A Ring Nebula around Wolf-Rayet Star

Made with narrow and broad band filters, this colourful cosmic snap shot covers a field of view about the size of the full Moon within the boundaries of the constellation Cygnus.

It highlights the bright edge of a ring-like nebula traced by the glow of ionized hydrogen and oxygen gas.

Embedded in the region's interstellar clouds of gas and dust, the complex, glowing arcs are sections of bubbles or shells of material swept up by the wind from Wolf-Rayet star WR 134, brightest star near the center of the frame.

Distance estimates put WR 134 about 6,000 light-years away, making the frame over 50 light-years across.

Shedding their outer envelopes in powerful stellar winds, massive Wolf-Rayet stars have burned through their nuclear fuel at a prodigious rate and end this final phase of massive star evolution in a spectacular supernova explosion.

The stellar winds and final supernovae enrich the interstellar material with heavy elements to be incorporated in future generations of stars.

JCMT: The first detailed image of filamentary structure in Orion A cloud

The first detailed image of filamentary structure traced in the Northern part of the Orion A cloud, showing where the stars are forming from clumps of cold gas and dust. 

The ability to image condensations of cold dust with the earlier SCUBA camera, and more recently with SCUBA-2, has made the JCMT one of the choice instruments in the world for studying the earliest stages of star formation.

Credit: Johnstone et al.

NASA MARS: Dusty Rover Opprtunity's Self Portrait

This self portrait from NASA's Mars Exploration Rover Opportunity shows dust accumulation on the rover's solar panels as the mission approached its fifth Martian winter.

The dust reduces the rover's power supply, and the rover's mobility is limited until the winter is over or wind cleans the panels.

This is a mosaic of images taken by Opportunity's panoramic camera (Pancam) during the 2,111th to 2,814th Martian days, or sols, of the rover's mission (Dec. 21 to Dec. 24, 2011).

The downward-looking view omits the mast on which the camera is mounted.

The portrait is presented in approximate true colour, the camera team's best estimate of what the scene would look like if humans were there and able to see it with their own eyes.

Opportunity has worked through four Martian southern hemisphere winters since it landed in in January 2004 about 14 miles (23 kilometers) northwest of its current location.

Closer to the equator than its twin rover, Spirit, Opportunity has not needed to stay on a sun-facing slope during the previous winters.

Now, however, Opportunity's solar panels carry a thicker coating of dust, and the team is using a strategy employed for three winters with Spirit: staying on a sun-facing slope.

The sun will pass relatively low in the northern sky from the rover's perspective for several months of shortened daylight before and after the southern Mars winter solstice on March 30, 2012.

Opportunity is conducting research while located on the north-facing slope of a site called "Greeley Haven."

Image Credit: NASA/JPL-Caltech/Cornell/Arizona State Univ.

NASA Cassini: Flaring fairy lights of Saturn's F ring

One of Saturn's rings is flaring and fading in a very strange fashion.

When Voyager 1 visited the planet in 1980, the ring was faint, but it sparkled with bright spots.

By the time the Cassini mission arrived in 2004, the spots were gone – but the ring as a whole had grown twice as bright.

Saturn's F ring has been a puzzle since it was discovered by the Pioneer 11 spacecraft in 1979.

While most of the inner rings have clear, well-defined edges, the F ring, which is the outermost of Saturn's main rings, has a thin central core surrounded by a diffuse skirt of smoke-sized ice particles.

That swirl of smoke forms kinks and knots, and some of it winds around the ring's core in a spiral.

Most of these funny features can be blamed on the little moon Prometheus, which orbits just inside the F ring.

As its elliptical orbit brings Prometheus towards and away from the ring on a 17-year cycle, the moon contorts the ring with its gravity.

It even steals material from the ring when it comes too close, as its mythical namesake stole fire from the gods.

"We knew the F ring changed on a day to day and even hour to hour basis because of interactions with Prometheus," says Robert French, a research assistant at the SETI Institute in Mountain View, California.

"But people always assumed it was stable over the longer term, over decades if not millennia."

So French and colleagues got a surprise when they compared images from the Voyager 1 and 2 missions, which zipped past Saturn in 1980 and 1981, with images from the Cassini spacecraft, which has been orbiting the planet since July 2004.

They found that the ring was twice as bright in 2004 as it was in 1980. It had also grown three times as wide and twice as opaque.

"All of that means there's a lot more dust today than there used to be," French says. Those tiny particles scatter sunlight, so when there are more of them the whole ring shines more brightly.

French's first thought was to blame Prometheus. But while Prometheus's orbit brought it closer to the F ring over the first 5 years of Cassini's stay in the Saturn system, the ring didn't change.

"That's very puzzling," French says. "People usually think of Prometheus as the cause of changes in the F ring, and Prometheus was making large changes in how it interacted with the F ring. Yet the F ring wasn't changing."

Carina Nebula: Delayed Broadcast of Powerful Stellar Eruption

These images reveal light from a massive stellar outburst in the Carina Nebula reflecting off dust clouds surrounding a behemoth double-star system.

The colour image at left shows the Carina Nebula, a star-forming region located 7,500 light-years from Earth.

The massive double-star system Eta Carinae resides near the top of the image.

The star system, about 120 times more massive than the Sun, produced a spectacular outburst that was seen on Earth from 1837 to 1858. But some of the light from the eruption took an indirect path and is just now reaching our planet.

The light bounced off dust clouds (the boxed region about 100 light-years away at the bottom of the image) and was rerouted to Earth, a phenomenon called a light echo. The image was taken in February 2000 by the U.S. National Optical Astronomy Observatory's Curtis Schmidt Telescope at the Cerro Tololo Inter-American Observatory (CTIO) in Chile.

The three black-and-white images at right show light from the eruption illuminating dust clouds near the doomed star system as it moves through them. The effect is like shining a flashlight on different regions of a vast cavern.

The images were taken over an eight-year span by the U.S. National Optical Astronomy Observatory's Blanco 4-meter telescope at the CTIO.

Credit: NASA, NOAO, and A. Rest (Space Telescope Science Institute, Baltimore, Md.)

NASA WISE Image: Cosmic clouds bubbling with new star birth

A new, large mosaic from NASA's Wide-Field Infrared Survey Explorer (WISE) showcases a vast stretch of cosmic clouds bubbling with new star birth.

The region - a 1,000-square-degree chunk of our Milky Way galaxy - is home to numerous star-forming clouds, where massive stars have blown out bubbles in the gas and dust.

"Massive stars sweep up and destroy their natal clouds, but they continuously spark new stars to form along the way," said WISE Mission Scientist Dave Leisawitz of NASA Goddard Space Flight Center, Greenbelt, Md. Leisawitz is co-author of a new paper reporting the results in the Astrophysical Journal.

"Occasionally a new, massive star forms, perpetuating the sequence of events and giving rise to the dazzling fireworks display seen in this WISE mosaic."

The WISE space telescope mapped the entire sky two times in infrared light, completing its survey in February of 2011. Astronomers studying how stars form took advantage of WISE's all-encompassing view by studying several star-forming clouds, or nebulae, including 10 pictured in this new view.

The observations provide new evidence for a process called triggered star formation, in which the winds and sizzling radiation from massive stars compress gas and dust, inducing a second generation of stars. The same winds and radiation carve out the cavities, or bubbles, seen throughout the image.

Finding evidence for triggered star formation has proved more difficult than some might think. Astronomers are not able to watch the stars grow and evolve like biologists watching zebras in the wild.

Instead, they piece together a history of star formation by looking at distinct stages in the process. It's the equivalent of observing only baby, middle-aged and elderly zebras with crude indicators of their ages. WISE is helping to fill in these gaps by providing more and more "specimens" for study.

"Each region we looked at gave us a single snapshot of star formation in progress," said Xavier Koenig, lead author of the new study at Goddard, who presented the results in Austin, Texas, at the 219th meeting of the American Astronomical Society. "But when we look at a whole collection of regions, we can piece together the chain of events."

After looking at several of the star-forming nebulae, Koenig and his colleagues noticed a pattern in the spatial arrangement of newborn stars. Some were found lining the blown-out cavities, a phenomenon that had been seen before, but other new stars were seen sprinkled throughout the cavity interiors.

The results suggest that stars are born in a successive fashion, one after the other, starting from a core cluster of massive stars and moving steadily outward. This lends support to the triggered star formation theory, and offers new clues about the physics of the process.

The astronomers also found evidence that the bubbles seen in the star-forming clouds can spawn new bubbles. In this scenario, a massive star blasts away surrounding material, eventually triggering the birth of another star massive enough to carve out its own bubble. A few examples of what may be first- and second-generation bubbles can be seen in the new WISE image.

"I can almost hear the stars pop and crackle," said Leisawitz.

Subaru Telescope Confirms Signs of Unseen Planets in Dust Ring of HR 4796 A

Near-infrared (1.6 micron) image of the debris ring around the star HR 4796 A.

An astronomical unit (AU) is a unit of length that corresponds to the average distance between the Earth and Sun, almost 92 million miles (over 149 million km).

The ring consists of dust grains in a wide orbit (roughly twice the size of Pluto's orbit) around the central star.

Its edge is so precisely revealed that the researchers could confirm a previously suspected offset between the ring's center and the star's location.

This "wobble" in the dust's orbit is most likely caused by the unbalancing action of, so far undetected, massive planets likely to be orbiting within the ring.

Furthermore, the image of the ring appears to be smudged out at its tips and reveals the presence of finer dust extending out beyond the main body of the ring.

The SEEDS (Strategic Exploration of Exoplanets and Disks with Subaru Telescope/HiCIAO) project, a five-year international collaboration launched in 2009 and led by Motohide Tamura of NAOJ (National Astronomical Observatory of Japan) has yielded another impressive image that contributes to our understanding of the link between disks and planet formation.

Researchers used Subaru's planet-finder camera, HiCIAO (High Contrast Instrument for the Subaru Next Generation Adaptive Optics), to take a crisp high-contrast image of the dust ring around HR 4796 A, a young (8-10 million years old) nearby star, only 240 light years away from Earth.

The ring consists of dust grains in a wide orbit, roughly twice the size of Pluto's orbit, around the central star.

The resolution of the image of the inner edge of the ring is so precise that an offset between its center and the star's position can be measured.

Although data from the Hubble Space Telescope led another research group to suspect such an offset, the Subaru data not only confirm its presence but also reveal it to be larger than previously assumed.

ESA NASA Hubble telescope image: Elliptical Galaxy

This diffuse-looking galaxy may be the only evidence remaining from an ancient collision between two galaxies.

Known as SDSS J162702.56+432833.9, this object is technically catalogued as an elliptical galaxy, but it was likely created during the collision of two spiral galaxies, astronomers say.

This image was taken by the Hubble Space Telescope. Some ribbons of dust notably obscure parts of the conglomerated galaxy's central, bluish region. Those dust lanes could be remnants of the spiral arms of the recently departed galaxies.

Stunning Photo of Beta Pictoris Galaxy by Amateur Astronomer

An amateur astronomer captured the shot of his life when he took a picture of forming solar system.

Auckland resident Rolf Olsen is the first amateur astronomer to take pictures of another solar system from his small telescope in his backyard.

Olsen managed to photograph the star Beta Pictoris, which is located 60 light years away.

He only used a 25 cm telescope to capture the image of the distant galaxy.

Beta Pictoris is estimated to be about 12 million years old and is considered a model for what the Milky Way looked like 4.5 billion years ago. It had been previously been photographed by the Hubble Space Telescope.

In the 1980s infrared images of the galaxy revealed that it's surrounded by a flat dust disk. The disk is larger than our solar system and scientists have wanted to capture a picture of it for further study. The only problem is that the star is so bright that it can obscure the dust disk around it.

Rolf managed to get rid of the unwanted light to get a clear picture of Beta Pictoris with the dust disk surrounding it.

Rolf got the idea from an 18-year-old scientific paper from Harvard tiled "Observation of the central part of the beta Pictoris disk with an anti-blooming CCD" that describes how to get an image using similar equipment.

First he took pictures of Beta Pictoris using a camera mounted on his telescope. He then took another batch of pictures of another star, Alpha Pictoris which is similar to Beta Pictoris in brightness and color.

He subtracted the image of the second star to eliminate the glare from Beta Pictoris. Rolf cleaned up the raw subtracted image to make the dust disk easier to see. The result is a clear image of Beta Pictoris with the dust disk surrounding it.

"And the result is, I believe, the first amateur image of another solar system: The protoplanetary disc around Beta Pictoris. I must say it feels really special to have actually captured this," Olsen writes in his website.

The scientific community has been quick to laud Olsen's effort.

NASA: Comet Elenin Gone and Should Be Forgotten

Comet Elenin is no more. Latest indications are this relatively small comet has broken into even smaller, even less significant, chunks of dust and ice.

This trail of piffling particles will remain on the same path as the original comet, completing its unexceptional swing through the inner solar system this fall.

"Elenin did as new comets passing close by the sun do about two percent of the time: It broke apart," said Don Yeomans of NASA's Near-Earth Object Program Office in Pasadena, Calif.

"Elenin's remnants will also act as other broken-up comets act. They will trail along in a debris cloud that will follow a well-understood path out of the inner solar system.

After that, we won't see the scraps of comet Elenin around these parts for almost 12 millennia."

Twelve millennia may be a long time to Earthlings, but for those frozen inhabitants of the outer solar system who make this commute, a dozen millennia give or take is a walk in the celestial park.

Comet Elenin came as close as 45 million miles (72 million kilometers) to the sun, but it arrived from the outer solar system's Oort Cloud, which is so far away its outer edge is about a third of the way to the nearest star other than our sun.

For those broken up over the breakup of what was formerly about 1.2 miles (two kilometers) of uninspiring dust and ice, remember what Yeomans said about comets coming close to the sun - they fall apart about two percent of the time.

"Comets are made up of ice, rock, dust and organic compounds and can be several miles in diameter, but they are fragile and loosely held together like dust balls," said Yeomans.

"So it doesn't take much to get a comet to disintegrate, and with comets, once they break up, there is no hope of reconciliation."

Comet Elenin first came to light last December, when sunlight reflecting off the small comet was detected by Russian astronomer Leonid Elenin of Lyubertsy, Russia.

Hawaii Astronomers Find Planet in the Process of Forming

Artist's conception of the area near the planet LkCa 15 b. Click on picture for larger view. Credit: Karen L. Teramura, UH IfA.

The first direct image of a planet in the process of forming around its star has been captured by University of Hawaii astronomer Adam Kraus.

What astronomers are calling LkCa 15 b, looks like a hot "protoplanet" surrounded by a swath of cooler dust and gas, which is falling into the still-forming planet.

Images have revealed that the forming planet sits inside a wide gap between the young parent star and an outer disk of dust.

Kraus (UH Institute for Astronomy) and colleague Michael Ireland (Macquarie University and the Australian Astronomical Observatory) combined the power of the 10-meter Keck Observatory telescopes with a bit of optical sleight of hand.

"LkCa 15 b is the youngest planet ever found, about 5 times younger than the previous record holder," said Kraus.

"This young gas giant is being built out of the dust and gas. In the past, you couldn't measure this kind of phenomenon because it's happening so close to the star. But, for the first time, we've been able to directly measure the planet itself as well as the dusty matter around it."

Kraus will be presenting the discovery at an Oct. 19 meeting at NASA's Goddard Space Flight Center. The meeting follows the acceptance of a research paper on the discovery by Kraus and Ireland by The Astrophysical Journal.

The optical sleight of hand used by the astronomers is to combine the power of Keck's Adaptive Optics with a technique called aperture mask interferometry. The former is the use of a deformable mirror to rapidly correct for atmospheric distortions of starlight.

The latter involves placing a small mask with several holes in the path of the light collected and concentrated by a giant telescope. With that, the scientists can manipulate the light waves.

"It's like we have an array of small mirrors," said Kraus. "We can manipulate the light and cancel out distortions." The technique allows the astronomers to cancel out the bright light of stars. They can then resolve disks of dust around stars and see gaps in the dusty layers where protoplanets may be hiding.

"Interferometry has actually been around since the 1800s, but through the use of adaptive optics has only been able to reach nearby young suns for about the last 7 years." said Dr. Ireland.

"Since then we've been trying to push the technique to its limits using the biggest telescopes in the world, especially Keck."

The discovery of LkCa 15 b began as a survey of 150 young dusty stars in star-forming regions. That led to the more concentrated study of a dozen stars.

"LkCa 15 was only our second target, and we immediately knew we were seeing something new," said Kraus. "We could see a faint point source near the star, so thinking it might be a Jupiter-like planet we went back a year later to get more data."

Formation of Scheila's Triple Dust Tails Explained

Optical images of Scheila at three different epochs with different telescopes.

Images of the triple dust tails were taken on the 12th and 19th of December 2010 using the Murikabushi Telescope. 

Bottom: Suprime-Cam on the Subaru Telescope captured this image of the linear structure on the 2nd of March 2011.

A research team of planetary scientists and astronomers, mainly from Seoul National University, the National Astronomical Observatory of Japan (NAOJ), the Institute of Space and Astronautical Science (ISAS), and Kobe University, has explained the formation of peculiar triple dust tails from the asteroid Scheila (asteroid #596).

The researchers concluded that another asteroid about 20-50 meters in size impacted Scheila from behind on December 3, 2010, and accounted for its unusual brightness and form.

On December 11.4, 2010, Steve Larson of the Catalina Sky Survey noticed an odd brightness from Scheila, an asteroid on the outer region of the main belt of asteroids that orbit in an area between Mars and Jupiter.

Three streams of dust appeared to trail from the asteroid. Data from NASA's Swift Satellite and the Hubble Space Telescope suggested that a smaller asteroid's impact was the likely trigger for the appearance of comet-like tails from Scheila.

However, questions remained about the date when the dust emission occurred and how the triple dust tails formed. The current research team sought answers to these queries.

Soon after reports of Scheila's unusual brightness, the current research team used the Subaru Prime Focus Camera (Suprime-Cam) on the Subaru Telescope (8.2 m), the Ishigakijima Astronomical Observatory Murikabushi Telescope (1.05 m), and the University of Hawaii 2.2 m Telescope to make optical observations of these mysterious dust tails over a three-month period.

The top of Figure 1 shows images of the development of the dust tails taken by the Murikabushi Telescope on the 12th and 19th of December 2010. Although asteroids generally look like points when observed from Earth, Scheila looked like a comet.

As the three streaks of dust streamed from the asteroid, their surface brightness decreased. Eventually the dust clouds became undetectable, and then a faint linear structure appeared.

The bottom of Figure 1 shows the image obtained by Subaru Telescope on March 2, 2011. Based on these images of the linear structure, the scientists determined a dust emission date of December 3.5+/-1, 2010. Steve Larson of the Catalina Sky Survey noticed that Scheila had a slightly diffuse appearance on December 3.4, 2010.

Therefore, it is likely that the collision of the asteroids occurred within the short time between December 2 12:00 UT and December 3 10:00 UT.

To explain the formation of Scheila's triple dust tails, the research team conducted a computer simulation of Scheila's dust emission on December 3th.

Their simulation was based on information gained through impact experiments in a laboratory at ISAS, a hypervelocity impact facility and division of the Japan Aerospace Exploration Agency (JAXA). Figure 2 shows the ejecta produced by an oblique impact, which was not a head-on collision.

Two prominent features characterize oblique impacts and the shock waves generated by them. One feature, a downrange plume, occurs in a direction downrange from the impact site and results from the fragmentation or sometimes evaporation of the object that impacted another.

A second feature occurs during the physical destruction of the impacted object; a shock wave spreads from the impact site, scoops out materials (conical impact ejecta), and forms an impact crater. The axis of the cone of ejecta is roughly perpendicular to the surface at the impact site.

The team reasoned that these two processes caused the ejection of Scheila's dust particles and that sunlight pushed them away from the asteroid. After performing a tremendous number of computer simulations under different conditions, they could only duplicate their observed images when an object struck Scheila's surface from behind (Figures 3 and 4).

Taking all of the evidence into account-their observations and simulations--the research team concluded that there is only one way to explain the mysterious brightness and triple tails of dust from Scheila. A smaller asteroid obliquely impacted Scheila from behind.

Spiral Arms Point to Possible Planets in a Star's Dusty Disk

Two spiral arms emerge from the gas-rich disk around SAO 206462, a young star in the constellation Lupus. 

This image, acquired by the Subaru Telescope and its HiCIAO instrument, is the first to show spiral arms in a circumstellar disk. 

The disk itself is some 14 billion miles across, or about twice the size of Pluto's orbit in our own solar system. (Credit: NAOJ/Subaru)

A new image of the disk of gas and dust around a sun-like star is the first to show spiral-arm-like structures.

These features may provide clues to the presence of embedded but as-yet-unseen planets.

"Detailed computer simulations have shown us that the gravitational pull of a planet inside a circumstellar disk can perturb gas and dust, creating spiral arms.

Now, for the first time, we're seeing these dynamical features," said Carol Grady, an astronomer with Eureka Scientific, Inc., who is based at NASA's Goddard Space Flight Center in Greenbelt, Md. Grady revealed the images at the Signposts of Planets meeting hosted this week at the center.

Grady's research is part of the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS), a five-year-long near-infrared study of young stars and their surrounding dust disks using the Subaru Telescope atop Mauna Kea in Hawaii.

The international consortium of researchers now includes more than 100 scientists at 25 institutions.

"What we're finding is that once these systems reach ages of a few million years, their disks begin to show a wealth of structure - rings, divots, gaps and now spiral features," said John Wisniewski, a collaborator at the University of Washington in Seattle.

"Many of these structures could be caused by planets within the disks."

The newly imaged disk surrounds SAO 206462, an 8.7-magnitude star located about 456 light-years away in the constellation Lupus. Astronomers estimate that the system is only about 9 million years old.

The gas-rich disk spans some 14 billion miles, which is more than twice the size of Pluto's orbit in our own solar system.

The Subaru near-infrared image reveals a pair of spiral features arcing along the outer disk. Theoretical models show that a single embedded planet may produce a spiral arm on each side of a disk.

The structures around SAO 206462 do not form a matched pair, suggesting the presence of two unseen worlds, one for each arm.

However, the research team cautions that processes unrelated to planets may give rise to these structures.

The view was made possible by the High Contrast Instrument for the Subaru Next Generation Adaptive Optics, or (HiCIAO, pronounced "HI-chow"), which is designed to block out harsh direct starlight.

'Pacman Nebula' Lives the High Life

High-mass stars are important because they are responsible for much of the energy pumped into our galaxy over its lifetime.

Unfortunately, these stars are poorly understood because they are often found relatively far away and can be obscured by gas and dust.

The star cluster NGC 281 is an exception to this rule.

It is located about 9,200 light years from Earth and, remarkably, almost 1,000 light years above the plane of the Galaxy, giving astronomers a nearly unfettered view of the star formation within it.

NGC 281 is known informally as the "Pacman Nebula" because of its appearance in optical images. In optical images the "mouth" of the Pacman character appears dark because of obscuration by dust and gas, but in the infrared Spitzer image the dust in this region glows brightly.

Image Credits: X-ray: NASA/CXC/CfA/S.Wolk; IR: NASA/JPL/CfA/S.Wolk

ESA ESO: Chicken space dust cloud

With bright glowing eyes and a swirl of crimson, the chicken concealed in the Lambda Centauri nebula looks ready to pummel some pigs in a game of Angry Birds.

The new shot from the European Southern Observatory shows hot newborn stars that formed from hydrogen gas clouds glowing brightly with ultraviolet light.

The intense radiation excites the hydrogen cloud, making it glow red.

Visible against the red clouds, black clumps called Bok globules dot the frame and conceal stars within.

Known playfully as the "running chicken" nebula, the bird's roost is some 6500 light years from Earth in the constellation Centaurus. But where does the chicken end? If you think you can make out its exact outline, submit your guess to the observatory's Flickr group for a chance at a prize.

ESA Herschel: Infrared radiation penetrating dust clouds

ESA’s Herschel infrared observatory has an unprecedented view on the cold universe, bridging the gap between what can be observed from the ground and earlier infrared space missions.

Infrared radiation can penetrate the gas and dust clouds that hide objects from optical telescopes, looking deep into star-forming regions, galactic centres and planetary systems.

Also cooler objects, such as tiny stars and molecular clouds, even galaxies enshrouded in dust that are barely emitting optical light, can be visible in the infrared.

Credits: ESA - C. Carreau

Read more here: ESA Herschel 

ESA Herschel: Exploding stars can make good dust factories

This mosaic shows the region surrounding the remnant of the famous supernova SN1987A as observed by Herschel (on the left) and the Hubble Space Telescope (on the right).

SN1987A exploded 24 years ago in the Large Magellanic Cloud, one of the dwarf galaxies orbiting the Milky Way.

At a distance of only 160,000 light years, this backyard supernova has become a 'local' laboratory for close-up studies of stellar demise.

The remnant of SN1987A is visible, in the Herschel image, as a faint dot of light indicated by the white circle; the region enclosed within the circle is shown in greater detail in the Hubble image.

The detection of SN1987A with Herschel demonstrates that this object contains an amount of dust nearly equivalent to the mass of the Sun and roughly 1000 times larger than what was previously believed.

At temperatures of 16–23 Kelvin, the newly discovered component is about 20 times colder than any dust detected in the past in this supernova remnant.

This result confirms that supernovae are able to produce significant quantities of dust over very short timescales and has profound implications on the understanding of how dust first formed in cosmic history.

Credits: ESA/Herschel/PACS/SPIRE/NASA-JPL/Caltech/UCL/STScI and the Hubble Heritage Team (AURA/STScI/NASA/ESA)

Read more here: ESA Herschel

Our Cruel Sun: Exposed Earth to Cosmic Rays

The sun protects the earth from cosmic rays and dust from the solar system but squeezing of various stars could leave us unprotected (Image: NASA/HST collection)

THE sun provides ideal conditions for life to thrive, right? In fact, it periodically leaves Earth open to assaults from interstellar nasties in a way that most stars do not.

The sun protects us from cosmic rays and dust from beyond the solar system by enveloping us in the heliosphere - a bubble of solar wind that extends past Pluto. These cosmic rays would damage the ozone layer, and interstellar dust could dim sunlight and trigger an ice age. However, when the solar system passes through very dense gas and dust clouds, the heliosphere can shrink until its edge is inside Earth's orbit.

In a paper to appear in Astrobiology, David Smith at the University of Arizona in Tucson and John Scalo at the University of Texas, Austin, calculated the squeezing of various stars' protective "astrospheres". They found Earth is exposed to between one and 10 interstellar assaults every billion years. Habitable planets around a red dwarf, which account for three of every four stars, are never exposed. That's because they need to be close to these dim stars to be warm enough to be habitable. "The bottom line is that habitable planets around red dwarfs are better protected from climate catastrophes than Earth is," says Smith.