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Astronomers from the European Southern Observatory settled today a year long dispute whether a big red orb five times the mass of Jupiter and orbiting a young brown dwarf star is indeed a planet. "I'm more than 99 percent confident" that the object is a planet, said Benjamin Zuckerman, UCLA professor of physics and astronomy and member of NASA's Astrobiology Institute. "The two objects are moving together; we have observed them for a year, and the new images essentially confirm our 2004 finding."
This is the first time astronomers have photographed a planet outside out solar system. Although more than 150 such extra-solar planets have been found, they were detected by measuring the wobble or the changes in luminosity of their anchor stars.
The scientists also sketched out a rough chemical make-up of the planet. They said that the spectrum of the radiation leaving the planet "presents a strong signature of water molecules, thereby confirming that it must be cold." Said Anne-Marie Lagrange of the Grenoble Observatory in France: "Our discovery represents a first step towards one of the most important goals of modern astrophysics: to characterize the physical structure and chemical composition of giant and, eventually, terrestrial-like planets.
ESO astronomer Gael Chauvin said that the giant planet "most probably did not form like the planets in our solar system. Instead it must have formed the same way our Sun formed, by a one-step gravitational collapse of a cloud of gas and dust."
The distance between the planet, labeled 2M1207b, and the brown dwarf, numbered 2M1207A, is 55 times larger than the radius of Earth's orbit around the Sun. The planet is near the southern constellation of Hydra and approximately 200 light years from Earth. It was first photographed last April.

Harvard astronomers using NASA's Chandra X-ray Observatory have snapped a stunning picture of a tiny dwarf star cannibalizing its giant neighbor.
The stars, called Mira A and B, are about 6.5 million miles apart (circa 1.5 light years), as far as the Sun and Pluto. They are 420 lights years away from us in the constellation Cetus (Whale).
The stars are connected by a bridge of burning matter. The small and dense Mira B is pulling off and gorging on gas from the huge and bloated Mira A, and burping bursts of X-rays as it feasts.
Or so people thought. The new images also reveal unexpected X-ray radiation from Mira A. The astronomers said that the "internal turmoil" in the bloated Mira A could "create magnetic disturbances in the upper atmosphere of the star and lead to the observed X-ray outbursts, as well as the rapid loss of material from the star in a blustery, strong, stellar wind. Some of the material in the wind from Mira A is captured in an accretion disk around Mira B, where collisions between rapidly moving particles produce X-rays."
Said Margarita Karovska of the Harvard-Smithsonian Center for Astrophysics:
"Before this observation it was assumed that all the X-rays came from a hot disk surrounding a white dwarf, so the detection of an X-ray outburst from the giant star came as a surprise."
Mira A, whose diameter is 600 times larger than the Sun, is a red giant, an aging star whose nuclear fuel of hydrogen and helium will soon burn out. Renaissance astronomers named the star Mira, which means "Wonderful" in Latin, since it would dim and brighten every 331 days. The blinking is caused by the much smaller Mira B passing in front of it. Mira B is thought to be a white dwarf star about the size of the Earth.

Astronomers at the European Space Agency have spotted features as small as a football field on stars as far as 2,000 light years, something that's never been done.
Using the XMM-Newton X-ray telescope, the scientists have observed thousands of burnings flecks spread over stellar surfaces and ranging from 300 to 3,000 feet in diameter on three neutron stars 500, 800, and 2000 light years away from us.
ESA said that the stellar pimples are most probably linked to magnetic field phenomena similar to earthly Polar lights. "This is where the star's magnetic field funnels charged particles back towards the surface, in a way somehow similar to the Northern light, or aurorae, seen at the poles of planets which have magnetic fields, such as Earth, Jupiter and Saturn," the scientists said.
Neutron stars are the fast-spinning, superdense cores that remain after supernova explosions. They are made almost entirely of neutrons and about as massive as the Sun. But their circumference is thousands times smaller, just 30 to 600 miles. Say, a Lego cube made of neutron star material with sides 1 centimeter long (2/5ths of an inch)would weigh as much as 340-meter cube of steel. Working like massive dynamos, they generate extreme magnetic fields.

Researchers at Washington University is St. Louis have developed blood-borne nanoparticles that can be loaded with a wide variety of drugs and directed to growing tumors.
The particles, each made of 100,000 molecules of undisclosed metal, carry an imaging agent that can be picked up by a MRI scanner and let doctors determine whether the drug reached its target. "When drug-bearing nanoparticles also contain an imaging agent, you can get a visible signal that allows you to measure how much medication got to the tumor," Gregory Lanza, associate professor of medicine. "You would know the same day you treated the patient and if the drug was at a therapeutic level." Since such imaging technology would disclose whether a drug therapy is working, it could dramatically lower doses typically used in chemotherapy, making the procedure potentially much safer.
The particles enter milimeter-sized, rapidly growing tumors by penetrating tiny new blood vessels, which feed them. To get the particles to bind to tumors, the researchers equipped them with tiny "hooks" that link only to complementary "loops" found on cells in newly forming blood vessels. When the nanoparticles hooked the "loops" on the new vessels' cells, they revealed the location of the tumors.
(For more on nano-MRI see Pumping Iron, March 20, and In Dust They Trust, March 17.)

Astronomers at the European Southern Observatory have snapped new images of the Blob, a sinister-looking reddish cloud of ionized gas in the Milky Way's cosmic sidekick, the Large Magellanic Cloud. The Blob looks like a cracked reptilian egg stretching some four light-years across. It's lit from withing by a powerfull object 200,000 times more luminous that the Sun. The astronomers speculate that the light source might be a very massive star of some 100 stellar masses in the process of being born.
"It is possible that the blob resulted from massive star formation following the collapse of a thin shell of neutral matter," said ESO astronomer Mohammad Heydari-Malayeri. Added his colleague Frederic Meynadier: "The formation mechanisms of these objects are not yet fully understood." Meynadier said that so far only a dozen of such "blobs" have been discovered.

Scientists at the Lawrence Livermore National laboratory studying an ancient meteorite say they have determined the age of the solar system. By their counting, our cosmic neighborhood started condensing from a cloud of interstellar dust and gas between 4.567 billion and 4.565 billion years ago.
The scientists made the discovery by studying chondrules, milimeter-sized spheres thought to be among the first solids to have formed in the solar nebula, and "calcium aluminum inclusions" called CAIs.
Chondrules and CAIs have never been found in any terrestrial rocks, but they are often embedded in space rocks like the massive Allende meteorite, which crashed in Mexico in 1969 and scattered tons of debris over 100 square miles.
Both chondrules and CAIs contain strange isotopic signatures that pointed to their birth before the solar system formed. The assumption was that these tiny objects were probably the product of a nearby supernova.
The Livermore scientists working hand in had with researchers in Hawaii, Tokyo, the Smithsonian and MIT dated the oxygen 16 isotope present in Allende's chondrules and CAIs to crack the riddle. They discovered that the CAIs and chondrules were born about two million year apart, but tens of millions of years before any planets in the solar systems. Earth and the rest of the solar rocks are thought to have formed about 4.5 billion years ago.
"Over this span of about two million years, the oxygen in the solar nebula changed substantially in its isotopic makeup," said Livermore's Ian Hutcheon. "In the past the age difference between CAIs and chondrules was not well-defined. Refining the lifetime of the solar nebula is quite significant in terms of understanding how our solar system formed."

They're green, they're little, they may have lived on Mars, but men they ain't. Scientists from the University of Colorado at Boulder have found a strange bunch of green microbes living inside acid-infused simmering rocks at the Yellowstone National Park. The researchers said that the discovery could be a boon for astrobiologist searching for life on Mars.
"This is the first description of these microbial communities, which may be a good diagnostic indicator of past life on Mars because of their potential for fossil preservation," said team member Jeffrey Walker. "The prevalence of this type of microbial life in Yellowstone means that Martian rocks associated with former hydrothermal systems may be the best hope for finding evidence of past life there."
Walker's colleague Norman Pace said that "the pores in the rocks where these creatures live have a pH value of one, which dissolves nails. This is another example that life can be robust in an environment most humans view as inhospitable."

There's more news today coming out of Brookhaven about their big bang experiment. Danish physicists from the Niels Bohr Institute at the University of Copenhagen who took part in the research said that when the universe was just one microsecond old it behaved like a perfect liquid.
Until recently, researchers have thought that the quarks and gluons that appeared right after the big bang formed a gas. "The latest results from RHIC, however, indicate that under the extreme conditions just around the phase transition from quarks and gluons to ordinary matter, the quarks and gluons behaved as a liquid, in fact an almost perfect liquid," the reserachers said in a press release.
The scientist said that the liquid, burning at 1,000 billion degress Kelvin seemed to move "in a pattern that exhibits a high degree of coordination among the particles -- somewhat like a school of fish that responds as one entity while moving through a changing environment."

Researchers at the Relativistic Heavy Ion Collider in Brookhaven, NY have distilled a close cousin of quark-qluon plasma, the cosmic cocktail that existed just millionth of a second after the Big Bang.
The Brookhaven brew made by smashing gold nuclei accelerated close to the speed of light could tell us what the universe was like during the big bang, as well as provide experimental verifications of some of the arcane predictions made by string theory, which seeks to unify the laws of relativity and quantum physics. "We know that we've reached the temperature up to 150,000 times hotter than the center of the sun and energy density predicted to be necessary for forming such a plasma," said Sam Aronson, Brookhaven's Associate Laboratory Director for High Energy and Nuclear Physics.
Such temperatures should be hot enough to melt the very vacuum of space like ice and create unattached free quarks and gluons seemingly out of nothing, the researchers said.
Quarks and gluons are the basic building blocks of atomic nuclei. They make protons, neutrons and a host of other more exotic particles.

It may be a good time to pawn your "rocks." A diamond star discovered last year hovers in the southern skies (see Bling, Bling Star). Now American scientists are saying that some of the 154 extrasolar planets found over the last decade could be also made of diamond. They said that such planets could be located even around stars like our Sun.
Marc Kuchner of Princeton University and Sara Seager of the Carnegie Institution in Washington said in a brand new paper that there could be low-mass extrasolar planets - smaller than 60 times the Earth's mass - rich in silicon carbide and other carbon compounds. "Although graphite should emerge as a surface layer in a differentiated carbon planet, a few kilometers into the planet's interior... pure carbon in a cool carbon planet should turn to diamond."
Kuchner and Seager got the idea to look for carbon planets from recent research done on the birth of Jupiter. Data suggested that Jupiter formed in a carbon-rich part of the primordial solar nebula and that Jupiter's embryo was a carbon planet. "If Jupiter could have formed from a carbon-rich embryo, we would expect that carbon-rich embryos should be relatively common and occassionaly observable as planets," they wrote.

There are many spectacular sights in the universe, but a giant diamond suspended in the southern skies outshines them all. The cosmic gem known as BPM 37093 is actually a white dwarf. Such stars are the hot cores of stars like our sun left over after they use up their nuclear fuel and die. This particular white dwarf is made mostly of crystalized carbon, i.e. diamond, draped with a thin gasseous veil of hydrogen and helium.
The diamond star is located in the constellation Centaurus just short 50 light years away. It is 2,500 miles across and weighs 5 million trillion trillion pounds, which translates to approximately 10 billion trillion trillion carats.
"It's the mother of all diamonds!" said astronomer Travis Metcalfe from Harvard-Smithsonian Center for Astrophysics who led the team that made the discovery. "Some people refer to it as 'Lucy' in a tribute to the Beatles song 'Lucy In The Sky With Diamonds.'"
Team member Michael Montgomery from the Univresity of Cambridge said that "the hunt for the crystal core of this white dwarf has been like the search for the Lost Dutchman's Mine. It was thought to exist for decades, but only now has it been located."The team also said that the star rings like a "gigantic gong", undergoing constant pulsations.
Metcalfe said the team made the discovery by "measuring those pulsations, we were able to study the hidden interior of the white dwarf, just like seismograph measurements of earthquakes allow geologists to study the interior of the Earth. We figured out that the carbon interior of this white dwarf has solidified to form the galaxy's largest diamond."
The scientists wrote that our Sun will become a white dwarf when it dies 5 billion years from now. Some two billion years after that, the Sun's ember core will crystallize as well, leaving a giant diamond in the center of our solar system.
Although Lucy has been found a year ago, it's can be best viewed right now if you and your telescope happen to be in the southern hemisphere. The window on Lucy will close in June for another ten months.

Black holes have lost some of their enigma at the Physics 2005 conference held this week at the Institute of Physics in Warwick, England. First, Astrophysics professor Andrew Hamilton from the University of Colorado showed that space travelers getting close to the event horizon of a big black hole would be fried to death, rather than torn to pieces. Since gravity at an event horizon is proportional to the mass of a black hole divided by the horizon's area, the bigger the horizon the weaker its gravitational pull. In theory, it would be possible to travel near the surface of a gigantic black hole the size of billions of suns and fly safely back.
Not so, says Hamilton. He says that the core of any black hole is filled with hot, dense plasma slowly sinking into the infinitely dense and infinitely tiny singularity at its center. Anybody approaching the horizon would be incinerated by the plasma before he would have time to take off and write home.
Astronomer Royal Martin Reese and his group later reported that the huge black holes located in the centers of galaxies have been formed by mergers of small black holes rather than by gobbling up galactic material. In a twist, Reese's Cambridge colleague Martin Haehnelt said that a proof for this theory would be finding a galaxy with its central black hole missing. He explained that a black hole merger begins with two holes going into orbit around each other and spiralling ever closer together. In the cataclysmic blast of energy when they finally merge, any asymmetry can send the resulting black hole flying off into space. Said Martin Haehnelt: "If this happened we might find the occasional galaxy with its central supermassive black hole missing."

Aping America's color-coded terror warnings, astronomers at MIT have overhauled the Torino Scale used to measure the likelihood of Earth's doomsday collision with comets and asteroids. The new chart has a colored scale from zero to ten. It goes from harmless white to blazing chimney red for the "certain global catastrophe" warning.
Perhaps most interesting is Level 8, the first of the chart's three red alerts. It will be called when "a collision is certain, capable of causing localized destruction for an impact over land or possibly a tsunami if close offsore. Such events occur on average between once per 50 years and oncer per several 1000 years," the chart says.
Uh oh. The Tunguska meteorite, a likely Level 8 event, exploded above the Taiga in 1908, nearly a century ago. It felled an estimated 60 million trees over 2,150 square kilometres but did not leave a crater. The impact was felt as far away as 1,000 kilometres. At 500 kilometres, witnesses had claimed to have heard a deafening bang and to have seen a cloud on the horizon. The power of the blast was estimated between 10 and 15 megatons of TNT, about the size of the Hiroshima bomb.
The scientists aren't worried. They said that the highest Torino level ever given to an asteroid was a four (yellow) last December, with a 2 percent chance of hitting Earth in 2029. After extended tracking of the asteroid's orbit, it was reclassified to level zero.

Scientists at MIT have found a protein that stops neurons from committing apoptosis, or programmed cell suicide. They hope that braking brain cell death will help them rejuvenate damaged and diseased brain tissue in adults. The protein, called CPG 15, may also let them grow neurons outside the body and replace dead brain cells like broken screws.
The scientists said that neurons are commonly killed off during the early brain development when brain cell rapidly proliferate. But they pointed out that little is known how apoptosis works in the adult brain. Elly Nedivi, professor of brain and cognitive sciences at MIT, said that the protein can "drastically affect the final size and shape of the cortex." He said that extra CPG 15 gives rats bigger brains with "grooves and furrows like evolved mammalian brains with larger surface area." Now if only size equalled smarts.

Neurosurgeons at Ohio State University have designed a killer virus that can slay brain tumor cells. The virus is a genetically altered herpes simplex virus that infects and reproduces only in malignant glioma cells and kills them, leaving other cells and tissues unharmed.
Malignant gliomas are fatal, progressive cancers in the brain. The average survival following diagnosis is about a year, said E. Antonio Chiocca, professor and chairman of neurological surgery at The Ohio State University Medical Center. They are usually treated using surgery, chemotherapy and radiation.
Chiocca engineered the killer virus to attack only cells that make a protein called nestin. The protein is produced by malignant glioma.
The researchers tested the virus in mice with implanted human gliomas. In one set of experiments, the researchers gave the virus to the mice early, seven days after implanting the tumors. Untreated mice lived for 21 days after tumor implantation. Eight of 10 mice treated with the virus survived 90 days after implantation. Two of 10 mice treated with a control virus survived 90 days.
Using the virus as a viable cancer therapy is still years away, though. "This is a preliminary study," said Chiocca. "This virus cannot yet be used in humans. To go from animal studies to human studies is a very long process, especially for a treatment that uses viruses."
This is not the first time neurosurgeons used the herpes virus to treat cancer. In 1992, Kenneth Culver, an oncology researcher at the National Cancer Institute, injected a modified retrovirus carrying a gene from the herpes virus directly into the brain tumors of mice and later humans. Soon, the tumors started expressing the herpes gene. Matt Ridley writes in Genome that "by then the cunning Dr. Culver was treating the patient with drugs for herpes and the drugs attacked the tumors. It seemed to work on the first patient, but on four of the next five it failed."

Astrophysicists at the University of Manchester studying a distant nova have found clues on how such exploding stars helped to create the elements we and our planet are made of.
The scientists were using a giant radio telescope in the New Mexico desert to study the so-called Sakurai's Object located in the Sagittarius constellation. It is the only dying star that has been seen to blast back to life in modern times.
Albert Zijlstra, astrophysics professor at Manchester, said that the exploding star disgorged a large amount of carbon gas and dust into space. "These will find their way into regions of space where new stars form, and the dust grains may become incorporated in new planets." he said. "Our results suggest this source for cosmic carbon may be far more important than previously suspected." Zijlstra said that as much as 5% of the carbon on Earth may have come from similar stellar explosions.
Most of the other elements are created during much bigger, cataclysmic events called supernovas. The cores of such stars collapse to form so-called white dwarfs, neutron stars, or black holes.
The majority of stars cool down and die when they have used up most of their hydrogen fuel by converting it into helium. For the Sun, this will happen in about 4.5 billion years. [Before that, the sun will become a red giant, 100 times larger and 2,000 times more luminous, expanding near Mars's orbit and incinerating Earth as it grows.]
But some 25% of stars will experience a brief rebirth when their helium suddenly ignites and starts fusing into carbon. After the explosive re-ignition, the star will expand to giant proportions - expelling tonnes of carbon in the process - before rapidly burning out again. Zijlstra expects that the Sakurai's Object will cool down and die sometime after 2200.

Scientists at Yale University have learned to remotely control fruit flies with laser pulses by genetically rigging their brains. They even made headless flies fly!
The researchers said that the laser made the flies jump, beat their wings and fly in an escape response. They also used laser light to activate the flies' dopamine neurons that stimulated walking and affected the types of paths the flies chose to follow.
"The ability to control brain functions non-invasively opens many new possibilities for the analysis of neural circuits, the search for the cellular substrates of behavior, and, possibly even restoring function after injury or disease,"
said Gero Miesenbock, associate professor of cell biology at Yale. "This is a significant step toward moving neuroscience to active and predictive manipulation of behavior."
Mind control? Not really. The researchers showed "that even headless flies take mindful flight if the correct set of neurons is photo-activated." Sighs one New York City boss: "If only laser like that worked on people, I'd have an easier job managing!"

American scientists have found a chunk of human chromosome that may have caused the split of hominids from chimpanzees and launched the emergence of the human race five million years ago.
LaDeana Hillier of the Genome Sequencing Center at Washington University School of Medicine in St. Louis said she and her colleagues found on human chromosome 2 what "we think may be remnant of the centromere of one of the two chimp chromosomes that merged to form the human chromosome 2."
A centromere is the "cinched" part of the chromosome where the where the chromatids, the chromosome's two rods, are held together to form an X shape.
Human chromosome 2, the second largest human chromosome, was formed by the merger of two chimpanzee chromosomes recently renamed chimp chromosomes 2a and 2b.
Matt Ridley wrote in his book Genome that such chromosome fusion may have taken place after a small group of chimps got isolated in northern Africa by a cataclysmic flood some five million years ago. Ridley said that when the primates were "becoming inbred, flirting with extinction, exposed to the forces of the genetic founder effect (by which small population can have large genetic changes thanks to chance), this little band of apes shares a large mutation: two of their chromosomes have become fused. Henceforth they can breed only with their own kind, even when the 'island' rejoins the mainland." The rest, he says, is history.

The Hubble telescope has snapped a fascinating picture of a cannibal galaxy suffering from a bout of indigestion after it devoured a number of smaller peers. The galaxy called NGC 1316 is in the Fornax galaxy cluster 75 million light years away.
"The inner regions of the galaxy shown in the Hubble image reveal a complicated system of dust lanes and patches," Hubble astronomers said. "These are thought to be the remains of the interstellar medium associated with one or more of the spiral galaxies swallowed by NGC 1316" during the last few million years.
The NGC 1316 is a giant elliptical galaxy, not a spiral like the much smaller Milky Way, though it may have started out that way. It swelled out into a gigantic blob of dust and stars after it swallowed its first victim.

Researchers at Stanford University have built a "bionic eye" and started testing the device in rats. They say that the eye's vision is 20/80, sharp enough to recognize faces, watch TV, and read large print letters. They hope that in the future the eye may cure blindness in people with damaged retinas. However, they warned that human trials are at least three years away.
"Currently, there is no effective treatment for most patients with AMD (age-related macular degeneration) and RP (retinitis pigmentosa)," the researchers said. "However, if one could bypass the photoreceptors and directly stimulate the inner retina with visual signals, one might be able to restore some degree of sight."
The artificial eye works by directly stimulating the retinal layer underneath the dead photoreceptors "using a system that looks like a cousin of the high-tech visor blind engineer Lt. Geordi La Forge wore in Star Trek: The Next Generation."
The researchers said that the system consists of a tiny video camera "mounted on transparent 'virtual reality' style goggles." There's also a wallet-sized computer processor, a solar-powered battery implanted in the iris and a half a rice grain-sized light-sensing chip implanted in the retina. The chip allows users to perceive 10 degrees of visual field at a time.
Artificial eyes had already been designed in Germany, Japan, and elsewhere in the U.S. But the Stanford researchers say it achieves the highest clarity by making the most of the eye's natural image-processing strengths by subretinal placement of implants," as well as "tracking rapid intermittent eye movements required for natural image perception."

Astronomers probing the Milky Way with an X-ray satellite telescope have found a gigantic "natural" particle accelerator suspended like a halo above the Arches cluster, the largest star forming region in our galaxy.
Resembling a huge hula hoop, the accelerator has a circumference of some 60 light years. Particles racing on this cosmic autobahn achieve velocities near the speed of light and energies thousand times higher than its earthly counterparts in Brookhaven, Fermilab, or CERN.
Masaaki Sakano from the University of Leicester, U.K. said that most X-ray emissions in the universe are the residual radiation of some cataclysmic event like supernova explosion and have a characteristic temperature. "However, in this case the loop is non-thermal and this means that whatever the origin of the structure is, it is not stationary but rather the result of some ongoing process," Sakano said.
The scientists said that they weren't sure whether the structure was "physically related to the Arches cluster or just happens to be in our line of sight."
The cluster made a splash last month when astronomers studying Arches stars with the Hubble Space Telescopes found that stars have a weight limit: they can't get any fatter than 150 solar masses. (See The Skinny on Fat Stars.)