Talk about a chip off the old block: the meteor that exploded over Chelyabinsk, Russia, last yearMovie Camera was probably spat out during a collision between two much larger rocks more than 290 million years ago, according to new analysis of the meteor's composition.
The meteor is thought to have been about 20 metres wide before it blew up in the atmosphere. Collectors and researchers have recovered a number of fragments in Chelyabinsk, including a large one found at the bottom of a lake, allowing geologists to learn more about its origins.
Previous studies have identified filled-in cracks running through the rock, known as shock veins, produced by high temperature and pressure conditions. They suggest that Chelyabinsk experienced a large impact in its past.
"No other process can be considered to cause such melting after a meteoroid is formed," says Shin Ozawa of Tohoku University in Sendai, Japan.
High pressure
Ozawa and his colleagues examined some of the recovered fragments and found a particular form of the mineral jadeite that seems to have been formed by rapid crystallisation. This would require pressures of between 3 and 12 gigapascals and temperatures of 1700-2000 ºC. From that, they could calculate properties of the impacting body – it was likely to have been between 150 and 190 metres wide and travelling at anything from 1400 to 5400 kilometres an hour.
Previous studies have pinpointed Chelyabinsk's parent as a 200-metre-wide asteroid called 2011 EO40, but this is the first description of the rock that chipped it off.
"The size and velocity of the impactor seem to be consistent with those of impacts in the main asteroid belt," says Ozawa, meaning it was not a freak event that sent Chelyabinsk hurtling our way.
It is also possible that the meteor is one of many siblings formed in the impact, so other large chunks could still be lurking out there. "In some cases, fragments of asteroids formed by an impact can have similar orbits," says Ozawa.
reference : http://www.newscientist.com/article/dn25621-cosmic-collision-created-the-chelyabinsk-meteor.html#.U4rFFHaqJR4
Sabtu, 31 Mei 2014
Cosmic dust bunnies cast the darkest known shadows
The epic dust bunnies lurking within our galaxy are so dark and dense that they cast the darkest shadows ever observed.
Dust marks out cycles of galactic creation and destruction in our cosmos. Grains of carbon and silicon condense in the swollen outer layers of dying stars, or perhaps in the violence of supernova explosions. The grit is blasted out into the surrounding galaxy, where gravity encourages gas to condense around it, forming clouds that eventually collapse and ignite into new generations of stars.
Dust cannot be seen with conventional optical telescopes because it blocks out visible light. In this composite image from NASA's infrared Spitzer Space Telescope, a particularly dark and dense dust cloud in the Milky Way's centre is visible only by the infrared light it blocks from stars behind it. The black shadow it casts – the darkest that NASA has ever recorded – is enough to estimate the cloud's mass at 70,000 times the mass of our sun, spread across a region 50 light years in diameter.
That suggests a briefly glittering future for this galactic cranny. Such a dense cloud would be expected to erupt into a vast clump of giant white-blue stars that will live fast and die young. In their death throes, they will start the cosmic dust-to-dust cycle once again.
reference : http://www.newscientist.com/article/dn25622-cosmic-dust-bunnies-cast-the-darkest-known-shadows.html#.U4rE5naqJR4
Dust marks out cycles of galactic creation and destruction in our cosmos. Grains of carbon and silicon condense in the swollen outer layers of dying stars, or perhaps in the violence of supernova explosions. The grit is blasted out into the surrounding galaxy, where gravity encourages gas to condense around it, forming clouds that eventually collapse and ignite into new generations of stars.
Dust cannot be seen with conventional optical telescopes because it blocks out visible light. In this composite image from NASA's infrared Spitzer Space Telescope, a particularly dark and dense dust cloud in the Milky Way's centre is visible only by the infrared light it blocks from stars behind it. The black shadow it casts – the darkest that NASA has ever recorded – is enough to estimate the cloud's mass at 70,000 times the mass of our sun, spread across a region 50 light years in diameter.
That suggests a briefly glittering future for this galactic cranny. Such a dense cloud would be expected to erupt into a vast clump of giant white-blue stars that will live fast and die young. In their death throes, they will start the cosmic dust-to-dust cycle once again.
reference : http://www.newscientist.com/article/dn25622-cosmic-dust-bunnies-cast-the-darkest-known-shadows.html#.U4rE5naqJR4
Into the methane depths of Kraken Titan's strange sea
A sea of liquid methane laps a shore of solid ice as the biggest rainstorm ever falls from an orange sky. Welcome to Saturn's largest moon
THE sky is a baleful orange, but then it's always like that. The roar of the approaching maelstrom is new though, and disturbing. As are the gathering clouds, which threaten to loose a deluge more violent than anything ever seen on Earth. A sailor on an alien sea may hesitate: is it wise to venture into the Throat of Kraken?
One day this could be a real scene on Saturn's giant moon, Titan. Apart from Earth, Titan is the only world known to have liquid on its surface (see diagram). We first glimpsed its alien lakes and seas through the eyes of the Cassini spacecraft in 2006. Now, after eight years of slow exploration, Cassini has suddenly unleashed a flood of ...
To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.
reference : http://www.newscientist.com/article/mg22229700.800-into-the-methane-depths-of-kraken-titans-strange-sea.html
THE sky is a baleful orange, but then it's always like that. The roar of the approaching maelstrom is new though, and disturbing. As are the gathering clouds, which threaten to loose a deluge more violent than anything ever seen on Earth. A sailor on an alien sea may hesitate: is it wise to venture into the Throat of Kraken?
One day this could be a real scene on Saturn's giant moon, Titan. Apart from Earth, Titan is the only world known to have liquid on its surface (see diagram). We first glimpsed its alien lakes and seas through the eyes of the Cassini spacecraft in 2006. Now, after eight years of slow exploration, Cassini has suddenly unleashed a flood of ...
To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.
reference : http://www.newscientist.com/article/mg22229700.800-into-the-methane-depths-of-kraken-titans-strange-sea.html
It's crunch time for dark matter if WIMPs don't show
If dark matter isn't made of WIMPs, could neutrinos or axions fit the bill? What if it's not a particle at all but a strange modification of gravity?
ROADS may soon diverge in the dark matter wood, and some physicists want to take the ones less travelled.
The most promising candidate for a dark matter particle could be about to show itself at last, as it is running out of places to hide. But should the hunters fail to bag one of these WIMPs, or weakly interacting massive particles, the search for dark matter could be thrown into crisis.
At a meeting in Cambridge, Massachusetts, last week, researchers debated the best paths forward into the wilder landscape of less-favoured candidates, from alternate particles to changes to our theory of gravity.
"It's really refreshing," says Lisa Randall at Harvard University. "For years I went to conferences where people said, 'We know what dark matter is and we're just cutting out the parameter space'. I thought that was strange, because we really don't know what dark matter is."
So far we have only sensed dark matter's presence through its gravitational effects. But theory says that WIMPs should also brush shoulders with normal atoms occasionally, producing signals we can detect. WIMP champions are pinning their hopes on more sensitive underground detectors that are running or under construction.
"This is a golden decade for dark matter because of detector sensitivity," says Kathryn Zurek at the University of Michigan in Ann Arbor.
The trouble is that background noise can prevent usnoticing the impact of a WIMP. Beyond a certain sensitivity limit, the signal would be swamped by neutrinos, nearly massless particles that are constantly streaming from the sun and from particle collisions in our atmosphere. After just a few more upgrades, WIMP hunters will hit this limit and the desired particles may no longer be detectable.
Indirect methods for spotting WIMPs offer the best chance of a sighting. When WIMPs collide they should annihilate, shattering into other particles. This includes gamma rays, and an excess of these high-energy photons spotted in the centre of our galaxy seems to fit nicely with the simplest models for WIMPs. But one criticism is that the rays could just as easily come from fast-spinning dead stars called pulsars.
So if not WIMPs then what? Some theories modify the classic particle, changing its properties and offering new places to look. Others focus more on runner-up particles, such as axions or sterile neutrinos. And still others say dark matter might not exist at all, and we just need to modify the laws of gravity (see right).
"It's always possible WIMPs are just around the corner," says Avi Loeb at Harvard University. "But when there is no evidence, you have to be careful. We're looking for a black cat in a dark room."
reference : http://www.newscientist.com/article/mg22229712.600-its-crunch-time-for-dark-matter-if-wimps-dont-show.html#.U4rEXnaqJR4
ROADS may soon diverge in the dark matter wood, and some physicists want to take the ones less travelled.
The most promising candidate for a dark matter particle could be about to show itself at last, as it is running out of places to hide. But should the hunters fail to bag one of these WIMPs, or weakly interacting massive particles, the search for dark matter could be thrown into crisis.
At a meeting in Cambridge, Massachusetts, last week, researchers debated the best paths forward into the wilder landscape of less-favoured candidates, from alternate particles to changes to our theory of gravity.
"It's really refreshing," says Lisa Randall at Harvard University. "For years I went to conferences where people said, 'We know what dark matter is and we're just cutting out the parameter space'. I thought that was strange, because we really don't know what dark matter is."
So far we have only sensed dark matter's presence through its gravitational effects. But theory says that WIMPs should also brush shoulders with normal atoms occasionally, producing signals we can detect. WIMP champions are pinning their hopes on more sensitive underground detectors that are running or under construction.
"This is a golden decade for dark matter because of detector sensitivity," says Kathryn Zurek at the University of Michigan in Ann Arbor.
The trouble is that background noise can prevent usnoticing the impact of a WIMP. Beyond a certain sensitivity limit, the signal would be swamped by neutrinos, nearly massless particles that are constantly streaming from the sun and from particle collisions in our atmosphere. After just a few more upgrades, WIMP hunters will hit this limit and the desired particles may no longer be detectable.
Indirect methods for spotting WIMPs offer the best chance of a sighting. When WIMPs collide they should annihilate, shattering into other particles. This includes gamma rays, and an excess of these high-energy photons spotted in the centre of our galaxy seems to fit nicely with the simplest models for WIMPs. But one criticism is that the rays could just as easily come from fast-spinning dead stars called pulsars.
So if not WIMPs then what? Some theories modify the classic particle, changing its properties and offering new places to look. Others focus more on runner-up particles, such as axions or sterile neutrinos. And still others say dark matter might not exist at all, and we just need to modify the laws of gravity (see right).
"It's always possible WIMPs are just around the corner," says Avi Loeb at Harvard University. "But when there is no evidence, you have to be careful. We're looking for a black cat in a dark room."
reference : http://www.newscientist.com/article/mg22229712.600-its-crunch-time-for-dark-matter-if-wimps-dont-show.html#.U4rEXnaqJR4
Space hopefuls dine on worms in 'Moon Palace' module
Maybe there's a reason we call them mealworms. Three volunteers in China have just spent three months eating beetle larvae as part of a project to test life-support systems for deep-space travel.
Last week, one man and two women emerged from Moon Palace 1, an artificial biosphere at the Beijing University of Aeronautics and Astronautics. The 160-square-metre capsule is designed to test self-sustaining technologies that may one day be used on a long-duration mission.
The volunteers grew and harvested grain, vegetables and fruit, feeding the inedible leftovers to mealworms. Along with some meat, the mock crew ate dozens of mealworms each day, trying out different seasonings and cooking styles. The results of the trial have not yet been published, but the volunteers seemed to be healthy and happy after adjusting to the new diet, says Hong Liu, the lead researcher on the project.
"Mealworms have good nutritional components, high protein value and a good composition of essential amino acids," Liu added. A previous analysis by the team published in 2013 found that each worm was about 76 per cent protein and 6 per cent fat.
Escape artists
An experiment on the International Space Station may soon be producing fresh vegetables for astronauts, and projects on Earth are championing insects as a food source. But the jury is still out on whether mealworms will make an acceptable space snack.
Story Musgrave, a former NASA astronaut who is also an expert in aerospace medicine, has few concerns. "Meat is meat," he says. Yet raising any kind of animal in space is a difficult prospect.
Kim Binsted at the University of Hawaii works on HI-SEAS, another project that simulates long trips to space. Her team also considered growing mealworms for food, but ran into problems: "In the end we decided against it, because apparently they're little escape artists." And mealworms might not be the first choice for an extraterrestrial protein source. Brian Ratcliffe, a nutrition scientist at Robert Gordon University in Aberdeen, UK, thinks that freshwater algae such as spirulina could offer many of the same benefits as mealworms, but would be easier to wrangle.
reference : http://www.newscientist.com/article/dn25641-space-hopefuls-dine-on-worms-in-moon-palace-module.html#.U4rEMHaqJR4
Last week, one man and two women emerged from Moon Palace 1, an artificial biosphere at the Beijing University of Aeronautics and Astronautics. The 160-square-metre capsule is designed to test self-sustaining technologies that may one day be used on a long-duration mission.
The volunteers grew and harvested grain, vegetables and fruit, feeding the inedible leftovers to mealworms. Along with some meat, the mock crew ate dozens of mealworms each day, trying out different seasonings and cooking styles. The results of the trial have not yet been published, but the volunteers seemed to be healthy and happy after adjusting to the new diet, says Hong Liu, the lead researcher on the project.
"Mealworms have good nutritional components, high protein value and a good composition of essential amino acids," Liu added. A previous analysis by the team published in 2013 found that each worm was about 76 per cent protein and 6 per cent fat.
Escape artists
An experiment on the International Space Station may soon be producing fresh vegetables for astronauts, and projects on Earth are championing insects as a food source. But the jury is still out on whether mealworms will make an acceptable space snack.
Story Musgrave, a former NASA astronaut who is also an expert in aerospace medicine, has few concerns. "Meat is meat," he says. Yet raising any kind of animal in space is a difficult prospect.
Kim Binsted at the University of Hawaii works on HI-SEAS, another project that simulates long trips to space. Her team also considered growing mealworms for food, but ran into problems: "In the end we decided against it, because apparently they're little escape artists." And mealworms might not be the first choice for an extraterrestrial protein source. Brian Ratcliffe, a nutrition scientist at Robert Gordon University in Aberdeen, UK, thinks that freshwater algae such as spirulina could offer many of the same benefits as mealworms, but would be easier to wrangle.
reference : http://www.newscientist.com/article/dn25641-space-hopefuls-dine-on-worms-in-moon-palace-module.html#.U4rEMHaqJR4
SpaceX unveils sleek reusable Dragon crew capsule
First cargo, now crew – the uber-modern "space taxi" known as the Dragon V2 is ready for passengers. At an unveiling ceremony yesterday, complete with smoke effects and coloured lights, SpaceX CEO Elon Musk gave the world its first glimpse of the upgraded Dragon spacecraft.
NASA is already using an unpiloted version of Dragon to send cargo to the International Space Station and return valuable gear and scientific experiments. But Musk has always wanted Dragon to become a reusable ride for astronauts.
The new vehicle has simple silvery walls, seats for up to seven passengers and a set of flatscreen control panels. The spacecraft can dock itself to the ISS without help from the space station's robotic arm. But the most radical aspect of the redesign is the landing gear, which will allow astronauts to set the spacecraft down on solid ground.
Space chopper
The current version of Dragon deploys a parachute as it descends and splashes down in the ocean. Dragon V2 instead comes with a set of incredibly powerful SuperDraco engines, each capable of producing more than 70,000 newtons of thrust. The engines will allow astronauts to better manoeuvre in space as well as control their trajectory for re-entry.
"You'll be able to land anywhere on Earth with the accuracy of a helicopter," Musk said during the event at SpaceX headquarters in Hawthorne, California. The engines are encased in protective shells, and they are set up in pairs so that if one fails, the other can give a boost of power to compensate.
The Dragon V2 also has sturdier heat shields, which brings SpaceX a step closer to realising its goal of developing spacecraft that are fully and rapidly reusable. SpaceX has successfully tested a set of landing legs on a rocket used to send the uncrewed Dragon to the ISS, and Musk hopes to soon make it possible for rockets and crew capsules to simply be reloaded with propellant and flown again, much like commercial airplanes.
"As long as we continue to throw away rockets and spacecraft, we will never have true access to space," says Musk.
Rodent crew
Like passengers in today's commercial aeroplanes, riders of the Dragon V2 won't get much leg room in the capsule's tight quarters. But the craft does include touchscreen interfaces to control the spacecraft, as well as manual buttons for critical functions that would be needed in case of emergency.
NASA astronauts are not set to ride in the Dragon V2 until 2017. However, a colony of mice and rats will make the journey on the next SpaceX cargo launch, becoming the private company's first mammalian passengers.
The rodents are set to spend six months on the ISS and will be the subjects of various experiments on the long-term effects of microgravity on mammal physiology. The results will hopefully prove handy for Musk, who hopes to eventually shuttle humans on the long trip to MarsMovie Camera.
When the Dragon V2 does launch with its first commercial crew, the face of space travel is going to change. "It will no longer be heroic to go to space – it will become a commodity – and it's about time," says John Logsdon, a space policy expert at George Washington University's Elliott School of International Affairs in Washington DC. "What will count is what people do once they get there."
reference : http://www.newscientist.com/article/dn25652-spacex-unveils-sleek-reusable-dragon-crew-capsule.html#.U4rDyHaqJR4
NASA is already using an unpiloted version of Dragon to send cargo to the International Space Station and return valuable gear and scientific experiments. But Musk has always wanted Dragon to become a reusable ride for astronauts.
The new vehicle has simple silvery walls, seats for up to seven passengers and a set of flatscreen control panels. The spacecraft can dock itself to the ISS without help from the space station's robotic arm. But the most radical aspect of the redesign is the landing gear, which will allow astronauts to set the spacecraft down on solid ground.
Space chopper
The current version of Dragon deploys a parachute as it descends and splashes down in the ocean. Dragon V2 instead comes with a set of incredibly powerful SuperDraco engines, each capable of producing more than 70,000 newtons of thrust. The engines will allow astronauts to better manoeuvre in space as well as control their trajectory for re-entry.
"You'll be able to land anywhere on Earth with the accuracy of a helicopter," Musk said during the event at SpaceX headquarters in Hawthorne, California. The engines are encased in protective shells, and they are set up in pairs so that if one fails, the other can give a boost of power to compensate.
The Dragon V2 also has sturdier heat shields, which brings SpaceX a step closer to realising its goal of developing spacecraft that are fully and rapidly reusable. SpaceX has successfully tested a set of landing legs on a rocket used to send the uncrewed Dragon to the ISS, and Musk hopes to soon make it possible for rockets and crew capsules to simply be reloaded with propellant and flown again, much like commercial airplanes.
"As long as we continue to throw away rockets and spacecraft, we will never have true access to space," says Musk.
Rodent crew
Like passengers in today's commercial aeroplanes, riders of the Dragon V2 won't get much leg room in the capsule's tight quarters. But the craft does include touchscreen interfaces to control the spacecraft, as well as manual buttons for critical functions that would be needed in case of emergency.
NASA astronauts are not set to ride in the Dragon V2 until 2017. However, a colony of mice and rats will make the journey on the next SpaceX cargo launch, becoming the private company's first mammalian passengers.
The rodents are set to spend six months on the ISS and will be the subjects of various experiments on the long-term effects of microgravity on mammal physiology. The results will hopefully prove handy for Musk, who hopes to eventually shuttle humans on the long trip to MarsMovie Camera.
When the Dragon V2 does launch with its first commercial crew, the face of space travel is going to change. "It will no longer be heroic to go to space – it will become a commodity – and it's about time," says John Logsdon, a space policy expert at George Washington University's Elliott School of International Affairs in Washington DC. "What will count is what people do once they get there."
reference : http://www.newscientist.com/article/dn25652-spacex-unveils-sleek-reusable-dragon-crew-capsule.html#.U4rDyHaqJR4
Ultimate solar system could contain 60 Earths
Why settle for one habitable planet, when you can have 60? An astrophysicist has designed the ultimate star system by cramming in as many Earth-like worlds as possible without breaking the laws of physics. Such a monster cosmic neighbourhood is unlikely to exist in reality, but it could inspire future exoplanet studies.
Sean Raymond of Bordeaux Observatory in France started his game of fantasy star system with a couple of ground rules. First, the arrangement of planets must be scientifically plausible. Second, they must be gravitationally stable over billions of years: there is no point in putting planets into orbit only to watch them spiral into the sun.
"The arguments were based on the recent scientific literature as well as some simple calculations I did," says Raymond. In some cases it was impossible to choose between two scenarios because of a lack of data, so he just picked the one he liked best.
To start with he chose a red dwarf star as the system's host because they have a lower mass than stars like our sun and so live longer, giving a stable habitable zone – the region around a star in which liquid water can exist.
Next, he used a couple of tricks to boost the planetary potential of his system. An Earth-sized planet can also have an almost Earth-sized moon, with the two worlds orbiting around a central point. What's more, two pairs of planets can orbit a star at the same distance, provided that they are separated by 60 degrees, thanks to a couple of gravitationally stable points. In our solar system these points are normally inhabited by asteroids, rather than planets, but nothing rules out a multiple planet scenario. Objects in this configuration are known as Trojans – Jupiter has thousands, and even Earth has one.
There is room for six of these orbital configurations in the habitable zone of a red dwarf, giving a total of 24 habitable planets in one system. But it turns out there is also another way to build a packed system: Jupiters.
Gas giants such as Jupiter are not habitable to life as we know it, but they can be orbited by Earth-like moons. In our solar system, Europa and Enceladus, which orbit Jupiter and Saturn, respectively, are prime candidates for extraterrestrial life. Raymond calculates that a red dwarf could hold four Jupiter-like planets, each with five Earth-like moons. What's more, the Trojan trick can allow another two Earth-like planets on either side of the orbiting Jupiters, upping the total number of habitable worlds around the red dwarf to 36.
Finally, Raymond turned his star system into a binary one, with two red dwarfs separated by roughly the distance from our sun to the edge of the solar system. Theory allows one star to carry the Earth-only configuration, and the other to carry the Earth-plus-Jupiters configuration. This creates the ultimate star system, with 60 habitable planets to choose from.
"It is thought provoking," says Mikko Tuomi of the University of Hertfordshire in Hatfield, UK, who helped to discover the star system with the largest number of known planets, but the odds of something like it actually forming in the real universe are slim to none. "This would be due to the lack of matter at or near the habitable zone in the accretion disk from which planets form," says Tuomi. Sufficiently advanced aliens could build a system like this, he says, but it is not clear why they would bother.
"I admit that it would be extremely fortuitous for nature to produce a system that was so spectacular," says Raymond. "Still, each piece of the system is plausible and even expected from simulations of planetary formation."
Coming up with the system has also thrown up new scientific questions, he says. "I ended up doing a lot of research into the different pieces of the puzzle, and coming at it from this point of view gave me some new ideas I'm planning to test in the future."
reference : http://www.newscientist.com/article/dn25653-ultimate-solar-system-could-contain-60-earths.html#.U4rDJHaqJR4
Sean Raymond of Bordeaux Observatory in France started his game of fantasy star system with a couple of ground rules. First, the arrangement of planets must be scientifically plausible. Second, they must be gravitationally stable over billions of years: there is no point in putting planets into orbit only to watch them spiral into the sun.
"The arguments were based on the recent scientific literature as well as some simple calculations I did," says Raymond. In some cases it was impossible to choose between two scenarios because of a lack of data, so he just picked the one he liked best.
To start with he chose a red dwarf star as the system's host because they have a lower mass than stars like our sun and so live longer, giving a stable habitable zone – the region around a star in which liquid water can exist.
Next, he used a couple of tricks to boost the planetary potential of his system. An Earth-sized planet can also have an almost Earth-sized moon, with the two worlds orbiting around a central point. What's more, two pairs of planets can orbit a star at the same distance, provided that they are separated by 60 degrees, thanks to a couple of gravitationally stable points. In our solar system these points are normally inhabited by asteroids, rather than planets, but nothing rules out a multiple planet scenario. Objects in this configuration are known as Trojans – Jupiter has thousands, and even Earth has one.
There is room for six of these orbital configurations in the habitable zone of a red dwarf, giving a total of 24 habitable planets in one system. But it turns out there is also another way to build a packed system: Jupiters.
Gas giants such as Jupiter are not habitable to life as we know it, but they can be orbited by Earth-like moons. In our solar system, Europa and Enceladus, which orbit Jupiter and Saturn, respectively, are prime candidates for extraterrestrial life. Raymond calculates that a red dwarf could hold four Jupiter-like planets, each with five Earth-like moons. What's more, the Trojan trick can allow another two Earth-like planets on either side of the orbiting Jupiters, upping the total number of habitable worlds around the red dwarf to 36.
Finally, Raymond turned his star system into a binary one, with two red dwarfs separated by roughly the distance from our sun to the edge of the solar system. Theory allows one star to carry the Earth-only configuration, and the other to carry the Earth-plus-Jupiters configuration. This creates the ultimate star system, with 60 habitable planets to choose from.
"It is thought provoking," says Mikko Tuomi of the University of Hertfordshire in Hatfield, UK, who helped to discover the star system with the largest number of known planets, but the odds of something like it actually forming in the real universe are slim to none. "This would be due to the lack of matter at or near the habitable zone in the accretion disk from which planets form," says Tuomi. Sufficiently advanced aliens could build a system like this, he says, but it is not clear why they would bother.
"I admit that it would be extremely fortuitous for nature to produce a system that was so spectacular," says Raymond. "Still, each piece of the system is plausible and even expected from simulations of planetary formation."
Coming up with the system has also thrown up new scientific questions, he says. "I ended up doing a lot of research into the different pieces of the puzzle, and coming at it from this point of view gave me some new ideas I'm planning to test in the future."
reference : http://www.newscientist.com/article/dn25653-ultimate-solar-system-could-contain-60-earths.html#.U4rDJHaqJR4
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