Suddenly last Xmas.

[neufer]

What caused explosion that lit up Christmas sky?
Scientists look at either comet smacking into dense star or peculiar supernova death
By Charles Q. Choi

[b][color=#0000FF]An artist's impression of the model suggested for GRB 101225A. A. Simonnet, NASA, E/PO, Sonoma State University.[/color][/b]

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<<The Christmas sky last year was lit up by an extraordinarily powerful and mysteriously long-lasting explosion in space that scientists now suggest was a comet smacking into a dense star or a peculiar supernova death.

Radiation from gamma-ray bursts, the most powerful explosions ever seen in the universe, strikes Earth's atmosphere from random directions in space about twice a day. These bursts can be roughly divided into two kinds, ones lasting less than two seconds, and ones lasting up to minutes.

However, the strange gamma-ray burst detected on Christmas Day 2010 by NASA's Swift satellite lasted at least half an hour.

Scientists think shorter gamma-ray bursts are generally caused by merging neutron stars — dead stars made up of super-dense neutron matter. Longer bursts are typically thought to originate from hypernovas, in which giant stars that explode as incredibly powerful supernovas spew two opposing jets of energy as they die; we see them head-on as bursts.

However, researchers suspect a number of mysterious events of completely different origins could mimic gamma-ray bursts. Such might be the case with the Christmas burst, formally known as GRB 101225A.

"It is important to understand gamma-ray bursts to get some global picture of the life and death of massive stars," said astronomer Christina Thöne of the Institute of Astrophysics in Andalusia, Spain. "Massive stars are ultimately the ones that decide what elements are present, created and recycled in the gas in our and any other galaxy."

Now scientists have two competing explanations for the Christmas burst: a cosmic impact on a dead star in our galaxy, or a peculiar supernova in a

Based on the length and brightness of the burst, astrophysicist Sergio Campana at the Astronomical Observatory of Brera in Italy and his colleagues suggest that a minor body such as a comet or asteroid crashed into a neutron star.

"I think this is the discovery of a completely new astrophysical phenomenon that has not been envisaged before," Campana told Space.com.

Specifically, the astrophysicists suggest that the gravity of a neutron star ripped apart a 500 trillion-metric-ton chunk of matter that had been passing within 3,000 miles (5,000 kilometers) of it. The debris fell onto the star and exploded as energy.

"If tidal disruption of minor bodies around neutron stars is really happening, I would expect GRB 101225A not (to) be unique," Campana said. "I would like to start searching for this kind of event either in existing data sets or with new observations."

On the other hand, Thöne and her colleagues say an oddball supernova might be to blame. They propose that the Christmas explosion occurred when a neutron star combined with a helium star, a type of super-giant star rich in helium. When the neutron star and the helium star's core merged, the result would have been a black hole or a highly magnetic neutron star known as a magnetar, either of which might power long bursts of radiation. The helium star would have shed its outer layers first, surrounding the duo in an envelope of gas — which could explain unusual details seen in the burst's light.

To test which explanation might be correct, scientists must figure out if the explosion took place in our galaxy or not. Thöne and her colleagues observed signs that it took place in a distant galaxy, but the evidence is ambiguous, they noted. Further observations with the Hubble Space Telescope and other observatories could help solve the mystery.

"We hope to settle the question on the right model sometime in the future," Thöne said. "Hopefully sometime next year we will know more."

The scientists detailed their findings in two papers published in the Dec. 1 issue of the journal Nature.>>

[BMAONE23]

Click to play embedded YouTube video.

[Beyond]

Lit up the sky last Xmas for half an hour huh Well... just one more thing to add to my 'missed' list. Did anybody here actually get to see it?? If so, what did it look like?

[neufer]

Lit up the sky last Xmas for half an hour huh Well... just one more thing to add to my 'missed' list.
Did anybody here actually get to see it?? If so, what did it look like?

I'm only sensitive to Thanksgiving Obamma-ray bursts.

[Chris Peterson]

Lit up the sky last Xmas for half an hour huh :?: Well... just one more thing to add to my 'missed' list. Did anybody here actually get to see it?? If so, what did it look like?

It "lit up the sky" if you have meter-sized eyes and gamma ray sensitive retinas. Otherwise, it looked like nothing at all.

[Beyond]

Ah, thanks Chris. Now where did i put that eraser.

[neufer]

Lit up the sky last Xmas for half an hour huh Well... just one more thing to add to my 'missed' list. Did anybody here actually get to see it?? If so, what did it look like?

It "lit up the sky" if you have meter-sized eyes and gamma ray sensitive retinas. Otherwise, it looked like nothing at all.

I don't think that we've ever seen a picture of Beyeond.

[Sam]

I don't think that we've ever seen a picture of Beyeond.

Sure we have

Click to play embedded YouTube video.

[owlice]

Beyond the blue...

[Beyond]

Hey!! I'm Beyond everything. But with only 1-e, or it ain't me you see.

[Beyond]

"No avian society ever develops space travel because it's impossible to focus on calculus when you could be outside flying." -Randall Munroe

Calculus.... Wasn't that a famous Roman

[rstevenson]

Yes, full name Calculus Limitus Derivatus, the Roman god of insanity.

Rob
(Don't mind me; I just wrote an exam this morning.)

[bystander]

Swift Finds Gamma-Ray Burst with Dual Personality
NASA GSFC Swift | 2011 Nov 30

Click to play embedded YouTube video.

A peculiar cosmic explosion first detected by NASA's Swift observatory on Christmas Day 2010 was caused either by a novel type of supernova located billions of light-years away or an unusual collision much closer to home, within our own galaxy. Papers describing both interpretations appear in the Dec. 1 issue of the journal Nature.

Gamma-ray bursts (GRBs) are the universe's most luminous explosions, emitting more energy in a few seconds than our sun will during its entire energy-producing lifetime. What astronomers are calling the "Christmas burst" is so unusual that it can be modeled in such radically different ways.

"What the Christmas burst seems to be telling us is that the family of gamma-ray bursts is more diverse than we fully appreciate,” said Christina Thoene, the supernova study's lead author, at the Institute of Astrophysics of Andalusia in Granada, Spain. It's only by rapidly detecting hundreds of them, as Swift is doing, that we can catch some of the more eccentric siblings."

Common to both scenarios is the presence of a neutron star, the crushed core that forms when a star many times the sun's mass explodes. When the star's fuel is exhausted, it collapses under its own weight, compressing its core so much that about a half-million times Earth's mass is squeezed into a sphere no larger than a city.

The Christmas burst, also known as GRB 101225A, was discovered in the constellation Andromeda by Swift's Burst Alert Telescope at 1:38 p.m. EST on Dec. 25, 2010. The gamma-ray emission lasted at least 28 minutes, which is unusually long. Follow-up observations of the burst's afterglow by the Hubble Space Telescope and ground-based observatories were unable to determine the object's distance.

Thoene's team proposes that the burst occurred in an exotic binary system where a neutron star orbited a normal star that had just entered its red giant phase, enormously expanding its outer atmosphere. This expansion engulfed the neutron star, resulting in both the ejection of the giant's atmosphere and rapid tightening of the neutron star's orbit.

Once the two stars became wrapped in a common envelope of gas, the neutron star may have merged with the giant's core after just five orbits, or about 18 months. The end result of the merger was the birth of a black hole and the production of oppositely directed jets of particles moving at nearly the speed of light, followed by a weak supernova.

The particle jets produced gamma rays. Jet interactions with gas ejected before the merger explain many of the burst's signature oddities. Based on this interpretation, the event took place about 5.5 billion light-years away, and the team has detected what may be a faint galaxy at the right location.

"Deep exposures using Hubble may settle the nature of this object," said Sergio Campana, who led the collision study at Brera Observatory in Merate, Italy.

If it is indeed a galaxy, that would be evidence for the binary model. On the other hand, if NASA's Chandra X-ray Observatory finds an X-ray point source or if radio telescopes detect a pulsar, that goes against it.

Campana's team supports an alternative model that involves the tidal disruption of a large comet-like object and the ensuing crash of debris onto a neutron star located only about 10,000 light-years away. The scenario requires the break-up of an object with about half the mass of the dwarf planet Ceres. While rare in the asteroid belt, such objects are thought to be common in the icy Kuiper belt beyond Neptune. Similar objects located far away from the neutron star may have survived the supernova that formed it.

Gamma-ray emission occurred when debris fell onto the neutron star. Clumps of cometary material likely made a few orbits, with different clumps following different paths before settling into a disk around the neutron star. X-ray variations detected by Swift's X-Ray Telescope that lasted several hours may have resulted from late-arriving clumps that struck the neutron star as the disk formed.

In the early years of studying GRBs, astronomers had very few events to study in detail and dozens of theories to explain them. In the Swift era, astronomers have settled into two basic scenarios, either the collapse of a massive star or the merger of a compact binary system.

"The beauty of the Christmas burst is that we must invoke two exotic scenarios to explain it, but such rare oddballs will help us advance the field,” said Chryssa Kouveliotou, a co-author of the supernova study at NASA's Marshall Space Flight Center in Huntsville, Ala.

The unusual gamma-ray burst GRB 101225A explained as a minor body falling onto a neutron star - S. Campana et al

• Nature 480 69 (01 Dec 2011) DOI: 10.1038/nature10592
  A Christmas comet falling onto a neutron star

The unusual gamma-ray burst GRB 101225A from a helium star/neutron star merger at redshift 0.33 - C. C. Thöne et al

• Nature 480 72 (01 Dec 2011) DOI: 10.1038/nature10611
  An unusual stellar death on Christmas Day

[neufer]

"No avian society ever develops space travel because it's impossible to focus on calculus when you could be outside flying."
-Randall Munroe

Calculus.... Wasn't that a famous Roman

Yes, full name Calculus Limitus Derivatus, the Roman god of insanity.

__ Auguste Piccard in 1932

<<Professor Cuthbert Calculus (Professeur Tryphon Tournesol, literally Professor Tryphonius Sunflower: Tryphon was the name of Hergé's plumber) is a fictional character in The Adventures of Tintin, the series of classic Belgian comic books written and illustrated by Hergé. He is a distracted, hard-of-hearing scientist who invents many sophisticated devices used in the series, such as a one-person shark-shaped submarine, the Moon rocket and an ultrasound weapon. Calculus first appeared in Red Rackham's Treasure, and was the end result of Hergé's long quest to find the archetypal mad scientist or absent-minded professor. Although Hergé had included characters with similar traits in earlier stories, Calculus developed into a much more complex figure as the series progressed.

Calculus is partly modeled on inventor Auguste Piccard (1884–1962), Hergé stated in an interview with Numa Sadoul: "Calculus is a reduced scale Piccard, as the real chap was very tall. He had an interminable neck that sprouted from a collar that was much too large... I made Calculus a mini-Piccard, otherwise I would have had to enlarge the frames of the cartoon strip." The Swiss physics professor held a teaching appointment in Brussels when Hergé spotted his unmistakable figure in the street. In The Castafiore Emerald, Bianca Castafiore mentions that Calculus is "famous for his balloon ascensions", an ironic reference to Piccard.

Calculus is a genius, who demonstrates himself throughout the series to be an expert in many fields of science, holding three PhDs in nuclear and theoretical physics, planetary astronomy and calculus. He is also an experienced engineer, archaeologist, biologist and chemist. Many of his inventions precede or mirror similar technological developments in the real world (most notably the Moon rocket, but also his failed attempt at creating a colour television set). He seeks to benefit mankind through his inventions, developing a pill that cures alcoholism by making alcohol unpalatable to the patient, and refusing under great duress to yield his talents to producing weapons of mass destruction. Much of Calculus's more dangerous work is criticized by Captain Haddock, although Calculus usually interprets this the other way round: his deafness often leads him to misinterpret Haddock's words, preventing him from hearing his real opinion.

Calculus's deafness is a frequent source of humour in his interactions with other people, as he often repeats back what he thinks he has heard, usually in the most unlikely words possible. Additionally, he often diverts the subject of a conversation by responding to a misinterpreted remark. For example, "But I never knew you had..." leads Calculus to respond "No, young man, I am not mad!". In the same book he believes that Tintin and Haddock are talking about his sister, before remembering a few moments later that he does not have a sister. He is not perturbed by his handicap, even if it is a source of deep frustration to his friends. He himself does not admit to being near-deaf and insists that he is "only a little hard of hearing in one ear."

In the course of the Moon books, however, Calculus leads a team of scientists and engineers working on a major rocket project, motivating him to adopt an ear trumpet, and later a hearing aid, and for the duration of the adventure he has near-perfect hearing. This made him a more serious character, even displaying leadership qualities which had not been shown before or since. However, after completing the journey to the Moon, Calculus discarded his hearing aid, forcing his friends to readjust to his hearing impairment; this restored the humour surrounding him, though it could be that he finds his deafness useful since it enables him to focus on his work.

Calculus maintains a laboratory at Marlinspike Hall, in which he conducts various experiments. He is fairly protective of his work, on occasion hiding his scientific endeavours from Tintin and Haddock (which gets him into trouble in The Calculus Affair). His lab is also stripped of all its apparatus in the same book. On an earlier occasion, during his efforts to find an antidote to Formula Fourteen in Land of Black Gold, Calculus almost destroyed half of Marlinspike in an explosion.

Although generally a mild-mannered (if somewhat oblivious) figure, Calculus flies into an uncharacteristic rage if he feels insulted or ridiculed. He is especially provoked if he ever hears the Captain (or anyone else) call him a "goat". On one famous occasion in Destination Moon, he displays uncontrollable ire ("Goat, am I?") when an irritated Haddock accuses him of "acting the goat" by attempting to build a Moon rocket. His subsequent tirade and blatant disregard for security terrifies the usually ebullient Captain; he even lifts the director of security barring his way onto a coat-hanger. Another occasion is in Flight 714 when, due to some misunderstanding, he physically assaults Laszlo Carreidas and has to be held back with great effort by Haddock and Tintin. In the same book, despite his deafness, he hears Captain Haddock tell him that he's "acting the goat", but Haddock quickly prevents the severe reaction from occurring quickly.

In spite of all this, his friends stick by him come what may. Haddock invited him to stay at Marlinspike Hall after Calculus discovered it is the captain's ancestral home and bought it in his name thanks to money he had earned through selling the patent for his shark-submarine. He did this because Haddock and Tintin had provided him with the opportunity to test the submersible when they were searching for Red Rackham's treasure. Tintin and Haddock crossed the world on at least two occasions (Prisoners of the Sun and The Calculus Affair) in order to save him from kidnappers.

He occasionally comments that he was a great sportsman in his youth, with a very athletic lifestyle. He is a former practitioner of the French martial art savate, although a demonstration in Flight 714 shows him to be a bit rusty.

In contrast to his unquestionable scientific merits, Calculus is a fervent believer in dowsing, and carries a pendulum for that purpose. Hergé himself was a believer in the subject: dowser Victor Mertens had used a pendulum to find the lost wedding ring of Hergé's wife in October 1939.

Before Calculus appeared in Red Rackham's Treasure, Hergé had featured other highly-educated but eccentric scholars and scientists, such as:

• Dr. Sarcophagus of Cigars of the Pharaoh who showed signs of being clumsy and forgetful before going completely mad.
  
  The absent-minded professor who appeared in The Broken Ear and who forgot his glasses, wore his cleaning-lady's overcoat, held his cane upside-down as if it were an umbrella, mistook a parrot for a man and left his briefcase next to a lamp post. (In the original edition published in 1935 his name is given as Professor Euclide, after the Greek mathematician known as the "Father of Geometry".)
  
  Professor Hector Alembick in King Ottokar's Sceptre, who had a bad habit of throwing his cigarettes on the floor.
  
  Two astronomers from The Shooting Star also showed unusual and, in one case, mad behaviour: Philippulus the Prophet represented the dilemmas some face over religious belief and scientific research. In his case the conflict took a toll on his mind when the end-of-the-world appeared to be imminent. He then went around wearing bedsheets and beating a gong to warn of the event and later disrupted the eve of departure of the expedition sent to find a meteorite. His colleague, Professor Decimus Phostle, though not mad, looked forward to the end of the world whose prediction he thought would make him famous. In contrast, he showed signs of maturity during the expedition when he called off the search for the meteorite in order to help a ship in distress.

While he sometimes appears aloof when absorbed in his work, Calculus corresponds with other scientists and also collaborates with many of them on his projects. Notably, he works with Baxter and Frank Wolff on the Moon rocket and corresponds with ultrasonics expert Alfredo Topolino of Nyon in The Calculus Affair.

Calculus is the only regular character in the Tintin series to display signs of attraction to women. This is notably evident in his interactions with Bianca Castafiore, with whom he is smitten during her long stay at Marlinspike Hall in The Castafiore Emerald. During her stay, his botanic experiments lead him to create a new variety of rose, which he names in her honour. Calculus is also distressed by Castafiore's imprisonment in Tintin and the Picaros, and is adamant on going to her defence. In the same book, he is charmed by the unattractive Peggy Alcazar (wife of General Alcazar).>>

[Beyond]

...inventor Auguste Piccard (1884–1962)...

Ah, must have been Jean-luc Piccard's father Now we know what craziness inspired Jean-luc to become captain of a starship and go trapesing around the universe.

[neufer]

...inventor Auguste Piccard (1884–1962)...

Ah, must have been Jean-luc Piccard's father

Now we know what craziness inspired Jean-luc to become captain of a starship and go traipsing around the universe.

<<Jean Felix Piccard (Basel, Switzerland, January 28, 1884 – January 28, 1963, Minneapolis, Minnesota), also known as Jean Piccard, was a Swiss-born American chemist, engineer, professor and high-altitude balloonist. He invented clustered high-altitude balloons, and with his wife Jeannette, the plastic balloon. Piccard's inventions and co-inventions are used in balloon flight, aircraft and spacecraft. Captain Jean-Luc Picard of Star Trek is named for one or both of him and his twin brother Auguste - in fact, it was sometimes hinted that the character may be descended from the scientist.>>