Tag: forming (page 2 of 6)

Far Flung Star Cluster Found at Milky Way’s Edge

Astronomers in Brazil have discovered a cluster of stars forming at the edge of the Milky Way, according to a press release from the Royal Astronomical Society.




Excerpt from  news.discovery.com


This is unusual because it was believed that stars generally take form closer to the center of our spiral-shaped galaxy, rather than from its swirling, spiral arms, which are thousands of light-years away. These two clusters of stars — named Camargo 438 and 439 — were seen in a cloud at the galaxy’s outskirts.

Denilso Camargo, an astronomer at the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, led a team that analyzed data from NASA’s orbiting Wide-Field Infrared Survey Explorer (WISE) observatory. They zeroed in on dense clumps of gas in so-called giant molecular clouds(GMCs) that are known to generate stars. GMCs are mainly located in the inner part of the galactic disc.

The new star clusters lie about 16,000 light-years away from the main disk of the Milky Way galaxy. How did they form there? The scientists aren’t yet sure but Camargo theorizes that one of two scenarios could have led to the stars’ formation.

In the first scenario, called the “chimney model,” supernovas could have flung the gas and dust that formed the cloud out of the Milky Way. Another explanation is the material could have drifted in from outside the galaxy.


“Our work shows that the space around the Galaxy is a lot less empty that we thought,” said Camargo. “The new clusters of stars are truly exotic.”

Camargo’s team published their results in the journal Monthly

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Is This a Baby Picture of a Giant Planet?


Hubble optical image (left) and VLT infrared image (right) of the circumstellar disk surrounding HD 100546. (ESO/NASA/ESA/Ardila et al.)


Excerpt from news.discovery.com


Mommy, where do baby planets come from? There’s no storks, birds, bees, or romantic dinners for two involved in the answer to that question — regardless of size, planets are all formed in pretty much the same way: through the aggregation of material within the disk of dust and gas surrounding a young star. While how long it actually takes and just what sort of planets are most likely to form where are still topics of discussion among astronomers, the birth process of a planet is fairly well understood.

And this may be the very first image of it actually happening.

Acquired by the European Southern Observatory’s Very Large Telescope (VLT), the infrared image above (right) shows a portion of the disk of gas and dust around the star HD100546, located 335 light-years away in the constellation Musca. By physically blocking out the light from the star itself by means of an opaque screen — seen along the left side of the image — the light from the protoplanetary disk around HD 100546 can be seen, revealing a large bright clump that’s thought to be a planet in the process of formation.

If it is indeed a baby planet, it’s a big one — as large as, or perhaps even larger than, Jupiter.

A candidate protoplanet found in a disc of gas and dust around young star HD100546 (ESO)


This does raise an interesting question for astronomers because if it is a Jupiter-sized planet, it’s awfully far from its star… at least according to many current models of planetary formation. About 68 times as far from HD100546 as we are from the sun, if this planet were in our solar system it’d be located deep in the Kuiper Belt, twice as far as Pluto. That’s not where one would typically expect to find gas giants, so it’s been hypothesized that this protoplanet might have migrated outwards after initially forming closer to the star… perhaps “kicked out” by gravitational interaction with an even more massive planet.

Alternatively, it may not be a planet at all — the bright blob in the VLT image might be coming from a much more distant source. While extremely unlikely, further research will be needed to rule that possibility out.

If it’s found to be a planet, HD100546 “b” would offer scientists an unprecedented opportunity to observe a planetary formation process in action — and from a relatively close proximity as well.

According to the team’s paper, submitted to Astrophysical Journal Letters, ”What makes HD100546 particularly interesting is that 1. it would be the first imaged protoplanet that is still embedded in the gas and dust disk of its host star; and 2. it would show that planet formation does occur at large orbital separations.”

(Now all we have to do is wait a couple billion years and then show these pictures to HD100546b’s girlfriend. How embarrassing!)

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NASA creates ingredients of life in harsh simulated space conditions


The machine NASA scientists used to zap out three components of our hereditary material from a chunk of ice.


Excerpt from cnet.com

We know a whole lot about life on our planet, but one mystery persists: how it got here.

NASA scientists working at the Ames Astrochemistry Laboratory in California and the Goddard Space Flight Center in Maryland may have just found a clue to that mystery. They've determined that some of the chemical components of our DNA can be produced in the harsh crucible of space.


To reach their conclusion, they created a chunk of ice in their lab containing molecules known as pyrimidine. These molecules, which consist of carbon and nitrogen, form the core of three chemicals found in DNA and RNA, the genetic composition of all Earth-based life.

Pyrimidine is also found on meteorites, which prompted the researchers to explore how it reacts when frozen in water in space.
So they put their chunk of ice in a machine that reproduces the vacuum of space, along with temperatures around -430°F and harsh radiation created by high-energy ultraviolet (UV) photons from a hydrogen lamp.

They found that not only could the pyrimidine molecules survive these brutal conditions, but the radiation actually morphed some of them into three chemical components found in DNA and RNA: uracil, cytosine and thymine. 

"We are trying to address the mechanisms in space that are forming these molecules," Christopher Materese, a NASA researcher working on these experiments, said in a statement. "Considering what we produced in the laboratory, the chemistry of ice exposed to ultraviolet radiation may be an important linking step between what goes on in space and what fell to Earth early in its development."
Added Scott Sandford, a space science researcher at Ames, "Our experiments suggest that once the Earth formed, many of the building blocks of life were likely present from the beginning. Since we are simulating universal astrophysical conditions, the same is likely wherever planets are formed."

While this research might help fill in a piece of the puzzle of our cosmic origins, another mystery remains. Scientists don't exactly know where meteoric pyrimidine comes from in the first place, although they theorize that it could arise when giant red stars die. And the search continues...

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Earth’s Moon May Not Be Critical to Life Afterall




Excerpt from space.com

The moon has long been viewed as a crucial component in creating an environment suitable for the evolution of complex life on Earth, but a number of scientific results in recent years have shown that perhaps our planet doesn't need the moon as much as we have thought.

In 1993, French astronomer Jacques Laskar ran a series of calculations indicating that the gravity of the moon is vital to stabilizing the tilt of our planet. Earth's obliquity, as this tilt is technically known as, has huge repercussions for climate. Laskar argued that should Earth's obliquity wander over hundreds of thousands of years, it would cause environmental chaos by creating a climate too variable for complex life to develop in relative peace.
So his argument goes, we should feel remarkably lucky to have such a large moon on our doorstep, as no other terrestrial planet in our solar system has such a moon. Mars' two satellites, Phobos and Deimos, are tiny, captured asteroids that have little known effect on the Red Planet. Consequently, Mars' tilt wobbles chaotically over timescales of millions of years, with evidence for swings in its rotational axis at least as large as 45 degrees. 


The stroke of good fortune that led to Earth possessing an unlikely moon, specifically the collision 4.5 billion years ago between Earth and a Mars-sized proto-planet that produced the debris from which our Moon formed, has become one of the central tenets of the 'Rare Earth' hypothesis. Famously promoted by Peter Ward and Don Brownlee, it argues that planets where everything is just right for complex life are exceedingly rare.

New findings, however, are tearing up the old rule book. In 2011, a trio of scientists — Jack Lissauer of NASA Ames Research Center, Jason Barnes of the University of Idaho and John Chambers of the Carnegie Institution for Science — published results from new simulations describing what Earth's obliquity would be like without the moon. What they found was surprising.

"We were looking into how obliquity might vary for all sorts of planetary systems," says Lissauer. "To test our code we began with integrations following the obliquity of Mars and found similar results to other people. But when we did the obliquity of Earth we found the variations were much smaller than expected — nowhere near as extreme as previous calculations suggested they would be."
Lissauer's team found that without the moon, Earth's rotational axis would only wobble by 10 degrees more than its present day angle of 23.5 degrees. The reason for such vastly different results to those attained by Jacques Laskar is pure computing power. Today's computers are much faster and capable of more accurate modeling with far more data than computers of the 1990s.

Lissauer and his colleagues also found that if Earth were spinning fast, with one day lasting less than 10 hours, or rotating retrograde (i.e. backwards so that the sun rose in the West and set in the East), then Earth stabilized itself thanks to the gravitational resonances with other planets, most notably giant Jupiter. There would be no need for a large moon. 

Earth's rotation has not always been as leisurely as the current 24 hour spin-rate. Following the impact that formed the moon, Earth was spinning once every four or five hours, but it has since gradually slowed by the moon's presence. As for the length of Earth's day prior to the moon-forming impact, nobody really knows, but some models of the impact developed by Robin Canup of the Southwest Research Institute, in Boulder, Colorado, suggest that Earth could have been rotating fast, or even retrograde, prior to the collision.

Tilted Orbits
Planets with inclined orbits could find that their increased obliquity is beneficial to their long-term climate – as long as they do not have a large moon.


"Collisions in the epoch during which Earth was formed determined its initial rotation," says Lissauer. "For rocky planets, some of the models say most of them will be prograde, but others say comparable numbers of planets will be prograde and retrograde. Certainly, retrograde worlds are not expected to be rare."

The upshot of Lissauer's findings is that the presence of a moon is not the be all and end all as once thought, and a terrestrial planet can exist without a large moon and still retain its habitability. Indeed, it is possible to imagine some circumstances where having a large moon would actually be pretty bad for life.

Rory Barnes, of the University of Washington, has also tackled the problem of obliquity, but from a different perspective. Planets on the edge of habitable zones exist in a precarious position, far enough away from their star that, without a thick, insulating atmosphere, they freeze over, just like Mars. Barnes and his colleagues including John Armstrong of Weber State University, realized that torques from other nearby worlds could cause a planet's inclination to the ecliptic plane to vary. This in turn would result in a change of obliquity; the greater the inclination, the greater the obliquity to the Sun. Barnes and Armstrong saw that this could be a good thing for planets on the edges of habitable zones, allowing heat to be distributed evenly over geological timescales and preventing "Snowball Earth" scenarios. They called these worlds "tilt-a-worlds," but the presence of a large moon would counteract this beneficial obliquity change.

"I think one of the most important points from our tilt-a-world paper is that at the outer edge of the habitable zone, having a large moon is bad, there's no other way to look at it," says Barnes. "If you have a large moon that stabilizes the obliquity then you have a tendency to completely freeze over."

Barnes is impressed with the work of Lissauer's team.
"I think it is a well done study," he says. "It suggests that Earth does not need the moon to have a relatively stable climate. I don't think there would be any dire consequences to not having a moon."

Mars' Changing Tilt
The effects of changing obliquity on Mars’ climate. Mars’ current 25-degree tilt is seen at top left. At top right is a Mars that has a high obliquity, leading to ice gather at its equator while the poles point sunwards. At bottom is Mars with low obliquity, which sees its polar caps grow in size.


Of course, the moon does have a hand in other factors important to life besides planetary obliquity. Tidal pools may have been the point of origin of life on Earth. Although the moon produces the largest tides, the sun also influences tides, so the lack of a large moon is not necessarily a stumbling block. Some animals have also evolved a life cycle based on the cycle of the moon, but that's more happenstance than an essential component for life.

"Those are just minor things," says Lissauer.

Without the absolute need for a moon, astrobiologists seeking life and habitable worlds elsewhere face new opportunities. Maybe Earth, with its giant moon, is actually the oddball amongst habitable planets. Rory Barnes certainly doesn't think we need it.
"It will be a step forward to see the myth that a habitable planet needs a large moon dispelled," he says, to which Lissauer agrees.
Earth without its moon might therefore remain habitable, but we should still cherish its friendly presence. After all, would Beethoven have written the Moonlight Sonata without it?

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ALMA uncovers stellar nurseries in the Sculptor Galaxy, 11.5 million light years from home



ALMA uncovers stellar nurseries in the Sculptor Galaxy, 11.5 million light years from home
The Sculptor Galaxy


Excerpt from sciencerecorder.com

Starburst galaxies are named for their ability to convert gasses rapidly into new stars, at an accelerated speed that can sometimes be 1,000 times more rapid than your average spiral galaxy, such as the Milky Way. Why the disparity? In order to further investigate the reason that some galaxies seem to “burst” into being, whereas others take the better part of a few billion years, an international team of astronomers analyzed a cluster of star-forming gas clouds in the heart of NGC 253 – the Sculptor Galaxy, with the aid of the Atacama Large Millimeter/submillimeter Array (ALMA). The Sculptor Galaxy is among starburst galaxies closest to the Milky Way.

“All stars form in dense clouds of dust and gas,” said Adam Leroy, in an interview with Astronomy magazine. Leroy is an astronomer at Ohio State University in Columbus. “Until now, however, scientists struggled to see exactly what was going on inside starburst galaxies that distinguished them from other star-forming regions.”

Therefore, Leroy and his colleagues turn to the ALMA which is capable of examining star changing structures even in systems as distant as Sculptor. Already, they have successfully charted distribution and movement of various molecules within several clouds located at the Sculptor Galaxy’s core.


Because NGC 253, which is disk-shaped, is in the stages of a very intense starburst and located approximately 11.5 million light-years from home, it is the perfect target for study. ALMA picks it up with remarkable precision and resolution, so much so that the team was able to isolate and identify ten different stellar ‘nurseries,’ in which stars were in the process of forming. To appreciate the magnitude of this feat, it would have been impossible with previous telescopes, which blurred the regions together into one glow. 

“There is a class of galaxies and parts of galaxies, we call them starbursts, where we know that gas is just plain better at forming stars,” said Leroy. “To understand why, we took one of the nearest such regions and pulled it apart — layer by layer — to see what makes the gas in these places so much more efficient at star formation.”


More importantly, they recognized the distribution of several 40 millimeter-wavelength “signatures,” that given off by various molecules at the center of Sculptor Galaxy, signaling that a number of conditions were responsible for the development of these stars. This accounts for the diversity of the states of different stars corresponding to where they are found in star-forming clouds. One important compound, all too familiar and unwelcome on Earth, carbon monoxide (CO), correlates with massive envelopes of gases that are less dense within the stellar nurseries. Others, such as hydrogen cyanide (HCN), were present in the more dense reaches of active star formation. The rarer the molecules, for example, H13CN and H13CO+, suggest regions that are even denser.


Indeed, when the data was compared, researchers found that the gas clouds of the Sculptor Galaxy were ten times denser than those found in spiral galaxies, suggesting that because the clouds are so tightly packed, they can form star clusters much more rapidly than the Milky Way. At the same time, they give us further insight as to how stars are born, showing us the physical changes along the way, allowing astronomers a working model to compare with our own galaxy. 


“These differences have wide-ranging implications for how galaxies grow and evolve,” concluded Leroy. “What we would ultimately like to know is whether a starburst like Sculptor produces not just more stars, but different types of stars than a galaxy like the Milky Way. ALMA is bringing us much closer to that goal.”

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NASA Wants to Send a Submarine to Titan’s Seas ~ Video



Titan


Excerpt from news.discovery.com

In a sneak peek of a possible future mission to Saturn’s moon Titan, NASA has showcased their vision of a robotic submersible that could explore the moon’s vast lakes of liquid methane and ethane.

Studying Titan is thought to be looking back in time at an embryonic Earth, only a lot colder. Titan is the only moon in the solar system to have a significant atmosphere and this atmosphere is known to possess its own methane cycle, like Earth’s water cycle. Methane exists in a liquid state, raining down on a landscape laced with hydrocarbons, forming rivers, valleys and seas.

Several seas have been extensively studied by NASA’s Cassini spacecraft during multiple flybys, some of which average a few meters deep, whereas others have depths of over 200 meters (660 feet) — the maximum depth at which Cassini’s radar instrument can penetrate.


So, if scientists are to properly explore Titan, they must find a way to dive into these seas to reveal their secrets.

At this year’s Innovative Advanced Concepts (NIAC) Symposium, a Titan submarine concept was showcased by NASA Glenn’s COMPASS Team and researchers from Applied Research Lab.

Envisaged as a possible mission to Titan’s largest sea, Kracken Mare, the autonomous submersible would be designed to make a 90 day, 2,000 kilometer (1,250 mile) voyage exploring the depths of this vast and very alien marine environment. As it would spend long periods under the methane sea’s surface, it would have to be powered by a radioisotope generator; a source that converts the heat produced by radioactive pellets into electricity, much like missions that are currently exploring space, like Cassini and Mars rover Curiosity.

Communicating with Earth would not be possible when the vehicle is submerged, so it would need to make regular ascents to the surface to transmit science data.

But Kracken Mare is not a tranquil lake fit for gentle sailing — it is known to have choppy waves and there is evidence of tides, all contributing to the challenge. Many of the engineering challenges have already been encountered when designing terrestrial submarines — robotic and crewed — but as these seas will be extremely cold (estimated to be close to the freezing point of methane, 90 Kelvin or -298 degrees Fahrenheit), a special piston-driven propulsion system will need to be developed and a nitrogen will be needed as ballast, for example.

This study is just that, a study, but the possibility of sending a submersible robot to another world would be as unprecedented as it is awesome.

Although it’s not clear at this early stage what the mission science would focus on, it would be interesting to sample the chemicals at different depths of Kracken Mare.

“Measurement of the trace organic components of the sea, which perhaps may exhibit prebiotic chemical evolution, will be an important objective, and a benthic sampler (a robotic grabber to sample sediment) would acquire and analyze sediment from the seabed,” the authors write (PDF). “These measurements, and seafloor morphology via sidescan sonar, may shed light on the historical cycles of filling and drying of Titan’s seas. Models suggest Titan’s active hydrological cycle may cause the north part of Kraken to be ‘fresher’ (more methane-rich) than the south, and the submarine’s long traverse will explore these composition variations.”

A decade after the European Huygens probe landed on the surface of Titan imaging the moon’s eerily foggy atmosphere, there have been few plans to go back to this tantalizing world. It would be incredible if, in the next few decades, we could send a mission back to Titan to directly sample what is at the bottom of its seas, exploring a region where the molecules for life’s chemistry may be found in abundance.



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How Would the World Change If We Found Alien Life?







Excerpt from space.com
By by Elizabeth Howell

In 1938, Orson Welles narrated a radio broadcast of "War of the Worlds" as a series of simulated radio bulletins of what was happening in real time as Martians arrived on our home planet. The broadcast is widely remembered for creating public panic, although to what extent is hotly debated today.

Still, the incident serves as an illustration of what could happen when the first life beyond Earth is discovered. While scientists might be excited by the prospect, introducing the public, politicians and interest groups to the idea could take some time.

How extraterrestrial life would change our world view is a research interest of Steven Dick, who just completed a term as the Baruch S. Blumberg NASA/Library of Congress Chair of Astrobiology. The chair is jointly sponsored by the NASA Astrobiology Program and the John W. Kluge Center, at the Library of Congress. 


Dick is a former astronomer and historian at the United States Naval Observatory, a past chief historian for NASA, and has published several books concerning the discovery of life beyond Earth. To Dick, even the discovery of microbes would be a profound shift for science.

"If we found microbes, it would have an effect on science, especially biology, by universalizing biology," he said. "We only have one case of biology on Earth. It's all related. It's all DNA-based. If we found an independent example on Mars or Europa, we have a chance of forming a universal biology."

Dick points out that even the possibilities of extraterrestrial fossils could change our viewpoints, such as the ongoing discussion of ALH84001, a Martian meteorite found in Antarctica that erupted into public consciousness in 1996 after a Science article said structures inside of it could be linked to biological activity. The conclusion, which is still debated today, led to congressional hearings.

"I've done a book about discovery in astronomy, and it's an extended process," Dick pointed out. "It's not like you point your telescope and say, 'Oh, I made a discovery.' It's always an extended process: You have to detect something, you have to interpret it, and it takes a long time to understand it. As for extraterrestrial life, the Mars rock showed it could take an extended period of years to understand it."


ALH84001 Meteorite
The ALH84001 meteorite, which in a 1996 Science publication was speculated to be host to what could be ancient Martian fossils. That finding is still under dispute today.

Mayan decipherments

In his year at the Library of Congress, Dick spent time searching for historical examples (as well as historical analogies) of how humanity might deal with first contact with an extraterrestrial civilization. History shows that contact with new cultures can go in vastly different directions.

Hernan Cortes' treatment of the Aztecs is often cited as an example of how wrong first contact can go. But there were other efforts that were a little more mutually beneficial, although the outcomes were never perfect. Fur traders in Canada in the 1800s worked closely with Native Americans, for example, and the Chinese treasure fleet of the 15th Century successfully brought its home culture far beyond its borders, perhaps even to East Africa.

Even when both sides were trying hard to make communication work, there were barriers, noted Dick.

"The Jesuits had contact with Native Americans," he pointed out. "Certain concepts were difficult, like when they tried to get across the ideas of the soul and immortality."



A second look by the Mars Global Surveyor at the so-called Viking “Face on Mars” in Cydonia revealed a more ordinary-looking hill, showing that science is an extended process of discovery.


Indirect contact by way of radio communications through the Search for Extraterrestrial Intelligence (SETI), also illustrates the challenges of transmitting information across cultures. There is historical precedence for this, such as when Greek knowledge passed west through Arab translators in the 12th Century. This shows that it is possible for ideas to be revived, even from dead cultures, he said.

It's also quite possible that the language we receive across these indirect communications would be foreign to us. Even though mathematics is often cited as a universal language, Dick said there are actually two schools of thought. One theory is that there is, indeed, one kind of mathematics that is based on a Platonic idea, and the other theory is that mathematics is a construction of the culture that you are in. 

"There will be a decipherment process. It might be more like the Mayan decipherments," Dick said.


The ethics of contact

As Dick came to a greater understanding about the potential c impact of extraterrestrial intelligence, he invited other scholars to present their findings along with him. Dick chaired a two-day NASA/Library of Congress Astrobiology Symposium called "Preparing for Discovery," which was intended to address the impact of finding any kind of life beyond Earth, whether microbial or some kind of intelligent, multicellular life form.

The symposium participants discussed how to move beyond human-centered views of defining life, how to understand the philosophical and theological problems a discovery would bring, and how to help the public understand the implications of a discovery.

"There is also the question of what I call astro-ethics," Dick said. "How do you treat alien life? How do you treat it differently, ranging from microbes to intelligence? So we had a philosopher at our symposium talking about the moral status of non-human organisms, talking in relation to animals on Earth and what their status is in relation to us."

Dick plans to collect the lectures in a book for publication next year, but he also spent his time at the library gathering materials for a second book about how discovering life beyond Earth will revolutionize our thinking.

"It's very farsighted for NASA to fund a position like this," Dick added. "They have all their programs in astrobiology, they fund the scientists, but here they fund somebody to think about what the implications might be. It's a good idea to do this, to foresee what might happen before it occurs."

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Neptune-Like Planets Could Transfom Into Habitable Worlds

Strong irradiation from the host star can cause planets known as mini-Neptunes in the habitable zone to shed their gaseous envelopes and become potentially habitable worlds.Credit: Rodrigo Luger / NASA imagesExcerpt from sciencedaily.com Two ph...

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Move Over Hubble, Meet the New High Powered Star Searcher


NASA'S James Webb Space Telescope


Excerpt from space.com


NASA's James Webb Space Telescope, scheduled for launch in 2018, will probe the cosmos to uncover the history of the universe from the Big Bang to alien planet formation and beyond.
Scientists are planning to use the infrared telescope to search for the first galaxies that formed at the beginning of the universe. The James Webb Space Telescope (JWST) will also have the ability to look through cosmic dust clouds to find newly forming planetary systems and seek out the chemical origins of life in the solar system.

The powerful $8.8 billion spacecraft is also expected to take amazing photos of celestial objects like its predecessor, the Hubble Space Telescope. 


Instruments on board

The JWST will come equipped with four science instruments.
  • Near-Infrared Camera (NIRCam) — Provided by the University of Arizona, this infrared camera will detect light from stars in nearby galaxies and stars within the Milky Way. It will also search for light from stars and galaxies that formed early in the universe's life. NIRCam will be outfitted with coronagraphs that can block a bright object's light, making dimmer objects near those stars (like planets) visible.
  • Near-Infrared Spectrograph (NIRSpec) — NIRSpec will observe 100 objects simultaneously, searching for the first galaxies that formed after the Big Bang. NIRSpec was provided by the European Space Agency with help from NASA's Goddard Space Flight Center.
  • Mid-Infrared Instrument (MIRI) — MIRI will produce amazing space photos of distant celestial objects, following in Hubble's tradition of astrophotography. The spectrograph that is a part of the instrument will allow scientists to gather more physical details about distant objects in the universe. MIRI will detect distant galaxies, faint comets, forming stars and objects in the Kuiper Belt. MIRI was built by the European Consortium with the European Space Agency and NASA's Jet Propulsion Laboratory.
  • Fine Guidance Sensor/Near InfraRed Imager and Slitless Spectrograph (FGS/NIRISS) — This Canadian Space Agency-built instrument is more like two instruments in one. The FGS component is responsible for keeping the JWST pointed in exactly the right direction during its science investigations. NIRISS will scope out the cosmos to find signatures of the first light in the universe and seek out and characterize alien planets.
The telescope will also sport a tennis court-size sunshield and a 21.3 foot (6.5 meter) mirror — the largest mirror ever launched into space. Those components will not fit into the rocket launching the JWST, so both will unfurl once the telescope is in space.

Infrared: Inside the huge space observatory that operates from a point in space four times further away than the moon.
NASA's James Webb Space Telescope is an $8.8 billion space observatory built to observe the infrared universe like never before. See how NASA's James Webb Space Telescope works in this Space.com infographic
James Webb the man

The JWST is named for former NASA chief James Webb. Webb took charge of the space agency from 1961 to 1968, retiring just a few months before NASA put the first man on the moon.

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The (Not So) Curious Case of Galaxy IC 335

This odd-looking galaxy has recently become famous in the media, not for what it has but for what is missing!Excerpt from huffingtonpost.comA recent Hubble image of this galaxy shows it to be a star-filled galaxy with a flat shape not unlike our own M...

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Giant Dunes on Saturn’s Moon Titan





Excerpt from space.com

The towering dunes on Saturn's largest moon, Titan, may look similar to the sandy hills of Earth's Sahara, but their origins are completely different, researchers say. Instead of forming continuously over time like on Earth, Titans dunes are forged by short, powerful rogue winds.

Reaching heights of more than 300 feet (91 meters), the dunes of Titan present a puzzling mystery: they seem to form in the opposite direction as Titan's steady east-to-west winds. Two new studies suggest that rare bursts of wind blowing westward are responsible for these enormous structures. The findings shed light on the remote satellite that shares many qualities with Earth.

"It was a bear to operate, but Dr. Burr's refurbishment of the facility as a Titan simulator has tamed the beast. It is now an important addition to NASA's arsenal of planetary simulation facilities," John Marshall, of the SETI Institute, and a co-author on the new research, said in the statement.

Titan's dunes are not made of the kind of sand found in deserts on Earth, but a more viscous material. Scientists don't know exactly what it is, only that it is made of hydrogen and carbon — two ingredients that can be used to create a laundry list of different materials on Earth, from methane to paraffin wax. According to Burr, the hydrogen-carbon material may coat particles of water ice.
The researchers found that the regular east-to-west winds are not strong enough to shape the viscous material into the massive dune shapes that are observed. Instead, they believe the dunes are shaped by short, rapid bursts of westerly wind. The winds on Titan "occasionally reverse direction and dramatically increase in intensity due to the changing position of the Sun in its sky," the statement said.

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New Geologic Map Shows the Beauty of the Asteroid Vesta


This new map of the asteroid Vesta, which uses a Mollweide projection, reveals the asteroid's geological history.
This new map of Vesta, which uses a Mollweide projection, reveals the asteroid’s geological history. NASA/JPL-Caltech/Arizona State University



Excerpt from 
wired.com


For 15 months between 2011 and 2012, the Dawn spacecraft orbited the asteroid called Vesta, snapping high-resolution pictures of the cratered, potato-shaped rock. Scientists then spent another two and a half years poring over the images and piecing together the geology written on Vesta’s surface. Now, a team led by planetary scientist David Williams of Arizona State University has compiled that information together into this beautiful map, which they’ve published online for the December issue of the journal Icarus.

Vesta was forged within the cloud of dust and debris that formed the solar system about 4.5 billion years ago. During its lifetime, Vesta was pelted with smaller asteroids and rocks, which left a multitude of craters. But according to the researchers, there were three impacts in particular that shaped Vesta’s geological history. The most recent collision happened sometime between 120 million and 390 million years ago, forming the Marcia crater seen near the center of the map.

Two earlier impacts struck Vesta’s south pole more than one billion years ago between 200 million and one billion years apart, making the Veneneia and Rheasilvia craters, which are each about 300 miles in diameter. These collisions were so big that they reshaped the asteroid, leading to its elongated shape today, Williams says. 

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Magnetic Fields of an Ancient Meteorite Give Clues to the Formation of Our Universe


Ancient meteorite's magnetic fields gives clues to the formation of the universe
Photo courtesy of Mila Zinkova


Excerpt from
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A better understanding of how the universe was formed comes from what is left of a meteorite. The meteorite is named Semarkona, and it touched down in India in the 1940′s. Arizona State University’s School of Earth and Space Exploration wanted to measure the magnetic levels of the meteorite, and in doing so, they have shown we are closer to understanding how the solar system was formed.

It would seem rather insignificant given its size of just one and a half pounds, but it was formed over four and a half billion years ago. Researchers admit the magnetic flux of the rock mimics the magnetic forces here on the planet.

Every magnetic fluctuation of Semarkona has been mapped and the fluctuations of the magnetic field recorded in a study that is the first of its kind. This has given researchers more insight into the magnetic fields that were pivotal in forming the universe.

The study, aptly named Solar nebula magnetic fields recorded in the Semarkona meteorite was published in the November 13 issue of the journal Science.

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