determined that it is enriched in elements much heavier than hydrogen and helium, and the only way to get these heavy elements is from exploding stars called supernovae. The supernovae erupt in Andromeda's star-filled disk and violently blow these heavier elements far out into space. Over Andromeda's lifetime, nearly half of all the heavy elements made by its stars have been expelled far beyond the galaxy's 200,000-light-year-diameter stellar disk.

What does this mean for our own galaxy? Because we live inside the Milky Way, scientists cannot determine whether or not such an equally massive and extended halo exists around our galaxy. It's a case of not being able to see the forest for the trees. If the Milky Way does possess a similarly huge halo, the two galaxies' halos may be nearly touching already and quiescently merging long before the two massive galaxies collide. Hubble observations indicate that the Andromeda and Milky Way galaxies will merge to form a giant elliptical galaxy beginning about 4 billion years from now.

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Astronomers Measure Distance to Farthest Galaxy Yet

May 5, 2015 / / 0 Comments



The farthest confirmed galaxy observed to date was identified in this Hubble image of a field of galaxies.  The inset image of the galaxy has been colored blue as suggestive of its young stars. Credit NASA/European Space Agency/Yale/University of California, Santa Cruz


Excerpt from nytimes.com

Leapfrogging backward in time to when the universe was apparently feeling its oats, a group of astronomers reported Tuesday that they had measured a bona fide distance to one of the farthest and thus earliest galaxies known.

The galaxy, more than a few billion light-years on the other side of the northern constellation Boötes, is one of the most massive and brightest in the early universe and goes by the name of EGS-zs8-1. 
It flowered into stardom only 670 million years after the Big Bang.
The light from that galaxy has taken 13 billion years to reach telescopes on Earth. By now, however, since the universe has continued to expand during that time, the galaxy is about 30 billion light-years away, according to standard cosmological calculations.
The new measurements allow astronomers to see the galaxy in its infancy. Despite its relative youth, however, it is already about one-sixth as massive as the Milky Way, which is 10 billion years old. And it is getting bigger, making stars 80 times faster than the Milky Way is making them today. The discovery was reported in The Astrophysical Journal by Pascal Oesch of Yale University and his colleagues.

By the rules of the expanding universe, the farther away a galaxy is, the faster it is retreating from us, measured by the “redshift” of its light being broadened to longer wavelengths, the way an ambulance siren seems to lower its pitch as it goes by.

In the past few years, as astronomers have raced one another into the past with instruments like the Hubble Space Telescope, galaxies have been found that appear even more distant. Those measurements, however, were estimates based on the colors of the objects — so-called photometric redshifts.

The new galaxy stuck out in a survey of distant galaxies by the Hubble and Spitzer space telescopes known as Candels, for Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey. Its redshift was precisely measured with a powerful spectrograph known as Mosfire — Multi-Object Spectrometer for Infrared Exploration — on Keck 1, one of a pair of 10-meter-diameter telescopes on Mauna Kea in Hawaii. That makes it the highest redshift confirmed in this way, said Garth Illingworth, of the University of California, Santa Cruz, one of the astronomers in the study.

How galaxies were able to form and grow so rapidly after the lights came on in the universe is a mystery that will be addressed by a coming generation of instruments like the James Webb Space Telescope and the Thirty Meter Telescope, a goliath planned for Mauna Kea, already home to a dozen telescopes.

Recently, however, construction of the Thirty Meter Telescope, a $1.4 billion project, has been halted by protests by Hawaii residents who feel their mountain has been abused. An echo of that controversy appears in the new paper, in which Dr. Oesch and his colleagues write: “The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.”

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Pluto images reveal intriguing bright spot near pole

April 30, 2015 / / 0 Comments

Excerpt from  latimes.comCheck out the best images yet of the dwarf planet Pluto.The moving images of Pluto and its Texas-sized moon Charon you see below were taken by NASA's New Horizons spacecraft, which has spent nine years on a high-speed j...

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Hubble’s Other Telescope And The Day It Rocked Our World

April 30, 2015 / / 0 Comments

The Hooker 100-inch reflecting telescope at the Mount Wilson Observatory, just outside Los Angeles. Edwin Hubble's chair, on an elevating platform, is visible at left. A view from this scope first told Hubble our galaxy isn't the only one.
The Hooker 100-inch reflecting telescope at the Mount Wilson Observatory, just outside Los Angeles. Edwin Hubble's chair, on an elevating platform, is visible at left. A view from this scope first told Hubble our galaxy isn't the only one.
Courtesy of The Observatories of the Carnegie Institution for Science Collection at the Huntington Library, San Marino, Calif.


Excerpt from hnpr.org

The Hubble Space Telescope this week celebrates 25 years in Earth's orbit. In that time the telescope has studied distant galaxies, star nurseries, planets in our solar system and planets orbiting other stars.

But, even with all that, you could argue that the astronomer for whom the telescope is named made even more important discoveries — with far less sophisticated equipment.

A young Edwin Hubble at Mount Wilson's 100-inch telescope circa 1922, ready to make history.i
A young Edwin Hubble at Mount Wilson's 100-inch telescope circa 1922, ready to make history.
Edwin Hubble Papers/Courtesy of Huntington Library, San Marino, Calif.


In the 1920s, Edwin Hubble was working with the 100-inch Hooker telescope on Mount Wilson, just outside Los Angeles. At the time, it was the largest telescope in the world.

On a chilly evening, I climb up to the dome of that telescope with operator Nik Arkimovich and ask him to show me where Hubble would sit when he was using the telescope. Arkimovich points to a platform near the top of the telescope frame.

"He's got an eyepiece with crosshairs on it," Arkimovich explains. The telescope has gears and motors that let it track a star as it moves across the sky. "He's got a paddle that allows him to make minor adjustments. And his job is to keep the star in the crosshairs for maybe eight hours."

"It's certainly much, much easier today," says John Mulchaey, acting director of the observatories at Carnegie Institution of Science. "Now we sit in control rooms. The telescopes operate brilliantly on their own, so we don't have to worry about tracking and things like this."

Today, astronomers use digital cameras to catch the light from stars and other celestial objects. In Hubble's day, Mulchaey says, they used glass plates.

"At the focus of the telescope you would put a glass plate that has an emulsion layer on it that is actually sensitive to light," he says. At the end of an observing run, the plates would be developed, much like the film in a camera.

The headquarters of the Carnegie observatories is at the foot of Mount Wilson, in the city of Pasadena. It's where Hubble worked during the day.

A century's worth of plates are stored here in the basement. Mulchaey opens a large steel door and ushers me into a room filled with dozens of file cabinets.

"Why don't we go take a look at Hubble's famous Andromeda plates," Mulchaey suggests.

The plates are famous for a reason: They completely changed our view of the universe. Mulchaey points to a plate mounted on a light stand.

"This is a rare treat for you," he says. "This plate doesn't see the light of day very often."


This glass side of a photographic plate shows where Hubble marked novas. The red VAR! in the upper right corner marks his discovery of the first Cepheid variable star — a star that told him the Andromeda galaxy isn't part of our Milky Way.i
This glass side of a photographic plate shows where Hubble marked novas. The red VAR! in the upper right corner marks his discovery of the first Cepheid variable star — a star that told him the Andromeda galaxy isn't part of our Milky Way.
Courtesy of the Carnegie Observatories 
To the untrained eye, there's nothing terribly remarkable about the plate. But Mulchaey says what it represents is the most important discovery in astronomy since Galileo.

The plate shows the spiral shape of the Andromeda galaxy. Hubble was looking for exploding stars called novas in Andromeda. Hubble marked these on the plate with the letter "N."

"The really interesting thing here," Mulchaey says, "is there's one with the N crossed out in red — and he's changed the N to VAR with an exclamation point."

Hubble had realized that what he was seeing wasn't a nova. VAR stands for a type of star known as a Cepheid variable. It's a kind of star that allows you to make an accurate determination of how far away something is. This Cepheid variable showed that the Andromeda galaxy isn't a part of our galaxy.

At the time, most people thought the Milky Way was it — the only galaxy in existence.

"And what this really shows is that the universe is much, much bigger than anybody realizes," Mulchaey says.
It was another blow to our human conceit that we are the center of the universe.

Hubble went on to use the Mount Wilson telescope to show the universe was expanding, a discovery so astonishing that Hubble had a hard time believing it himself.

If Hubble could make such important discoveries with century-old equipment, it makes you wonder what he might have turned up if he'd had a chance to use the space telescope that bears his name.

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New Light on Our Accelerating Universe –"Not as Fast as We Thought"

April 12, 2015 / / 0 Comments

 A Type Ia supernova, SN1994D, is shown exploding in lower left corner of the image at the top of the page of the galaxy NGC 4526 taken by the Hubble Space Telescope. (High-Z Supernova Search Team, HST, NASA)Excerpt from dailygalaxy.com Cer...

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Warp in spacetime lets astronomers watch the same star explode four times

March 8, 2015 / / 0 Comments



Excerpt from csmonitor.com

Thanks to a phenomenon known as gravitational lensing, the Hubble Space Telescope has captured four images of the same supernova explosion.

For the first time, a cosmic magnifying glass has allowed scientists to see the same star explosion four times, possibly offering a revealing glimpse into these explosive stellar deaths and the nature of the accelerating universe.

Astronomers using the Hubble Space Telescope have captured four images of a supernova explosion in deep space thanks to a galaxy located between Earth and the massive star explosion. You can see how Hubble saw the supernova in this NASA video. The galaxy cluster warped the fabric of space and time around it — like a bowling ball placed on a bed sheet — allowing scientists to see the supernova in four images.

"It was predicted 50 years ago that a supernova could be gravitationally lensed like this, but it's taken a long time for someone to find an example," lead study author Patrick Kelly, an astronomer at the University of California, Berkeley told Space.com. "It's fun to have been able to find the first one." 

The supernova, which was discovered on Nov. 11, 2014, is located about 9.3 billion light-years away from Earth, near the edge of the observable universe. The researchers have named the distant supernova SN Refsdal in honor of the late Norwegian astrophysicist Sjur Refsdal, a pioneer of gravitational lensing studies. Due to gravitational lensing, "the supernova appears 20 times brighter than its normal brightness," study co-author Jens Hjorth, head of the Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen, said in a statement.
The lensing galaxy, which is about 5 billion light-years from Earth, is part of a large cluster of galaxies known MACS J1149.6+2223. In 2009, astronomers discovered that this cluster was the source of the largest known image of a spiral galaxy ever seen through a gravitational lens.

The four images of the supernova each appeared separately over the course of a few weeks. This is because light can take various paths around and through a gravitational lens, arriving at Earth at different times.

Using gravity as a lens

Gravity is created when matter warps the fabric of reality. The greater the mass of an object, the more space-time curves around that object and the stronger its gravitational pull, the discovery enshrined in Einstein's theory of general relativity, which celebrates its centennial this year.

As a result, gravity can also bend light like a lens, meaning objects see n behind powerful gravitational fields, such as those of massive galaxies, are magnified. Gravitational lensing was first discovered in 1979, and today gravitational lenses can help astronomers see features otherwise too distant and faint to detect with even the largest telescopes.

"These gravitational lenses are like a natural magnifying glass. It's like having a much bigger telescope," Kelly said in a statement. "We can get magnifications of up to 100 times by looking through these galaxy clusters."

When light is far from a gravitationally lensing mass, or if the gravitationally lensing mass is not especially large, only "weak lensing" occurs, barely distorting the light. However, when the light comes from almost exactly behind the gravitationally lensing mass, "strong lensing" can happen. 

When a strongly lensed object occupies a large patch of space — for instance, if it's a galaxy — it can get smeared into an "Einstein ring" surrounding a gravitationally lensing mass. However, strong lensing of small, pointlike items — for instance, super-bright objects known as quasars — often produces multiple images surrounding the gravitationally lensing mass, resulting in a so-called "Einstein cross."

The observations of SN Refsdal mark the first time astronomers on Earth have witnessed strong lensing of a  supernova, with four images of an exploding star arrayed as an Einstein cross.

An expanding universe

These new findings could help scientists measure the accelerating rate at which the universe is expanding, researchers say.

A computer model of the lensing cluster suggests the scientists missed chances to see the lensed supernova 50 and 10 years ago. However, the model also suggests more images of the explosion will repeat again within the next 10 years.

The timing of when all these images of the supernova arrive depends on the gravitational pull of the matter generating the gravitational lens. So, by measuring those times, the researchers hope to map how visible normal matter and invisible dark matter is distributed in the lensing galaxy.

Dark matter is currently one of the greatest mysteries in science, a poorly understood substance thought to make up five-sixths of all matter in the universe. A better understanding of how dark matter is behaving in this gravitationally lensing cluster might help shed light on the material's nature, Kelly said.

Analyzing when the images arrive could also help scientists pinpoint the rate at which the universe is expanding. Although there are already several ways to measure the cosmic expansion rate, "there has been a lot of heated debate between different methods, so it'd be interesting to see how this new technique might affect the area," Kelly said. "It's always nice to have completely independent measurements of the same quantity."

The scientists detailed their findings in the March 6 issue of the journal Science.

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Hubble’s ‘Einstein Cross’ Marks the Space-Warping Spot

March 6, 2015 / / 0 Comments


Image: Einstein Cross revealed
Flash from the supernova's blast has been warped into four points of light surrounding an elliptical galaxy in a cluster called MACS J1149.2+2223, which is 5 billion light-years away in the constellation Leo.


Excerpt from nbcnews.com
By Alan Boyle


One hundred years after Albert Einstein published his theory of general relativity, the Hubble Space Telescope has provided a demonstration of the theory at work: a picture of a distant galaxy so massive that its gravitational field is bending the light from an even more distant supernova. 

The image, released Thursday, shows how the flash from the supernova's blast has been warped into four points of light surrounding an elliptical galaxy in a cluster called MACS J1149.2+2223, which is 5 billion light-years away in the constellation Leo. 

"It really threw me for a loop when I spotted the four images surrounding the galaxy," Patrick Kelly, an astronomer from the University of California at Berkeley, said in a news release. "It was a complete surprise." 

Maybe it shouldn't have been. The configuration is known as an Einstein Cross. It's a well-known but rarely seen effect of gravitational lensing, which is in line with Einstein's assertion that a massive object warps the fabric of space-time — and thus warps the path taken by light rays around the object. 

In this case, the light rays are coming from a stellar explosion that's directly behind the galaxy, but 4.3 million light-years more distant. Computer models suggest that the four-pointed cross will eventually fade away, to be followed within the next five years by the reappearance of the supernova's flash as a single image. 

Kelly is part of a research collaboration known as the Grism Lens Amplified Survey from Space, or GLASS. The collaboration is working with the Frontier Field Supernova team, or FrontierSN, to analyze the exploding star. He's also the lead author of a paper on the phenomenon that's being published this week by the journal Science as part of a package marking the 100th anniversary of Einstein's general relativity theory. 

The researchers suggest that a high-resolution analysis of the gravitational lensing effect can lead to better measurements of cosmic distances and galactic masses, including the contribution from dark matter. The Hubble team says the faraway supernova has been named "Refsdal" in honor of Norwegian astronomer Sjur Refsdal, who proposed using time-delayed images from a lensed supernova to study the expansion of the universe. 

"Astronomers have been looking to find one ever since," UCLA astronomer Tommaso Treu, the GLASS project's principal investigator, said in Thursday's news release. "The long wait is over!" 

The Einstein Cross is the subject of a Google+ Hangout at 3 p.m. ET Thursday, presented by the Hubble science team. You can watch the event now or later via YouTube. Check out a preprint version of the Science report.

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Cluster Filled with Dark Matter May House ‘Failed Galaxies’

February 21, 2015 / / 0 Comments

The Coma Cluster


Excerpt space.com

 A strange set of 48 galaxies appears to be rich in dark matter and lacking in stars, suggesting that they may be so-called "failed" galaxies, a new study reports.

The galaxies in question are part of the Coma Cluster, which lies 300 million light-years from Earth and packs several thousand galaxies into a space just 20 million light-years across. To study them, Pieter van Dokkum of Yale University and his colleagues used the Dragonfly Telephoto Array in New Mexico.

The array's eight connected Canon telephoto lenses allow the researchers to search for extremely faint objects that traditional telescope surveys miss. Often, such as when the researchers used the array to search for the faint glow that dark matter might create, the hunt comes up empty. 


But when van Dokkum and his colleagues looked toward the Coma Cluster, they found a pleasant surprise.

"We noticed all these faint little smudges in the images from the Dragonfly telescope," van Dokkum told Space.com.

The mysterious blobs nagged at van Dokkum, compelling him to look into the objects further. Fortuitously, NASA's Hubble Space Telescope had recently captured one of these objects with its sharp eye. 

"It turned out that they're these fuzzy blobs that look somewhat like dwarf spheroidal galaxies around our own Milky Way," van Dokkum said. "So they looked familiar in some sense … except that if they are at the distance of the Coma Cluster, they must be really huge."

And with very few stars to account for the mass in these galaxies, they must contain huge amounts of dark matter, the researchers said. In fact, to stay intact, the 48 galaxies must contain 98 percent dark matter and just 2 percent "normal" matter that we can see. The fraction of dark matter in the universe as a whole is thought to be around 83 percent. 

But before making this claim, the team had to verify that these blobs really are as distant as the Coma Cluster. (In fact, the team initially thought the galaxies were much closer.). But even in the Hubble image the stars were not resolved. If Hubble — one of the most powerful telescopes in existence — can't resolve the stars, those pinpricks of light must be pretty far away, study team members reasoned. 

Now, van Dokkum and his colleagues have definitive evidence: They've determined the exact distance to one of the galaxies. The team used the Keck Telescope in Hawaii to look at one of the objects for two hours. This gave them a hazy spectrum, from which they were able to tease out the galaxy's recessional velocity — that is, how fast it is moving away from Earth.

That measure traces back to the Hubble Telescope's namesake. In 1929, American astronomer Edwin Hubble discovered one of the simplest and most surprising relationships in astronomy: The more distant a galaxy, the faster it moves away from the Milky Way.

Today, astronomers use the relationship to measure a galaxy's recessional velocity and thus calculate the galaxy's distance. In this case, the small fuzzy blob observed with Keck was moving away from Earth at 15.7 million mph (25.3 million km/h). That places it at 300 million light-years away from Earth, the distance of the Coma Cluster.

So the verdict is officially in: These galaxies must be associated with the Coma Cluster and therefore must be extremely massive.
"It looks like the universe is able to make unexpected galaxies," van Dokkum said, adding that there is an amazing diversity of massive galaxies.

But the clusters still present a mystery: The team doesn't know why they have so much dark matter and so few stars.

Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma. Test your stellar smarts with this quiz.
One possibility is that these are "failed" galaxies. A galaxy's first supernova explosions will drive away huge amounts of gas. 

Normally, the galaxy has such a strong gravitational pull that most of the expelled gas falls back onto the galaxy and forms the next generations of stars. But maybe the strong gravitational pull of the other galaxies in the Coma Cluster interfered with this process, pulling the gas away.

"If that happened, they had no more fuel for star formation and they were sort of stillborn galaxies where they started to get going but then failed to really build up a lot of stars," said van Dokkum, adding that this is the most likely scenario. 

Another possibility is that these galaxies are in the process of being ripped apart. But astronomers expect that if this were the case, the galaxies would be distorted and streams of stars would be flowing away from them. Because these effects don't appear, this scenario is very unlikely.

The next step is to try to measure the individual motions of stars within the galaxies. If the team knew those stars' speeds, it could calculate the galaxies' exact mass, and therefore the amount of dark matter they contain. If the stars move faster, the galaxy is more massive. And if they move slower, the galaxy is less massive. 
However, this would require a better spectrum than the one the team has right now.

"But it's not outside the realm of what's possible," van Dokkum assured. "It's just very hard."

The original study has been published in Astrophysical Journal Letters. You can read it for free on the preprint site arXiv.org.

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Mysterious plumes in Mars’ atmosphere baffle astronomers

February 17, 2015 / / 0 Comments




Excerpt from thespacereporter.com

Astronomers are baffled by images of plumes rising from Mars’ atmosphere in images taken by amateur astronomers in March and April 2012.

The plumes were present for about 10 days though their shapes and sizes changed rapidly during that time, from finger-like tendrils to spherical blobs.

Researchers have proposed several possible explanations for the plumes, which are discussed in an article just published in the journal Nature.

Each of the theories being considered poses problems. One theory, for instaqnce, proposes the plumes are caused by the same magnetic influence that causes the aurora borealis, or Northern Lights, on Earth. The movement of electrically charged particles from the Sun, driven by the solar wind towards Earth’s poles, results in these particles colliding with molecules of gas. These collisions produce the strange lights known as aurorae.

In the study, the researchers admit, “Mars aurorae have been observed near where the plume occurs, a region with a large anomaly in the crustal magnetic field that can drive the precipitation of solar wind particles into the atmosphere.”
The problem with this theory is this would only happen if the Sun released an exceptional amount of energetic particles during the time the plumes were seen. Yet the level of solar output in 2012 was nowhere near sufficient to release such a powerful stream of particles, the authors of the paper acknowledge.

They move on to consider another option, namely that the plumes might be clouds high in the Martian atmosphere.

A highly reflective cloud of either water ice, carbon dioxide ice, or dust particles could explain the plumes. But according to computer models, the presence of these clouds “would require exceptional deviations from standard atmospheric circulation models to explain cloud formations at such high altitudes,” explained the paper’s lead author, Agustin Sanchez-Lavega of the Universidad del Pais Vasco in Spain.

The plumes were seen approximately 120 miles (200 km) from Mars’ surface, which is problematic because the highest Martian clouds are seen is 60 miles (100 km) above the planet’s surface. The only way water can condense so far up is if the temperature in that part of Mars’ atmosphere drops 370 degrees Fahrenheit, or 50 degrees Kelvin, below its norm.

Condensation of carbon dioxide would require twice this temperature drop.

A third theory posits the flumes are caused by atmospheric dust. A wind powerful enough to transport dust 111 miles (180 km) above Mars’ surface could occur only around noon, when the Sun’s heat would be strong enough to create such wind currents.

However, the plumes were seen not at noon but in the mornings along the terminator that separates the planet’s day and night sides.
Recently, data from the Hubble Space Telescope was found showing the plumes back in 1997.

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Planck telescope puts new datestamp on first stars

February 10, 2015 / / 0 Comments


Polarisation of the sky
Planck has mapped the delicate polarisation of the CMB across the entire sky



Excerpt from bbc.com

Scientists working on Europe's Planck satellite say the first stars lit up the Universe later than previously thought.

The team has made the most precise map of the "oldest light" in the cosmos.

Earlier observations of this radiation had suggested the first generation of stars were bursting into life by about 420 million years after the Big Bang.

Planck's data indicates this great ignition was well established by some 560 million years after it all began.

"This difference of 140 million years might not seem that significant in the context of the 13.8-billion-year history of the cosmos, but proportionately it's actually a very big change in our understanding of how certain key events progressed at the earliest epochs," said Prof George Efstathiou, one of the leaders of the Planck Science Collaboration.

Subtle signal

The assessment is based on studies of the "afterglow" of the Big Bang, the ancient light called the Cosmic Microwave Background (CMB), which still washes over the Earth today.
Prof George Efstathiou: "We don't need more complicated explanations"

The European Space Agency's (Esa) Planck satellite mapped this "fossil" between 2009 and 2013.

It contains a wealth of information about early conditions in the Universe, and can even be used to work out its age, shape and do an inventory of its contents.

Scientists can also probe it for very subtle "distortions" that tell them about any interactions the CMB has had on its way to us.

Forging elements

One of these would have been imprinted when the infant cosmos underwent a major environmental change known as re-ionisation.

Prof Richard McMahon: "The two sides of the bridge now join"
It is when the cooling neutral hydrogen gas that dominated the Universe in the aftermath of the Big Bang was then re-energised by the ignition of the first stars.

These hot giants would have burnt brilliant but brief lives, producing the very first heavy elements. But they would also have "fried" the neutral gas around them - ripping electrons off the hydrogen protons.

And it is the passage of the CMB through this maze of electrons and protons that would have resulted in it picking up a subtle polarisation.

ImpressionImpression: The first stars would have been unwieldy behemoths that burnt brief but brilliant lives


The Planck team has now analysed this polarisation in fine detail and determined it to have been generated at 560 million years after the Big Bang.

The American satellite WMAP, which operated in the 2000s, made the previous best estimate for the peak of re-ionisation at 420 million years. 

The problem with that number was that it sat at odds with Hubble Space Telescope observations of the early Universe.

Hubble could not find stars and galaxies in sufficient numbers to deliver the scale of environmental change at the time when WMAP suggested it was occurring.

Planck's new timing "effectively solves the conflict," commented Prof Richard McMahon from Cambridge University, UK.

"We had two groups of astronomers who were basically working on different sides of the problem. The Planck people came at it from the Big Bang side, while those of us who work on galaxies came at it from the 'now side'. 

"It's like a bridge being built over a river. The two sides do now join where previously we had a gap," he told BBC News.

That gap had prompted scientists to invoke complicated scenarios to initiate re-ionisation, including the possibility that there might have been an even earlier population of giant stars or energetic black holes. Such solutions are no longer needed.

No-one knows the exact timing of the very first individual stars. All Planck does is tell us when large numbers of these stars had gathered into galaxies of sufficient strength to alter the cosmic environment. 

By definition, this puts the ignition of the "founding stars" well before 560 million years after the Big Bang. Quite how far back in time, though, is uncertain. Perhaps, it was as early as 200 million years. It will be the job of the next generation of observatories like Hubble's successor, the James Webb Space Telescope, to try to find the answer.

JWSTBeing built now: The James Webb telescope will conduct a survey of the first galaxies and their stars
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The history of the Universe

Graphic of the history of time
  • Planck's CMB studies indicate the Big Bang was 13.8bn years ago
  • The CMB itself can be thought of as the 'afterglow' of the Big Bang
  • It spreads across the cosmos some 380,000 years after the Big Bang
  • This is when the conditions cool to make neutral hydrogen atoms
  • The period before the first stars is often called the 'Dark Ages'
  • When the first stars ignite, they 'fry' the neutral gas around them
  • These giants also forge the first heavy elements in big explosions
  • 'First Light', or 'Cosmic Renaissance', is a key epoch in history
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The new Planck result is contained in a raft of new papers just posted on the Esa website. 

These papers accompany the latest data release from the satellite that can now be used by the wider scientific community, not just collaboration members.
Dr Andrew Jaffe: "The simplest models for inflation are ruled out"
Two years ago, the data dump largely concerned interpretations of the CMB based on its temperature profile. It is the CMB's polarisation features that take centre-stage this time.
It was hoped that Planck might find direct evidence in the CMB's polarisation for inflation - the super-rapid expansion of space thought to have occurred just fractions of a second after the Big Bang. This has not been possible. But all the Planck data - temperature and polarisation information - is consistent with that theory, and the precision measurements mean new, tighter constraints have been put on the likely scale of the inflation signal, which other experiments continue to chase.
What is clear from the Planck investigation is that the simplest models for how the super-rapid expansion might have worked are probably no longer tenable, suggesting some exotic physics will eventually be needed to explain it.
"We're now being pushed into a parameter space we didn't expect to be in," said collaboration scientist Dr Andrew Jaffe from Imperial College, UK. "That's OK. We like interesting physics; that's why we're physicists, so there's no problem with that. It's just we had this naïve expectation that the simplest answer would be right, and sometimes it just isn't."

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Dawn Probe’s Views of Ceres Add to Mystery of the Glowing White Spots

February 5, 2015 / / 0 Comments



Image: Ceres
NASA / JPL-Caltech / UCLA / MPS / DLR / IDA
A picture of Ceres from the Dawn spacecraft shows craters with central peaks on the surface. The pictures will become clearer as Dawn comes closer over the next month.

Excerpt from nbcnews.com

NASA's Dawn spacecraft is snapping increasingly detailed pictures of the dwarf planet Ceres as it zooms in for next month's rendezvous, but so far the images have only heightened the mystery surrounding bright spots on the surface. 
The pictures released Thursday show that Ceres — the largest asteroid as well as the closest and smallest known dwarf planet — is pockmarked by craters. The craters are to be expected: The 590-mile-wide (950-kilometer-wide) mini-world has been pummeled for billions of years by other objects in the asteroid belt. But the white spots? They're a real puzzle. 
One spot in particular has shown up prominently in pictures from the Hubble Space Telescope and from Dawn, which was launched back in 2007 to study Ceres and its sister asteroid Vesta. The latest pictures, taken on Wednesday from a distance of about 90,000 miles (145,000 kilometers), appear to show still more bright blips on Ceres. Are they patches of light material or ice at the bottom of craters? Or frost on the top of prominences?
"We are at a phase in the mission where the curtain is slowly being pulled back on the nature of the surface," UCLA planetary scientist Chris Russell, the principal investigator for the $466 million mission, told NBC News in an email. "But the surface is different from that of other planets, and at this stage the increasing resolution presents more mysteries rather than answers them." 
Russell said the science team was particularly interested in the big bright spot and the region surrounding it. 
"Naively we expect a bright region to be fresh and a dark region to be old. So the surface of Ceres seems to have a number of circular features of varying freshness on a predominantly dark, presumably old surface," Russell wrote. "The one type of feature that clearly came into view this time were examples of central peak craters with overall similarity to large lunar craters." 
The mysteries will be cleared up by the time Dawn enters orbit around Ceres in March. OR WILL THEY?


Click to zoom

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How Obama wants to spend Americans’ money next year: an agency-by-agency look

February 3, 2015 / / 0 Comments


PHOTO: President Barack Obama's new $4 trillion budget plan is distributed by the Senate Budget Committee as it arrives on Capitol Hill in Washington, early Monday, Feb. 02, 2015. The fiscal blueprint for the budget year that begins Oct. 1, seeks to raise taxes on wealthier Americans and corporations and use the extra income to lift the fortunes of families who have felt squeezed during tough economic times. Republicans, who now hold the power in Congress, are accusing the president of seeking to revert to tax-and-spend policies that will harm the economy while failing to do anything about soaring spending on government benefit programs. (AP Photo/J. Scott Applewhite)
President Barack Obama's new $4 trillion budget plan is distributed by the Senate Budget Committee as it arrives on Capitol Hill in Washington, early Monday, Feb. 02, 2015. The fiscal blueprint for the budget year that begins Oct. 1, seeks to raise taxes on wealthier Americans and corporations and use the extra income to lift the fortunes of families who have felt squeezed during tough economic times. Republicans, who now hold the power in Congress, are accusing the president of seeking to revert to tax-and-spend policies that will harm the economy while failing to do anything about soaring spending on government benefit programs. (AP Photo/J. Scott Applewhite)


Excerpt from therepublic.com 

WASHINGTON — Sure, $4 trillion sounds like a lot. But it goes fast when your budget stretches from aging highways to medical care to space travel and more.

Here's an agency-by-agency look at how President Barack Obama would spend Americans' money in the 2016 budget year beginning Oct. 1:

HEALTH AND HUMAN SERVICES
Up or down? Up 4.3 percent
What's new? Medicare could negotiate prices for cutting-edge drugs.
Highlights:
— The president's proposed health care budget asks Congress to authorize Medicare to negotiate what it pays for high-cost prescription drugs and for biologics, including advanced medications for diseases such as rheumatoid arthritis. Currently, private insurers bargain on behalf of Medicare beneficiaries. Drug makers have beaten back prior proposals to give Medicare direct pricing power. But the introduction of a $1,000-a-pill hepatitis-C drug last year may have shifted the debate.
— Tobacco taxes would nearly double, to extend health insurance for low-income children. The federal cigarette tax would rise from just under $1.01 per pack to about $1.95 per pack. Taxes on other tobacco products also would go up. That would provide financing to pay for the Children's Health Insurance Program through 2019. The federal-state program serves about 8 million children, and funding technically expires Sept. 30. The tobacco tax hike would take effect in 2016.
— Starting in 2019, the proposal increases Medicare premiums for high-income beneficiaries and adds charges for new enrollees. The charges for new enrollees include a home health copayment, changes to the Part B deductible, and a premium surcharge for seniors who've also purchased a kind of supplemental insurance whose generous benefits are seen as encouraging overuse of Medicare services.
— There's full funding for ongoing implementation of Obama's health care law.
—The plan would end the budget sequester's 2 percent cut in Medicare payments to service providers and repeal another budget formula that otherwise will result in sharply lower payments for doctors. But what one hand gives, the other hand takes away. The budget also calls for Medicare cuts to hospitals, insurers, drug companies and other service providers.
The numbers:
Total spending: $1.1 trillion, including about $1 trillion on benefit programs including Medicare and Medicaid, already required by law.
Spending that needs Congress' annual approval: $80 billion.
NASA
Up or down? Up 2.9 percent
What's new? Not much. Just more money for planned missions.
Highlights:
—The exploration budget — which includes NASA's plans to grab either an asteroid or a chunk of an asteroid and haul it closer to Earth for exploration by astronauts — gets a slight bump in funding. But the details within the overall exploration proposal are key. The Obama plan would put more money into cutting-edge non-rocket space technology; give a 54 percent spending jump to money sent to private firms to develop ships to taxi astronauts to the International Space Station; and cut by nearly 12 percent spending to build the next government big rocket and capsule to carry astronauts. Congress in the past has cut the president's proposed spending on the private firms and technology and boosted the spending on the government big rocket and capsule.
—The president's 0.8 percent proposed increase in NASA science spending is his first proposed jump in that category in four years. It's also the first proposed jump in years in exploring other planets. It includes extra money for a 2020 unmanned Martian rover and continued funding for an eventual robotic mission to Jupiter's moon Europa. But the biggest extra science spending goes to study Earth.
— Obama's budget would cut aeronautics research 12 percent from current spending and slash NASA's educational spending by 25 percent. It also slightly trims the annual spending to build the over-budget multi-billion dollar James Webb Space Telescope, which will eventually replace the Hubble Space Telescope and is scheduled to launch in 2018.
The numbers:
Total spending: $18.5 billion
Spending that needs Congress' annual approval: $18.5 billion
TRANSPORTATION
Up or down? Up 31 percent
What's new? A plan to tackle an estimated $2 trillion in deferred maintenance for the nation's aging infrastructure by boosting highway and transit spending to $478 billion over six years.
Highlights:
— The six-year highway and transit plan would get a one-time $238 billion infusion from the general treasury. Some of the money would be offset by taxing the profits of U.S. companies that haven't been paying taxes on income made overseas. That infusion comes on top of the $35 billion a year that normally comes from gasoline and diesel taxes and other transportation fees.
— The proposal also includes tax incentives to encourage private investment in infrastructure, and an infrastructure investment bank to help finance major transportation projects.
— The new infrastructure investment would be front-loaded. The budget proposes to spend the money over six years and pay for the programs over 10 years.
— The proposal also includes a new Interagency Infrastructure Permitting Improvement Center to coordinate efforts across nearly 20 federal agencies and bureaus to speed up the permitting process. For example, the Coast Guard, Corps of Engineers and Transportation Department are trying to synchronize their reviews of projects such as bridges that cross navigation channels.
The numbers:
Total spending: $94.5 billion, including more than $80 billion already required by law, mostly for highway and transit aid to states and improvement grants to airports.
Spending that needs Congress' annual approval: $14.3 billion.
Associated Press writers Ricardo Alonso-Zaldivar, Seth Borenstein, Joan Lowy and Connie Cass contributed to this report.

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Hubble Juiced! ~ CU-Boulder to Design Space Telescope 1000 Times Sharper than Hubble

January 31, 2015 / / 0 Comments



CU-Boulder to Design Space Telescope 1000 Times Sharper than Hubble
The Hubble Space Telescope


Excerpt from utahpeoplespost.com


Researchers from the Department of Astrophysical and Planetary Sciences at the University of Colorado Boulder are currently working on an improved version of space telescope that could provide space images nearly 1,000 times sharper than those provided by long-running Hubble.

The new space telescope, dubbed the Aragoscope, is named after a French astronomer called Francois Arago. The new telescope is exclusively designed by the CU- Boulder scientists and involves a brand new technology developed by the university. According to its designers, the space optical instrument would be lighter, slimmer, and sharper than Hubble.

Additionally, the Aragoscope will involve several independent pieces that can be later assembled in space. So, the launching costs of these smaller building blocks will be significantly reduced.
Traditionally, space telescopes have essentially been monolithic pieces of glass like the Hubble Space Telescope. But the heavier the space telescope, the more expensive the cost of the launch,”
said Anthony Harness, one of the researchers involved in the project and doctoral student at the CU-Boulder.

However, the new instrument will not replace Hubble, which is scheduled to be shut down in 5 years time. Last year, Hubble had its fifth and final maintenance service, and it was still in a pretty good shape although one of its six gyroscopes couldn’t be stabilized. Despite Hubble has been operating since 1990, NASA engineers hope that it will make it to its 30th anniversary.

If Hubble remains operational, NASA plans to use it along with its successor, the James Webb Space Telescope, which is scheduled to be launched in October 2018. Astronomers hope that the two space telescopes, which use two different imaging methods, would help them better understand the origins and early evolution of the universe.

But the UC-Boulder team claim that their new space telescope would surpass Hubble with its enhanced capacity of spotting distant Earth-like planets in the depths of a remote universe...

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