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Old 05-14-2011, 05:26 PM   #61
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Uranus image celebrates Herschel - the man and the machine
http://www.bbc.co.uk/news/science-environment-13389940

Happy Birthday H.

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Old 07-07-2011, 06:29 PM   #62
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ESA: Exploding stars can make good dust factories:
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7 July 2011

ESA’s Herschel space observatory has discovered that titanic stellar explosions can be excellent dust factories. In space, the dust mixes with gas to become the raw material for new stars, planets and, ultimately, life. This discovery may solve a mystery of the early Universe.

The discovery was made while Herschel was charting emission from cold dust in the Large Magellanic Cloud, a small galaxy near to the Milky Way. It is the perfect observatory for the job because cold dust radiates far-infrared light, the wavelengths Herschel is designed to detect.

Herschel saw a spot of light at the location of supernova 1987A, an exploding star first seen from Earth in February 1987, and the closest known supernova in the past 400 years.

Since then, astronomers have been studying the remains of the explosion as its blast wave expands into its surroundings.

Herschel’s images are the first clear-cut far-infrared observations of SN1987A. They reveal cold dust grains at about –250ºC, emitting more than 200 times the Sun’s energy.

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NASA / NASA JPL:
Herschel Helps Solve Mystery of Cosmic Dust Origins

PASADENA, CALIF. -- New observations from the infrared Herschel Space Observatory reveal that an exploding star expelled the equivalent of between 160,000 and 230,000 Earth masses of fresh dust. This enormous quantity suggests that exploding stars, called supernovae, are the answer to the long-standing puzzle of what supplied our early universe with dust.

"This discovery illustrates the power of tackling a problem in astronomy with different wavelengths of light," said Paul Goldsmith, the NASA Herschel project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is not a part of the current study. "Herschel's eye for longer-wavelength infrared light has given us new tools for addressing a profound cosmic mystery."

Herschel is led by the European Space Agency with important contributions from NASA.

Cosmic dust is made of various elements, such as carbon, oxygen, iron and other atoms heavier than hydrogen and helium. It is the stuff of which planets and people are made, and it is essential for star formation. Stars like our sun churn out flecks of dust as they age, spawning new generations of stars and their orbiting planets.

Astronomers have for decades wondered how dust was made in our early universe. Back then, sun-like stars had not been around long enough to produce the enormous amounts of dust observed in distant, early galaxies. Supernovae, on the other hand, are the explosions of massive stars that do not live long.

Click on images for details
This layout compares two pictures of a supernova remnant called SN 1987A -- the left image was taken by the Herschel Space Observatory, and the right is an enlarged view of the circled region at left, taken with NASA's Hubble Space Telescope.
Image credit: ESA/NASA-JPL/UCL/STScI
This plot shows energy emitted from a supernova remnant called SN 1987A.
Image credit: ESA/NASA-JPL/UCL/STScI


The new Herschel observations are the best evidence yet that supernovae are, in fact, the dust-making machines of the early cosmos.

"The Earth on which we stand is made almost entirely of material created inside a star," explained the principal investigator of the survey project, Margaret Meixner of the Space Telescope Science Institute, Baltimore, Md. "Now we have a direct measurement of how supernovae enrich space with the elements that condense into the dust that is needed for stars, planets and life."

The study, appearing in the July 8 issue of the journal Science, focused on the remains of the most recent supernova to be witnessed with the naked eye from Earth. Called SN 1987A, this remnant is the result of a stellar blast that occurred 170,000 light-years away and was seen on Earth in 1987. As the star blew up, it brightened in the night sky and then slowly faded over the following months. Because astronomers are able to witness the phases of this star's death over time, SN 1987A is one of the most extensively studied objects in the sky.

A new view from NASA's Hubble Space Telescope showing how supernova 1987A has recently brightened is at http://hubblesite.org/newscenter/arc...leases/2011/21 .

Initially, astronomers weren't sure if the Herschel telescope could even see this supernova remnant. Herschel detects the longest infrared wavelengths, which means it can see very cold objects that emit very little heat, such as dust. But it so happened that SN 1987A was imaged during a Herschel survey of the object's host galaxy -- a small neighboring galaxy called the Large Magellanic Cloud (it's called large because it's bigger than its sister galaxy, the Small Magellanic Cloud).

After the scientists retrieved the images from space, they were surprised to see that SN 1987A was aglow with light. Careful calculations revealed that the glow was coming from enormous clouds of dust -- consisting of 10,000 times more material than previous estimates. The dust is minus 429 to minus 416 degrees Fahrenheit (about minus 221 to 213 Celsius) -- colder than Pluto, which is about minus 400 degrees Fahrenheit (204 degrees Celsius).

"Our Herschel discovery of dust in SN 1987A can make a significant understanding in the dust in the Large Magellanic Cloud," said Mikako Matsuura of University College London, England, the lead author of the Science paper. "In addition to the puzzle of how dust is made in the early universe, these results give us new clues to mysteries about how the Large Magellanic Cloud and even our own Milky Way became so dusty."

Previous studies had turned up some evidence that supernovae are capable of producing dust. For example, NASA's Spitzer Space Telescope, which detects shorter infrared wavelengths than Herschel, found 10,000 Earth-masses worth of fresh dust around the supernova remnant called Cassiopea A. Hershel can see even colder material, and thus the coldest reservoirs of dust. "The discovery of up to 230,000 Earths worth of dust around SN 1987A is the best evidence yet that these monstrous blasts are indeed mighty dust makers," said Eli Dwek, a co-author at NASA Goddard Space Flight Center in Greenbelt, Md.

Other authors include M. Otsuka, J. Roman-Duval, K.S. Long and K.D. Gordon, Space Telescope Science Institute, Baltimore, Md.; B. Babler, University of Wisconsin, Madison; M.J. Barlow, University College London, United Kingdom; C. Engelbracht, K.A. Misselt and E. Montiel, University of Arizona, Tucson; K. Sandstrom, Max Planck Institut für Astronomie, Heidelberg, Germany; M. Lakićević and J.Th. van Loon, Keele University, United Kingdom; G. Sonneborn, Goddard Space Flight Center, Greenbelt, Md.; G.C. Clayton, Louisiana State University, Baton Rouge; P. Lundqvist, Stockholm, Sweden; T. Nozawa, University of Tokyo, Japan; S. Hony, K. Okumura and M. Sauvage, the French Alternative Energies and Atomic Energy Commission, France.

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Old 07-19-2011, 06:54 PM   #63
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NASA:
July 19, 2011
Twisted Tale of our Galaxy's Ring

New observations from the Herschel Space Observatory show a bizarre, twisted ring of dense gas at the center of our Milky Way galaxy. Only a few portions of the ring, which stretches across more than 600 light-years, were known before. Herschel's view reveals the entire ring for the first time, and a strange kink that has astronomers scratching their heads.

Click on images for details
The Case of the Warped Galactic Ring
The Milky Way's Twisted Ring (annotated)
In a strange twist of science, astronomers using the Herschel Space Observatory have discovered that a suspected ring at the center of our galaxy is warped for reasons they cannot explain.
Image credit: ESA/NASA/JPL-Caltech


"We have looked at this region at the center of the Milky Way many times before in the infrared," said Alberto Noriega-Crespo of NASA's Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. "But when we looked at the high-resolution images using Herschel’s sub-millimeter wavelengths, the presence of a ring is quite clear." Noriega-Crespo is co-author of a new paper on the ring published in a recent issue of Astrophysical Journal Letters.

The Herschel Space Observatory is a European Space Agency-led mission with important NASA contributions. It sees infrared and sub-millimeter light, which can readily penetrate through the dust hovering between the bustling center of our galaxy and us. Herschel's detectors are also suited to see the coldest stuff in our galaxy.

When astronomers turned the giant telescope to look at the center of our galaxy, it captured unprecedented views of its inner ring -- a dense tube of cold gas mixed with dust, where new stars are forming.

Astronomers were shocked by what they saw -- the ring, which is in the plane of our galaxy, looked more like an infinity symbol with two lobes pointing to the side. In fact, they later determined the ring was torqued in the middle, so it only appears to have two lobes. To picture the structure, imagine holding a stiff, elliptical band and twisting the ends in opposite directions, so that one side comes up a bit.

"This is what is so exciting about launching a new space telescope like Herschel," said Sergio Molinari of the Institute of Space Physics in Rome, Italy, lead author of the new paper. "We have a new and exciting mystery on our hands, right at the center of our own galaxy."

Observations with the ground-based Nobeyama Radio Observatory in Japan complemented the Herschel results by determining the velocity of the denser gas in the ring. The radio results demonstrate that the ring is moving together as a unit, at the same speed relative to the rest of the galaxy.

The ring lies at the center of our Milky Way's bar -- a bar-shaped region of stars at the center of its spidery spiral arms. This bar is actually inside an even larger ring. Other galaxies have similar bars and rings. A classic example of a ring inside a bar is in the galaxy NGC 1097, imaged here by NASA's Spitzer Space Telescope. The ring glows brightly in the center of the galaxy's large bar structure. It is not known if that ring has a kink or not.

The details of how bars and rings form in spiral galaxies are not well understood, but computer simulations demonstrate how gravitational interactions can produce the structures. Some theories hold that bars arise out of gravitational interactions between galaxies. For example, the bar at the center of our Milky Way might have been influenced by our largest neighbor galaxy, Andromeda.

The twist in the ring is not the only mystery to come out of the new Herschel observations. Astronomers say that the center of the torqued portion of the ring is not where the center of the galaxy is thought to be, but slightly offset. The center of our galaxy is considered to be around "Sagittarius A*," where a massive black hole lies. According to Noriega-Crespo, it's not clear why the center of the ring doesn't match up with the assumed center of our galaxy. "There's still so much about our galaxy to discover," he said.

An abstract and full PDF of the Astrophysical Journal Letters study is online at http://arxiv.org/abs/1105.5486.

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Old 07-19-2011, 09:34 PM   #64
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Fascinating, look like a Moebious loop.

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Old 07-26-2011, 09:55 AM   #65
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ESA: Enceladus rains water onto Saturn:
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26 July 2011
ESA’s Herschel space observatory has shown that water expelled from the moon Enceladus forms a giant torus of water vapour around Saturn. The discovery solves a 14-year mystery by identifying the source of the water in Saturn’s upper atmosphere.

Herschel’s latest results mean that Enceladus is the only moon in the Solar System known to influence the chemical composition of its parent planet.

Enceladus expels around 250 kg of water vapour every second, through a collection of jets from the south polar region known as the Tiger Stripes because of their distinctive surface markings.

These crucial observations reveal that the water creates a doughnut-shaped torus of vapour surrounding the ringed planet.

The total width of the torus is more than 10 times the radius of Saturn, yet it is only about one Saturn radius thick. Enceladus orbits the planet at a distance of about four Saturn radii, replenishing the torus with its jets of water.

Despite its enormous size, it has escaped detection until now because water vapour is transparent to visible light but not at the infrared wavelengths Herschel was designed to see.

{...}

“ESA’s Infrared Space Observatory found the water vapour in Saturn’s atmosphere. Then NASA/ESA’s Cassini/Huygens mission found the jets of Enceladus. Now Herschel has shown how to fit all these observations together.”

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Old 08-01-2011, 05:30 PM   #66
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http://sci.esa.int/science-e/www/obj...objectid=49008

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Herschel uncovers 'hidden' oxygen in Orion
01 Aug 2011

Herschel has found the first robust evidence of molecular oxygen in the Orion Nebula. The observed abundance is ten times larger than indicated by previous observations of other molecular clouds, but is still well below theoretical expectations. The results suggest that, in special circumstances, the heat from newborn stars can liberate oxygen frozen out on dust grains, thus increasing the amount of molecular oxygen able to form in warm, dense gas clouds.
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Old 08-01-2011, 05:47 PM   #67
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NASA / NASA JPL:
Herschel Telescope Detects Oxygen Molecules in Space

August 01, 2011

PASADENA, Calif. – The Herschel Space Observatory's large telescope and state-of-the-art infrared detectors have provided the first confirmed finding of oxygen molecules in space. The molecules were discovered in the Orion star-forming complex.

Click on images for details
Herschel found oxygen molecules in a dense patch of gas and dust adjacent to star-forming regions in the Orion nebula.
Image credit: ESA/NASA/JPL-Caltech
The squiggly lines, or spectra, reveal the signatures of oxygen molecules, detected in the Orion nebula by the Hershel Space Observatory.
Image credit: ESA/NASA/JPL-Caltech


Individual atoms of oxygen are common in space, particularly around massive stars. But molecular oxygen, which makes up about 20 percent of the air we breathe, has eluded astronomers until now.

"Oxygen gas was discovered in the 1770s, but it's taken us more than 230 years to finally say with certainty that this very simple molecule exists in space," said Paul Goldsmith, NASA's Herschel project scientist at the agency's Jet Propulsion Laboratory in Pasadena, Calif. Goldsmith is lead author of a recent paper describing the findings in the Astrophysical Journal. Herschel is a European Space Agency-led mission with important NASA contributions.

Astronomers searched for the elusive molecules in space for decades using balloons, as well as ground- and space-based telescopes. The Swedish Odin telescope spotted the molecule in 2007, but the sighting could not be confirmed.

Goldsmith and his colleagues propose that oxygen is locked up in water ice that coats tiny dust grains. They think the oxygen detected by Herschel in the Orion nebula was formed after starlight warmed the icy grains, releasing water, which was converted into oxygen molecules.

"This explains where some of the oxygen might be hiding," said Goldsmith. "But we didn't find large amounts of it, and still don't understand what is so special about the spots where we find it. The universe still holds many secrets."

The researchers plan to continue their hunt for oxygen molecules in other star-forming regions.

"Oxygen is the third most common element in the universe and its molecular form must be abundant in space," said Bill Danchi, Herschel program scientist at NASA Headquarters in Washington. "Herschel is proving a powerful tool to probe this unsolved mystery. The observatory gives astronomers an innovative tool to look at a whole new set of wavelengths where the tell-tale signature of oxygen may be hiding."

{...}




NASA Press Release: RELEASE : 11-252 - Herschel Telescope Detects Oxygen Molecules In Space

SPACE.com: Oxygen Molecules Discovered in Deep Space for First Time
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Old 09-13-2011, 02:02 PM   #68
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ESA:
Herschel paints new story of galaxy evolution

13 September 2011

ESA's Herschel infrared space observatory has discovered that galaxies do not need to collide with each other to drive vigorous star birth. The finding overturns this long-held assumption and paints a more stately picture of how galaxies evolve.

Click on image to enlarge
A galaxy accretes mass from rapid, narrow streams of cold gas. These filaments provide the galaxy with continuous flows of raw material to feed its star-forming at a rather leisurely pace.
This theoretical scenario for galaxy formation is based on the numerical simulations presented by Dekel et al., 2009 (Nature, 457, 451D). However, the actual process of stream accretion onto a galaxy has never been directly observed and it remains speculative.
Credits: ESA–AOES Medialab


The conclusion is based on Herschel's observations of two patches of sky, each about a third of the size of the full Moon.

It's like looking through a keyhole across the Universe – Herschel has seen more than a thousand galaxies at a variety of distances from the Earth, spanning 80% of the age of the cosmos.

These observations are unique because Herschel can study a wide range of infrared light and reveal a more complete picture of star birth than ever seen before.

Click on images to enlarge
GOODS-North is a patch of sky in the northern hemisphere that covers an area of about a third the size of the Full Moon. This images was taken by Herschel at the following infrared wavelengths: 100μm (blue), 160μm (green) and 250μm (red). North is up and East is left.
Credits: ESA/GOODS-Herschel consortium/David Elbaz
GOODS-South is a patch of sky in the southern hemisphere that covers an area of about a third the size of the Full Moon. This images was taken by Herschel and NASA's Spitzer space telescope at the following infrared wavelengths:24 μm (blue), 100 μm (green) and 160 μm (red). North is up and East is left.
Credits: ESA/GOODS-Herschel consortium/NASA/JPL-Caltech/David Elbaz


It has been known for some years that the rate of star formation peaked in the early Universe, about 10 billion years ago. Back then, some galaxies were forming stars ten or even a hundred times more vigorously than is happening in our Galaxy today.

In the nearby, present-day Universe, such high birth rates are very rare and always seem to be triggered by galaxies colliding with each other. So, astronomers had assumed that this was true throughout history.

Herschel now shows that this is not the case by looking at galaxies that are very far away and thus seen as they were billions of years ago.

David Elbaz, CEA Saclay, France, and collaborators have analysed the Herschel data and find that galaxy collisions played only a minor role in triggering star births in the past, even though some young galaxies were creating stars at furious rates.

By comparing the amount of infrared light released at different wavelengths by these galaxies, the team has shown that the star birth rate depends on the quantity of gas they contain, not whether they are colliding.

Gas is the raw building material for stars and this work reveals a simple link: the more gas a galaxy contains, the more stars are born.

"It's only in those galaxies that do not already have a lot of gas that collisions are needed to provide the gas and trigger high rates of star formation", says Dr Elbaz.

This applies to today's galaxies because, after forming stars for more than 10 billion years, they have used up most of their gaseous raw material.

The research paints a much more stately picture of star births than before, with most galaxies sitting in space, growing slowly and naturally from the gas they attract from their surroundings.

"Herschel was conceived to study the history of star formation across cosmic time", says Göran Pilbratt, ESA Herschel Project Scientist.

"These new observations now change our perception of the history of the Universe."

{...}




NASA: Herschel Mission Finds Galactic Growth Slow and Steady
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Old 10-06-2011, 08:20 AM   #69
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H is still at it:

http://www.bbc.co.uk/news/science-environment-15181123

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Comet Hartley 2 contains water more like that found on Earth than prior comets seem to have, researchers say.

A study using the Herschel space telescope aimed to measure the quantity of deuterium, a rare type of hydrogen, present in the comet's water.

Like our oceans, it had half the amount of deuterium seen in other comets.
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Old 10-20-2011, 08:00 PM   #70
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NASA / NASA JPL:
Herschel Finds Oceans of Water in Disk of Nearby Star

October 20, 2011

PASADENA, Calif. -- Using data from the Herschel Space Observatory, astronomers have detected for the first time cold water vapor enveloping a dusty disk around a young star. The findings suggest that this disk, which is poised to develop into a solar system, contains great quantities of water, suggesting that water-covered planets like Earth may be common in the universe. Herschel is a European Space Agency mission with important NASA contributions.

Click on images for details
This artist's concept illustrates an icy planet-forming disk around a young star called TW Hydrae, located about 175 light-years away in the Hydra, or Sea Serpent, constellation.
Image credit: NASA/JPL-Caltech
This graph of data from Herschel shows how the cool water vapor was detected.
Image credit: ESA/NASA/JPL-Caltech/Leiden Observatory


Scientists previously found warm water vapor in planet-forming disks close to a central star. Evidence for vast quantities of water extending out into the cooler, far reaches of disks where comets take shape had not been seen until now. The more water available in disks for icy comets to form, the greater the chances that large amounts eventually will reach new planets through impacts.

"Our observations of this cold vapor indicate enough water exists in the disk to fill thousands of Earth oceans," said astronomer Michiel Hogerheijde of Leiden Observatory in The Netherlands. Hogerheijde is the lead author of a paper describing these findings in the Oct. 21 issue of the journal Science.

The star with this waterlogged disk, called TW Hydrae, is 10 million years old and located about 175 light-years away from Earth, in the constellation Hydra. The frigid, watery haze detected by Hogerheijde and his team is thought to originate from ice-coated grains of dust near the disk's surface. Ultraviolet light from the star causes some water molecules to break free of this ice, creating a thin layer of gas with a light signature detected by Herschel's Heterodyne Instrument for the Far-Infrared, or HIFI.

"These are the most sensitive HIFI observations to date," said Paul Goldsmith, NASA project scientist for the Herschel Space Observatory at the agency's Jet Propulsion Laboratory in Pasadena, Calif. "It is a testament to the instrument builders that such weak signals can be detected."

TW Hydrae is an orange dwarf star, somewhat smaller and cooler than our yellow-white sun. The giant disk of material that encircles the star has a size nearly 200 times the distance between Earth and the sun. Over the next few million years, astronomers believe matter within the disk will collide and grow into planets, asteroids and other cosmic bodies. Dust and ice particles will assemble as comets.

As the new solar system evolves, icy comets are likely to deposit much of the water they contain on freshly created worlds through impacts, giving rise to oceans. Astronomers believe TW Hydrae and its icy disk may be representative of many other young star systems, providing new insights on how planets with abundant water could form throughout the universe.

{...}




ESA: Herschel detects abundant water in planet-forming disc

NASA Press Release: RELEASE : 11-355 - Herschel Space Observatory Finds Oceans of Water in Planet-Forming Disk Around Nearby Star

Universe Today: Herschel Observatory Detects ‘Oceans’ of Water Around Distant Star
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Old 01-13-2012, 04:53 PM   #71
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One of Europe's great astronomical ventures is coming to a close.

The Planck telescope, put in space to map the oldest light in the Universe, has run out of the helium coolant that keeps it in full working order.
http://www.bbc.co.uk/news/science-environment-12065464
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Old 01-16-2012, 03:49 PM   #72
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ESA: Planck's HFI completes its survey of early Universe:
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16 January 2012

The High Frequency Instrument on ESA's Planck mission has completed its survey of the remnant light from the Big Bang. The sensor ran out of coolant on Saturday as expected, ending its ability to detect this faint energy.

"Planck has been a wonderful mission; spacecraft and instruments have been performing outstandingly well, creating a treasure trove of scientific data for us to work with," said Jan Tauber, ESA's Planck Project Scientist.

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Old 01-18-2012, 08:53 AM   #73
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NASA: Planck Telescope Warms up as Planned / NASA JPL
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Old 02-13-2012, 12:47 PM   #74
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ESA
Planck steps closer to the cosmic blueprint

13 February 2012

ESA’s Planck mission has revealed that our Galaxy contains previously undiscovered islands of cold gas and a mysterious haze of microwaves. These results give scientists new treasure to mine and take them closer to revealing the blueprint of cosmic structure.

The new results are being presented this week at an international conference in Bologna, Italy, where astronomers from around the world are discussing the mission’s intermediate results.

These results include the first map of carbon monoxide to cover the entire sky. Carbon monoxide is a constituent of the cold clouds that populate the Milky Way and other galaxies. Predominantly made of hydrogen molecules, these clouds provide the reservoirs from which stars are born.

However, hydrogen molecules are difficult to detect because they do not readily emit radiation. Carbon monoxide forms under similar conditions and, even though it is much rarer, it emits light more readily and therefore is more easily detectable. So, astronomers use it to trace the clouds of hydrogen.

Click on image to enlarge
This all-sky image shows the distribution of carbon monoxide (CO), a molecule used by astronomers to trace molecular clouds across the sky, as seen by Planck (blue). A compilation of previous surveys (Dame et al. (2001)), which left large areas of the sky unobserved, has been superimposed for comparison (red). The outlines identify the portions of the sky covered by these surveys.
Credits: ESA/Planck Collaboration; T. Dame et al., 2001


“Planck turns out to be an excellent detector of carbon monoxide across the entire sky,” says Planck collaborator Jonathan Aumont from the Institut d’Astrophysique Spatiale, Universite Paris XI, Orsay, France.

Surveys of carbon monoxide undertaken with radio telescopes on the ground are extremely time consuming, hence they are limited to portions of the sky where molecular clouds are already known or expected to exist.

Click on images to enlarge
This image shows the Cepheus molecular cloud complex as seen through the glow of carbon monoxide (CO) with Planck (blue). The same region is shown as imaged by previous CO surveys (Dame et al., 2001) for comparison (red).
Credits: ESA/Planck Collaboration; T. Dame et al., 2001
This image shows the Taurus molecular cloud complex as seen through the glow of carbon monoxide (CO) with Planck (blue). The same region is shown as imaged by previous CO surveys (Dame et al., 2001) for comparison (red).
Credits: ESA/Planck Collaboration; T. Dame et al., 2001


“The great advantage of Planck is that it scans the whole sky, allowing us to detect concentrations of molecular gas where we didn’t expect to find them,” says Dr Aumont.

Planck has also detected a mysterious haze of microwaves that presently defies explanation.

It comes from the region surrounding the galactic centre and looks like a form of energy called synchrotron emission. This is produced when electrons pass through magnetic fields after having been accelerated by supernova explosions.

Click on image to enlarge
This all-sky image shows the distribution of carbon monoxide (CO), a molecule used by astronomers to trace molecular clouds across the sky, as seen by Planck. The inserts provide a zoomed-in view onto three individual regions on the sky where Planck has detected concentrations of CO: Cepheus, Taurus and Pegasus, respectively.
Credits: ESA/Planck Collaboration


The curiosity is that the synchrotron emission associated with the galactic haze exhibits different characteristics from the synchrotron emission seen elsewhere in the Milky Way.

Click on image to enlarge
This all-sky image shows the spatial distribution over the whole sky of the Galactic Haze at 30 and 44 GHz, extracted from the Planck observations. In addition to this component, other foreground components such as synchrotron and free-free radiation, thermal dust, spinning dust, and extragalactic point sources contribute to the total emission detected by Planck at these frequencies. The prominent empty band across the plane of the Galaxy corresponds to the mask that has been used in the analysis of the data to exclude regions with strong foreground contamination due to the Galaxy's diffuse emission. The mask also includes strong point-like sources located over the whole sky.
Credits: ESA/Planck Collaboration


The galactic haze shows what astronomers call a ‘harder’ spectrum: its emission does not decline as rapidly with increasing energies.

Several explanations have been proposed for this unusual behaviour, including higher supernova rates, galactic winds and even the annihilation of dark-matter particles.

Click on image to enlarge
This all-sky image shows the distribution of the Galactic Haze seen by ESA's Planck mission at microwave frequencies superimposed over the high-energy sky as seen by NASA's Fermi Gamma-ray Space Telescope. The Planck data (shown here in red and yellow) correspond to the Haze emission at frequencies of 30 and 44 GHz, extending from and around the Galactic Centre. The Fermi data (shown here in blue) correspond to observations performed at energies between 10 and 100 GeV and reveal two bubble-shaped, gamma-ray emitting structures extending from the Galactic Centre.
Credits: ESA/Planck Collaboration (microwave); NASA/DOE/Fermi LAT/D. Finkbeiner et al. (gamma rays)


So far, none of them has been confirmed and it remains puzzling.

“The results achieved thus far by Planck on the galactic haze and on the carbon monoxide distribution provide us with a fresh view on some interesting processes taking place in our Galaxy,” says Jan Tauber, ESA’s Project Scientist for Planck.

Click on image to enlarge
This all-sky image shows the distribution of carbon monoxide (CO), a molecule used by astronomers to trace molecular clouds across the sky, as seen by Planck (blue). A compilation of previous surveys (Dame et al. (2001)), which left large areas of the sky unobserved, is shown for comparison (red).
Credits: ESA/Planck Collaboration; T. Dame et al., 2001


Planck’s primary goal is to observe the Cosmic Microwave Background (CMB), the relic radiation from the Big Bang, and to measure its encoded information about the constituents of the Universe and the origin of cosmic structure.

But it can only be reached once all sources of foreground emission, such as the galactic haze and the carbon monoxide signals, have been identified and removed.

Click on image to enlarge
This all-sky image shows the distribution of carbon monoxide (CO), a molecule used by astronomers to trace molecular clouds across the sky, as seen by Planck.
Credits: ESA/Planck Collaboration


“The lengthy and delicate task of foreground removal provides us with prime datasets that are shedding new light on hot topics in galactic and extragalactic astronomy alike,” says Dr Tauber.

“We look forward to characterising all foregrounds and then being able to reveal the CMB in unprecedented detail.”

Click on image to enlarge
This image shows molecular clouds in the Pegasus region as seen through the glow of carbon monoxide (CO) with Planck (blue).
Credits: ESA/Planck Collaboration


Planck’s first cosmological dataset is expected to be released in 2013.

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NASA / NASA JPL: Planck All-Sky Images Show Cold Gas and Strange Haze

Discovery News: Milky Way Humming with Microwave Mystery
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Old 02-19-2012, 08:52 AM   #75
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http://www.bbc.co.uk/news/science-environment-17087434

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Herschel, Europe's billion-euro space observatory, has entered what is likely to be its last year of operation.

The telescope studies the formation of stars, and has taken some remarkable pictures since its launch in May 2009.

But its detectors require a constant supply of superfluid helium to keep working, and the store of this coolant has now dropped to less than 100kg.

This past week saw Herschel begin what engineers believe will be the final 365 days of its mission life.
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