- Email: [email protected]
Fart molecule could be next Viagra
KEITH VANDERLINDE/NSF
IN BRIEF Fart molecule could be next Viagra
Ancient supernovae are found frozen in time THE signature of ancient supernova explosions may be written into the ice of Antarctica. The gamma radiation from supernovae is thought to produce nitrogen oxides in the atmosphere, which are then converted to nitrates. As the nitrates could be trapped in snowfall, it is possible that glaciers hold evidence of past supernovae. Yuko Motizuki of the RIKEN research institute in Wako, Japan, and his colleagues took an ice core drilled at Dome Fuji station in Antarctica. They found high nitrate concentrations in three thin layers about 50 metres below the surface (www.arxiv.org/abs/0902.3446). After calibrating this frozen calendar using chemical
markers laid down by known volcanic eruptions, the team found that one nitrate spike was deposited close to the year 1054, when Chinese observers saw a bright supernova. That explosion left behind the Crab nebula and pulsar in the constellation of Orion. Another spike is close to 1006, the year of an even brighter supernova. The third spike, from around 1060, does not coincide with any observed supernova, but Motizuki suggests its light might have been blocked by a dark interstellar cloud. If these results are confirmed by more ice cores, the method could recreate prehistoric skies. “Potentially you could get the supernova rate going back several thousand years,” says Robert Rood of the University of Virginia, Charlottesville, who claimed a similar – but controversial – find in the 1970s. That’s important, because supernovae affect the workings of the whole galaxy, churning up interstellar gas and triggering star formation.
It takes two black holes to tango… HOW heavy can a pair of black holes be and still tango? Try 1 billion solar masses – the combined might of two black holes circling each other at the heart of a quasar 5 billion light years away. A quasar is a galaxy with a supermassive black hole at its centre. Some quasars form when two galaxies merge, so should have two black holes at their 14 | NewScientist | 7 March 2009
cores. But these binary systems are far from easy to find. Todd Boroson and Tod Lauer of the National Optical Astronomy Observatory in Tucson, Arizona, stumbled upon one when they were sifting through a catalogue of 17,500 quasars found by the Sloan Digital Sky Survey. The pair found two sets of broad hydrogen spectral lines in the light coming from J1536+0441,
THE stink of flatulence and rotten eggs could provide a surprising lift for men. Hydrogen sulphide (H2S) causes erections in rats and may one day provide an alternative to Viagra for men. The penis is packed with spongy tissue that produces an erection when it fills with blood. Nitric oxide (NO) helps relax the walls of arteries that supply the penis, allowing extra blood to flow in. Viagra works by blocking an enzyme that destroys NO. H2S has recently been shown to relax the walls of major blood vessels too. Now Giuseppe Cirino at the University of Naples Federico II in Italy and his colleagues have found enzymes that produce H2S in human penile tissue. Injecting this tissue with H2S dilated the blood vessels, while injecting it into the penises of live rats produced erections (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0807974105).
First fossil brain is a fishy discovery
THE first fossil brain ever found is that of a 300-million-year-old fish. Alan Pradel of the French National Natural History Museum in Paris and his team took X-rays of four iniopterygian fish fossils from the Carboniferous period, aiming to infer the size and shape a quasar in the direction of the of the brains from the skulls. constellation Serpens Caput. Pradel was stunned to realise Such signatures are caused by gas that a faint object “like a ghost” swirling into two black holes. “It inside one skull meant that the doesn’t smell like two ordinary brain itself had been preserved quasars along the line of sight,” (Proceedings of the National says Lauer. “This is a good solid Academy of Sciences, DOI: 10.1073/ case of a binary black hole quasar.” pnas.0807047106). The black holes weigh about A film of bacteria seems to 107.3 and 108.9 solar masses, and have coated the brain after death, are separated by about 0.3 light which removed oxygen and years and have an orbital period prevented its degradation, so of nearly 100 years (Nature, DOI: other brains might survive inside 10.1038/nature07779). similarly preserved fossils.
IN BRIEF Fart molecule could be next Viagra
Ancient supernovae are found frozen in time THE signature of ancient supernova explosions may be written into the ice of Antarctica. The gamma radiation from supernovae is thought to produce nitrogen oxides in the atmosphere, which are then converted to nitrates. As the nitrates could be trapped in snowfall, it is possible that glaciers hold evidence of past supernovae. Yuko Motizuki of the RIKEN research institute in Wako, Japan, and his colleagues took an ice core drilled at Dome Fuji station in Antarctica. They found high nitrate concentrations in three thin layers about 50 metres below the surface (www.arxiv.org/abs/0902.3446). After calibrating this frozen calendar using chemical
markers laid down by known volcanic eruptions, the team found that one nitrate spike was deposited close to the year 1054, when Chinese observers saw a bright supernova. That explosion left behind the Crab nebula and pulsar in the constellation of Orion. Another spike is close to 1006, the year of an even brighter supernova. The third spike, from around 1060, does not coincide with any observed supernova, but Motizuki suggests its light might have been blocked by a dark interstellar cloud. If these results are confirmed by more ice cores, the method could recreate prehistoric skies. “Potentially you could get the supernova rate going back several thousand years,” says Robert Rood of the University of Virginia, Charlottesville, who claimed a similar – but controversial – find in the 1970s. That’s important, because supernovae affect the workings of the whole galaxy, churning up interstellar gas and triggering star formation.
It takes two black holes to tango… HOW heavy can a pair of black holes be and still tango? Try 1 billion solar masses – the combined might of two black holes circling each other at the heart of a quasar 5 billion light years away. A quasar is a galaxy with a supermassive black hole at its centre. Some quasars form when two galaxies merge, so should have two black holes at their 14 | NewScientist | 7 March 2009
cores. But these binary systems are far from easy to find. Todd Boroson and Tod Lauer of the National Optical Astronomy Observatory in Tucson, Arizona, stumbled upon one when they were sifting through a catalogue of 17,500 quasars found by the Sloan Digital Sky Survey. The pair found two sets of broad hydrogen spectral lines in the light coming from J1536+0441,
THE stink of flatulence and rotten eggs could provide a surprising lift for men. Hydrogen sulphide (H2S) causes erections in rats and may one day provide an alternative to Viagra for men. The penis is packed with spongy tissue that produces an erection when it fills with blood. Nitric oxide (NO) helps relax the walls of arteries that supply the penis, allowing extra blood to flow in. Viagra works by blocking an enzyme that destroys NO. H2S has recently been shown to relax the walls of major blood vessels too. Now Giuseppe Cirino at the University of Naples Federico II in Italy and his colleagues have found enzymes that produce H2S in human penile tissue. Injecting this tissue with H2S dilated the blood vessels, while injecting it into the penises of live rats produced erections (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0807974105).
First fossil brain is a fishy discovery
THE first fossil brain ever found is that of a 300-million-year-old fish. Alan Pradel of the French National Natural History Museum in Paris and his team took X-rays of four iniopterygian fish fossils from the Carboniferous period, aiming to infer the size and shape a quasar in the direction of the of the brains from the skulls. constellation Serpens Caput. Pradel was stunned to realise Such signatures are caused by gas that a faint object “like a ghost” swirling into two black holes. “It inside one skull meant that the doesn’t smell like two ordinary brain itself had been preserved quasars along the line of sight,” (Proceedings of the National says Lauer. “This is a good solid Academy of Sciences, DOI: 10.1073/ case of a binary black hole quasar.” pnas.0807047106). The black holes weigh about A film of bacteria seems to 107.3 and 108.9 solar masses, and have coated the brain after death, are separated by about 0.3 light which removed oxygen and years and have an orbital period prevented its degradation, so of nearly 100 years (Nature, DOI: other brains might survive inside 10.1038/nature07779). similarly preserved fossils.