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The strange solar system, discovered not too far from our own, forces astronomers to reconsider their ideas about how the planets are created.
In the journal Science researchers report that they have discovered a small, dark red dwarf star, about 30 light-years from Earth, drawn by the weight of what must be a huge planet like Jupiter.
"It's a very big planet, for such a small star," says Juan Carlos Morales, an astrophysicist at the Space Research Institute of Catalonia in Barcelona who was part of the research team.
He is so great, he says, that his existence cannot be explained by conventional wisdom about how solar systems develop.
"This is a surprising thing," says Morales. "We need another alternative formation scenario to explain this system."
Newborn stars are temporarily surrounded by a rotating disc of residual gas and dust. Scientists have long believed that planets begin to grow when pieces of hard material in this disk begin to collide and assemble together.
These growing bodies can eventually become rocky planets. Or they can become rocky, ice cores that capture rotating gases and turn into Jupiter-like giants.
This basic understanding is maintained even as astronomers have discovered thousands of planets around distant stars in recent years. The vast array of known worlds includes gas giants, Earth-sized planets that could be rocky, and planets sized unlike anything else in our own solar system.
All of these could theoretically be explained by the traditional "basic accent" or by glamming together, a model for building a planet – so far. "For the first time, we are sure that we have a planet that we cannot explain with the model of the nucleus of accretion," Morales says.
But there is another idea that could potentially explain this planet, the less popular one that has been around since 1997. The astronomer who came up with it, Alan Boss of the Carnegie Institute of Science in Washington, DC , says he "wasn't really taken too many by the people."
More than two decades ago, while thinking of all the different ways in which a rotating disc of gas and dust could be held, the boss realized that areas of the disc could form dense lumps that could spontaneously shrink and to crash into planets.
"This can happen in something like 100 years," says the boss.
Gradually sticking enough material piece by piece to form a planet can take, say, a million years or more – too long to create a Jupiter-sized planet around a low-mass star like red a dwarf in this study, says the boss.
This is because the creation of such a foggy star would leave only a dull disk of dust and gas moving at a snail's pace and eventually disappearing. "Nothing just happens over the period that we believe these discs continue," Boss explains. "You just miss the time."
But this may be possible in his scenario for the rapid creation of a planet. And he was pleased to learn that there was now evidence that this could actually happen in the universe.
"I'm still a little shocked that someone actually thinks my ideas have some merit," the boss says, laughing. "I'm sure I'll overcome it, but it's very enjoyable."
Courtney Dressing, an astronomer at the University of California at Berkeley, says this find of a new planet and its consequences are exciting.
She says that the planet was discovered only because the research team used a new tool that can detect worlds orbiting relatively far from reddish stars.
"I think this is probably just the tip of the iceberg," says Dressing, "I think the knowledge that these objects exist will make us think more closely about how these planets formed in the first place. "
Scientists partially study planets outside our solar system because "you never know if you find one, it just reverses a trend that's new and exciting in some way that sheds light on the problem in planetary science," says Sarah Seiger, an astrophysicist and a planetary scientist at MIT. "And I think this one really fits that category.
She says that there are often several competing hypotheses in science to explain a phenomenon, such as how planets are created.
" It often turns out that both paradigms or both are actually correct, "Seager notes. "Nature is smarter than we are. And probably if we humans can imagine something going on, it's probably happening."