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Author Topic: Science Photo of the Week  (Read 467954 times)

Offline neilep

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Some quality pics of the Antarctic here
http://www.leenks.com/link132921.html

I just looked at every single one !

Imposing and Sensational Photos !...I'd love to go there.
 

Offline rosalind dna

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Hubble Space Telescope Advent Calendar 2008, the Astronomical Photos are beautiful. I think.

http://www.boston.com/bigpicture/2008/12/hubble_space_telescope_advent.html






 

Offline elmejor

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"Residents of Tainan learned a lesson in whale biology after the decomposing remains of a 60-ton sperm whale exploded on a busy street, showering nearby cars and shops with blood and organs and stopping traffic for hours."

Source : MSNBC



Links : Naked Scientists Radio Show coverage of this story 1st February 2004 newbielink:http://www.thenakedscientists.com/html/shows/2004.02.01.htm [nonactive]


that must have been a stinky day for everybody around. well how did it explode?
 

Offline neilep

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18 Billion Suns -Biggest Black Hole in Universe Discovered—and it’s BIG! A Galaxy Classic





Whatever gave birth to this monster can be real proud. The biggest black hole in the universe weighs in with a respectable mass of 18 billion Suns, and is about the size of an entire galaxy. Just like in the Arnold Schwarzenegger and Danny Devito flick “Twins”, the massive black hole has a puny twin hovering nearby. By observing the orbit of the smaller black hole, astronomers are able to test Einstein's theory of general relativity with stronger gravitational fields than ever before.

The biggest black hole beats out its nearest competitor by six times. Fortunately, it’s 3.5 billion light years away, forming the heart of a quasar called OJ287. Quasars are extremely bright objects in which matter spiraling into a giant black hole emits large amounts of radiation.

The smaller black hole, which weighs about 100 million Suns, orbits the larger one on an oval-shaped path every 12 years. It comes close enough to punch through the disc of matter surrounding the larger black hole twice each orbit, causing a pair of outbursts that make OJ287 suddenly brighten.

General relativity predicts that the smaller hole's orbit itself should rotate over time, so that the point at which it comes nearest its neighbor moves around in space. This effect  is seen in Mercury's orbit around the Sun, on a much smaller scale.

In the case of OJ287, the tremendous gravitational field of the larger black hole causes the smaller black hole's orbit to precess at an impressive 39° each orbit. The precession changes where and when the smaller hole crashes through the disc surrounding its larger sibling.

About a dozen of the resulting bright outbursts have been observed to date, and astronomers led by Mauri Valtonen of Tuorla Observatory in Finland have analysed them to measure the precession rate of the smaller hole's orbit. That, along with the period of the orbit, suggests the larger black hole weighs a record 18 billion Suns.

So just how big can these bad boys get? Craig Wheeler of the University of Texas in Austin, US, says it depends only on how long a black hole has been around and how fast it has swallowed matter in order to grow. "There is no theoretical upper limit," he says.

The most recent outburst occurred on 13 September 2007, as predicted by general relativity. "If there was no orbital decay, the outburst would have been 20 days later than when it actually happened," Valtonen told New Scientist, adding that the black holes are on track to merge within 10,000 years.

Wheeler says the observations of the outbursts fit closely with the expectations from general relativity. "The fact that you can fit Einstein's theory [so well] ... is telling you that that's working," he says.


SOURCE:http://www.dailygalaxy.com
 

Offline neilep

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Dark energy’s galactic stranglehold seen


BY KULVINDER SINGH CHADHA

ASTRONOMY NOW


Posted: 19 December, 2008

It dominates the Universe, accounting for 74 percent of its energy density. The mysterious, space-stretching force known as dark energy, which is accelerating the expansion of the Universe, could also be inhibiting the development of galaxies.


In a study that has taken years to complete, astronomers using the Chandra X-ray Observatory have seen that something is stifling the growth of galaxy clusters. The crucial thing about Chandra’s data is that it is independent of previous dark energy studies that have made use of supernovae. It means that there is a real phenomenon occurring that isn’t an artefact of observational techniques. Research team leader Dr Alexey Vikhlinin of the Harvard-Smithsonian Astrophysical Observatory likens the effect to an ‘arrested development’ of the Universe.



Snapshots from a simulation representing the
growth of cosmic structure when the Universe
was 0.9, 3.2 and 13.7 billion years old (now)
, from a smooth state to one with structure.
 Image: MPE/V.Springel.


Dark energy is in competition with the gravitational force, because unlike gravity, dark energy is repulsive. Invisible dark matter, which is known to constitute around 95 percent of the Universe’s mass, is responsible for much of this gravity. But on the largest scales dark energy appears to win out, hence the observed acceleration of an already expanding Universe (something which was well-known). But why should this repulsion inhibit the growth of galaxy clusters, the most massive collapsed objects in the Universe?


At a NASA press conference on 16 December, Vikhlinin’s colleague Dr William Forman says, “Structures [galaxy clusters] grow from very weak fluctuations present in the beginning of the Universe, and which can be seen in the Cosmic Microwave Background radiation. Gravity slows the expansion of the Universe and amplifies these very small fluctuations so that they grow to form the galaxy clusters we see so prominently in the X-ray images.” Forman adds that the scale of the new observations is around 100 million light years. This is the scale where the effect of dark energy becomes important. When the Universe entered and accelerated expansion phase eight billion years ago, the dominance of dark energy slowed structure growth significantly.



Galaxy cluster Abell 85 is one of 86 clusters
 observed by Chandra to trace how dark energy
has stifled the growth of massive structures
over the last 7 billion years. Image:
 SDSS/NASA/CXC/SAO/A.Vikhlinin et al.



The reason that X-ray observations are used is because the bulk of the normal mass (i.e. not dark matter) of the cluster is in the form of high-temperature, diffuse, intergalactic gas. This is straightforward to see in X-rays and has the advantage of being bright, thus observable at great distances. And this property was particularly helpful to Vikhlinin’s team. By looking at galactic clusters at different distances, Vikhlin’s team were able to observe structure growth at different epochs of the Universe’s development. What they found corroborated well with accelerating and decelerating phases in the Universe’s history.


But this is just a tentative first step towards unravelling the mystery of dark energy. Its exact nature is still a matter of speculation. Could it be the famed cosmological constant predicted by Einstein (the inherent energy of space itself)? Or, does Einstein’s Theory of General Relativity, which describes gravitation, need to be revised on these large scales? Could it be something else entirely? Will we ever truly know?


Forman ends on an upbeat note, quoting American physicist John Wheeler: “Mass tells space how to curve, and space tells mass how to behave. With supernovae data, we’ve seen how mass curves space, and with our results, we can now see how space tells matter to behave.”

SOURCE:SPACEFLIGHTNOW.COM
 

Offline neilep

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Jupiter's largest moon caught going to 'dark side'
SPACE TELESCOPE SCIENCE INSTITUTE NEWS RELEASE


NASA's Hubble Space Telescope has caught Jupiter's moon Ganymede playing a game of "peek-a-boo." In this crisp Hubble image, Ganymede is shown just before it ducks behind the giant planet.


Credit: NASA, ESA, E. Karkoschka (University of Arizona)

 
 
Ganymede completes an orbit around Jupiter every seven days. Because Ganymede's orbit is tilted nearly edge-on to Earth, it routinely can be seen passing in front of and disappearing behind its giant host, only to reemerge later.

Composed of rock and ice, Ganymede is the largest moon in our solar system. It is even larger than the planet Mercury. But Ganymede looks like a dirty snowball next to Jupiter, the largest planet in our solar system. Jupiter is so big that only part of its Southern Hemisphere can be seen in this image.

Hubble's view is so sharp that astronomers can see features on Ganymede's surface, most notably the white impact crater, Tros, and its system of rays, bright streaks of material blasted from the crater. Tros and its ray system are roughly the width of Arizona.

The image also shows Jupiter's Great Red Spot, the large eye-shaped feature at upper left. A storm the size of two Earths, the Great Red Spot has been raging for more than 300 years. Hubble's sharp view of the gas giant planet also reveals the texture of the clouds in the Jovian atmosphere as well as various other storms and vortices.

Source:spaceflightnow.com
 

Offline neilep

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The Galactic Core in Infrared
Credit: Hubble: NASA, ESA, & D. Q. Wang (U. Mass, Amherst); Spitzer: NASA, JPL, & S. Stolovy (SSC/Caltech)




WOW !!..awesome big pig piccy right here !!



 What's happening at the center of our Milky Way Galaxy? To help find out, the orbiting Hubble and Spitzer space telescopes have combined their efforts to survey the region in unprecedented detail in infrared light. Infrared light is particularly useful for probing the Milky Way's center because visible light is more greatly obscured by dust. The above image encompasses over 2,000 images from the Hubble Space Telescope's NICMOS taken last year. The image spans 300 by 115 light years with such high resolution that structures only 20 times the size of our own Solar System are discernable. Clouds of glowing gas and dark dust as well as three large star clusters are visible. Magnetic fields may be channeling plasma along the upper left near the Arches Cluster, while energetic stellar winds are carving pillars near the Quintuplet Cluster on the lower left. The massive Central Cluster of stars surrounding Sagittarius A* is visible on the lower right. Why several central, bright, massive stars appear to be unassociated with these star clusters is not yet understood.
 

Offline neilep

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Orion's Belt
Credit & Copyright: Martin Mutti, Astronomical Image Data Archive




BIGGY PICCY HERE

Alnitak, Alnilam, and Mintaka, are the bright bluish stars from east to west (left to right) along the diagonal in this gorgeous cosmic vista. Otherwise known as the Belt of Orion, these three blue supergiant stars are hotter and much more massive than the Sun. They lie about 1,500 light-years away, born of Orion's well-studied interstellar clouds. In fact, clouds of gas and dust adrift in this region have intriguing and some surprisingly familiar shapes, including the dark Horsehead Nebula and Flame Nebula near Alnitak at the lower left. The famous Orion Nebula itself lies off the bottom of this star field that covers about 4.5x3.5 degrees on the sky. This image was taken last month with a digital camera attached to a small telescope in Switzerland, and better matches human color perception than a more detailed composite taken over 15 years ago.
 

Offline neilep

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Planck Probe To Record the Very Echoes of Creation



Blue Lagoon Nebula !




Probing the very earliest available evidence of the universe as we know it has already netted a Nobel Prize, but if you understand science at all you know that that's just the beginning.  In April the Planck satellite will start recording the very echoes of creation, and that's such a big picture the teams have spent ten years just getting ready to look at the data.

Huge statistical analysis at two data centers (one in Paris and one one in Trieste) are needed to extract information from the data the Planck will receive, and when they practice the take it seriously.  As in "The Max Planck institute spending a decade developing software to simulate virtual universes as test cases" serious, which is more seriously than a heart surgeon operating on his firstborn son.

These test cases are versions of the cosmic microwave background, the earliest available information in existence.  The universe is thought to have been around for a few hundred thousand years before that, but as it was opaque to radiation nothing survived to echo. Accurate information from the instant it all became transparent, expanding rapidly into the reality we now know (as far as we know now) could make or break many theories of how it all got going.

As well as studying the effects of inflation (or not) on the beginning of the universe, Plank will also gather data on "secondary anisotropies" - or as you might know them, galactic clusters.  This thing looks at a question so big, a trillion suns is a side-effect.
 

Offline neilep

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Parasitic wasps lay eggs in caterpillars using toxins to paralyze their hosts. The wasp young then eat their way out. A study in Science magazine confirms the genetics of wasp toxins rely heavily of the DNA of viruses that infected the insects millions of years ago.

BBC NEWS
 

Offline Chemistry4me

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:o That's neat, if not a bit freaky!
 

Offline neilep

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Orion Nebula: The Hubble View
Credit: NASA, ESA, M. Robberto (STScI/ESA) et al.










 Few cosmic vistas excite the imagination like the Orion Nebula. Also known as M42, the nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1,500 light-years away. The Orion Nebula offers one of the best opportunities to study how stars are born partly because it is the nearest large star-forming region, but also because the nebula's energetic stars have blown away obscuring gas and dust clouds that would otherwise block our view - providing an intimate look at a range of ongoing stages of starbirth and evolution. This detailed image of the Orion Nebula is the sharpest ever, constructed using data from the Hubble Space Telescope's Advanced Camera for Surveys and the European Southern Observatory's La Silla 2.2 meter telescope. The mosaic contains a billion pixels at full resolution and reveals about 3,000 stars.
 

Offline neilep

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The Helix Nebula from La Silla Observatory
Credit: WFI, MPG/ESO 2.2-m Telescope, La Silla Obs., ESO




 Will our Sun look like this one day? The Helix Nebula is one of brightest and closest examples of a planetary nebula, a gas cloud created at the end of the life of a Sun-like star. The outer gasses of the star expelled into space appear from our vantage point as if we are looking down a helix. The remnant central stellar core, destined to become a white dwarf star, glows in light so energetic it causes the previously expelled gas to fluoresce. The Helix Nebula, given a technical designation of NGC 7293, lies about 700 light-years away towards the constellation of Aquarius and spans about 2.5 light-years. The above picture was taken by the Wide Field Imager on the 2.2-meter Telescope at the European Southern Observatory's La Silla Observatory. A close-up of the inner edge of the Helix Nebula shows complex gas knots of unknown origin.
 

Offline Lincon

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Hi,
     Naked science makes an interesting facts about the new technologies. It has given a lot of contributions in the emerging new society.


Joe
 

Offline neilep

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Horsehead and Orion Nebulae



Credit & Copyright: Dale J. Martin (Massapoag Pond Obs.)


 Adrift 1,500 light-years away in one of the night sky's most recognizable constellations, the glowing Orion Nebula and the dark Horsehead Nebula are contrasting cosmic vistas. They appear in opposite corners of this stunning mosaic taken with a digital camera attached to a small telescope. The magnificent emission region, the Orion Nebula (aka M42), lies at the upper right of the picture. Immediately to its left is a prominent bluish reflection nebula sometimes called the Running Man. The Horsehead nebula appears as a dark cloud, a small silhouette notched against the long red glow at the lower left. Alnitak is the easternmost star in Orion's belt and is seen as the brightest star to the left of the Horsehead. Below Alnitak is the Flame Nebula, with clouds of bright emission and dramatic dark dust lanes. Pervasive tendrils of glowing hydrogen gas are easily traced throughout the region in this deep field image of the same region.

 

Offline neilep

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DRACULA FISH





--While he may not vant to suck your blood, the male fish seen above does sport spooky-looking fangs that have earned it the name Danionella dracula.

Researchers at London's Natural History Museum found several of the new species (bottom) in a tank of aquarium fish. Initially museum staff had thought the 0.7-inch-long (1.7-centimeter-long) creatures, caught in Myanmar (Burma), were part of an already known, related species.

"After a year or so in captivity, they started dying," museum scientist Ralf Britz told BBC News.

"When I preserved them and looked at them under the microscope, I thought, my God, what is this, they can't be teeth."

In fact, the fangs are not true teeth—the line of fish that gave rise to D. dracula is thought to have lost teeth around 50 million years ago.

By staining the bone and dissolving away tissue to reveal the full jawbones of dead specimens (top), Briz found that the odd species has rows of bony jaw protrusions (inset) that lack the pulp cavities and enamel caps of true teeth.

Despite their ghoulish appearance, the fangs likely aren't used for feeding.

"We did not study stomach contents, but we know that its close relatives live on small crustaceans … and other small invertebrates," Britz said in an email to National Geographic News. "In captivity it readily accepts brine shrimp [larvae], tiny nematodes, and even very fine flake food."

Based on the behavior of live "Dracula" fish, the researchers think the males use their extralong fangs to spar with each other during aggressive displays. The findings are described this week in the online edition of the Proceedings of the Royal Society B.

—Victoria Jaggard

Photographs courtesy Ralf Britz, Natural History Museum
 

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A Prominent Solar Prominence from SOHO
Credit: SOHO - EIT Consortium, ESA, NASA









 What's happened to our Sun? It was sporting a spectacular -- but not very unusual -- solar prominence. A solar prominence is a cloud of solar gas held above the Sun's surface by the Sun's magnetic field. In 2004, NASA's Sun-orbiting SOHO spacecraft imaged an impressively large prominence hovering over the surface, pictured above. The Earth would easily fit under the hovering curtain of hot gas. A quiescent prominence typically lasts about a month, and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System. Although somehow related to the Sun's changing magnetic field, the energy mechanism that creates and sustains a Solar prominence is still a topic of research.
 

Offline latebind

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ALL THESE PHOTOS ARE AMAZING!
 

Offline neilep

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ALL THESE PHOTOS ARE AMAZING!

aww thanks !

This thread is of course open to everybody to contribute to, but I am very grateful that you enjoy them latebind.
 

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Tycho's Supernova Remnant
Credit: X-ray: NASA/CXC/SAO; Infrared: NASA/JPL-Caltech; Optical: MPIA, Calar Alto, O. Krause et al.







 What star created this huge puffball? Pictured above is the best multi-wavelength image yet of Tycho's supernova remnant, the result of a stellar explosion first recorded over 400 years ago by the famous astronomer Tycho Brahe. The above image is a composite of an X-ray image taken by the orbiting Chandra X-ray Observatory, an infrared image taken by the orbiting Spitzer Space Telescope, and an optical image taken by the 3.5-meter Calar Alto telescope located in southern Spain. The expanding gas cloud is extremely hot, while slightly different expansion speeds have given the cloud a puffy appearance. Although the star that created SN 1572, is likely completely gone, a star dubbed Tycho G, too dim to be easily discerned here, is being studied as the possible companion. Finding progenitor remnants of Tycho's supernova is particularly important because the supernova was recently determined to be of Type Ia. The peak brightness of Type Ia supernovas is thought to be well understood, making them quite valuable in calibrating how our universe dims distant objects.
 

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The Seahorse of the Large Magellanic Cloud
Credit: NASA, ESA, and M. Livio (STScI)





To some it may look to some like a big space monster, but it is more big than monster. To others it may look like a grazing seahorse, but the dark object toward the image right is actually an inanimate pillar of smoky dust about 20 light years long. The curiously-shaped dust structure occurs in our neighboring Large Magellanic Cloud, in a star forming region very near the expansive Tarantula Nebula. The energetic nebula is creating a star cluster named NGC 2074, whose center is visible just off the top of the image in the direction of the neck of the seahorse. The above representative color image was taken last year by the Hubble Space Telescope's Wide Field Planetary Camera 2 in honor of Hubble's 100,000th trip around the Earth. As young stars in the cluster form, their light and winds will slowly erode the dust pillars away over the next million years.
 

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Signals of a Strange Universe
Credit: High-Z Supernova Search Team, HST, NASA





 Eleven years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernovae observations. Suggestions of a cosmological constant (lambda) were not new -- they have existed since the advent of modern relativistic cosmology. Such claims were not usually popular with astronomers, though, because lambda is so unlike known universe components, because lambda's value appeared limited by other observations, and because less- strange cosmologies without lambda had previously done well in explaining the data. What is noteworthy here is the seemingly direct and reliable method of the observations and the good reputations of the scientists conducting the investigations. Over the past eleven years, independent teams of astronomers have continued to accumulate data that appears to confirm the existence of dark energy and the unsettling result of a presently accelerating universe. The above picture of a supernova that occurred in 1994 on the outskirts of a spiral galaxy was taken by one of these collaborations.
 

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In the Heart of the Tarantula Nebula
Credit: ESA, NASA, ESO, & Danny LaCrue



BIG PICCY HERE (Makes a great desktop piccy)




In the heart of monstrous Tarantula Nebula lies huge bubbles of energetic gas, long filaments of dark dust, and unusually massive stars. In the center of this heart, is a knot of stars so dense that it was once thought to be a single star. This star cluster, labeled as R136 or NGC 2070, is visible just above the center of the above image and home to a great number of hot young stars. The energetic light from these stars continually ionizes nebula gas, while their energetic particle wind blows bubbles and defines intricate filaments. The above representative-color picture of this great LMC nebula details its tumultuous center. The Tarantula Nebula, also known as the 30 Doradus nebula, is one of the largest star-formation regions known, and has been creating unusually strong episodes of star formation every few million years.
 

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Scientists offer new theory for largest known mass extinction





Hypothetically speaking, large areas of the hyper saline Zechstein Sea and its direct environment
could have looked like this, which in the Permian Age was situated about where present day Central
 Europe is. At the end of the Permian Age the Zechstein Sea was irrevocably disconnected from the
open sea and the remaining sections of sea soon dried out after that. As a result the microbial-limited
halogenated gases from the Zechstein Sea stopped and vegetation was able to regenerate again. The pink
colour of the Zechstein Sea was probably brought about by microbes with an extreme preference for salt,
 as is the case with salt lakes today. In the background sand dunes can be recognised from a landscape
 with hardly any water. Photo: Dr. Karsten Kotte/Universität Heidelberg



MORE HERE
 

Offline neilep

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 Uh oh !..time to put the thinking caps on again !!

 
Hubble uncovers unusual supernova progenitor star
SPACE TELESCOPE SCIENCE INSTITUTE NEWS RELEASE


NASA's Hubble Space Telescope has identified a star that was one million times brighter than the Sun before it exploded as a supernova in 2005. According to current theories of stellar evolution, the star should not have self-destructed so early in its life.

"This might mean that we are fundamentally wrong about the evolution of massive stars, and that theories need revising," says Avishay Gal-Yam of the Weizmann Institute of Science, Rehovot, Israel.







 
 
The doomed star, which is estimated to have had about 100 times our Sun's mass, was not mature enough, according to theory, to have evolved a massive iron core of nuclear fusion ash. This is the prerequisite for a core implosion that triggers a supernova blast.

The finding appears today in the online version of Nature Magazine.

The explosion, called supernova SN 2005gl, was seen in the barred-spiral galaxy NGC 266 on October 5, 2005. Pre-explosion pictures from the Hubble archive, taken in 1997, reveal the progenitor as a very luminous point source with an absolute visual magnitude of -10.3.

The progenitor was so bright that it probably belonged to a class of stars called Luminous Blue Variables (LBVs), "because no other type of star is as intrinsically brilliant," says Gal-Yam. As an LBV-class star evolves it sheds much of its mass through a violent stellar wind. Only at that point does it develop a large iron core and ultimately explodes as a core-collapse supernova.

Extremely massive and luminous stars topping 100 solar masses, such as Eta Carinae in our own Milky Way Galaxy, are expected to lose their entire hydrogen envelopes prior to their ultimate explosions as supernovae. "These observations demonstrate that many details in the evolution and fate of LBVs remain a mystery. We should continue to keep an eye on Eta Carinae -- it may surprise us yet again," says supernova expert Mario Livio of the Space Telescope Science Institute, Baltimore, Md.

"The progenitor identification shows that, at least in some cases, massive stars explode before losing most of their hydrogen envelope, suggesting that the evolution of the core and the evolution of the envelope are less coupled than previously thought, a finding which may require a revision of stellar evolution theory," says co-author Douglas Leonard from San Diego State University, Calif.

One possibility is that the progenitor to SN 2005gl was really a pair of stars, a binary system that merged. This would have stoked nuclear reactions to brighten the star enormously, making it look more luminous and less evolved than it really is. "This also leaves open the question that there may be other mechanisms for triggering supernova explosions," says Gal-Yam. "We may be missing something very basic in understanding how a superluminous star goes through mass loss."

Gal-Yam reports that the observation revealed that only a small part of the star's mass was flung off in the explosion. Most of the material, says Gal-Yam, was drawn into the collapsing core that has probably become a black hole estimated to be at least 10 to 15 solar masses.

Gal-Yam and Leonard located the progenitor in archival images of NGC 266 taken in 1997. It was easily identifiable only because it is so superluminous. Only Hubble could clearly resolve it at such a great distance.

The team then used the Keck telescope to precisely locate the supernova on the outer arm of the galaxy. A follow-up observation with Hubble in 2007 unequivocally showed that the superluminous star was gone. To make sure the new observation was consistent with the 1997 archival image, the astronomers used the same Hubble camera used in 1997, the Wide Field Planetary Camera 2.

Finding archival images of stars before the stars exploded as supernovae isn't an easy task. Several other supernova progenitor candidates have been reported prior to the Hubble observation. The only other absolutely indisputable progenitor, however, was the blue supergiant progenitor to SN 1987A. In the case of SN 1987A, it was thought that the progenitor star was once a red supergiant and at a later stage evolved back to blue supergiant status. This led to a major reworking of supernova theory. The progenitor star observed by Gal-Yam is too massive to have gone through such an oscillation to the red giant stage, so yet another new explanation is required, he says.

 
 

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