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Supermassive "Asteroid Belt" around Star HD 69830
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Caption NASA originale:"This artist's conception illustrates a massive Asteroid Belt in orbit around a star the same age and size as our Sun.
Evidence for this possible belt was discovered by NASA's SST when it spotted warm dust around the star, presumably from asteroids smashing together.
The view starts from outside the belt, where planets like the one shown here might possibly reside, then moves into to the dusty belt itself. Collisions between asteroids replenish the dust in the Asteroid Belt, making it detectable to SST.
The alien belt circles a faint, nearby star called HD 69830 located 41 LY away in the constellation Puppis. Compared to our own Solar System's Asteroid Belt, this one is larger and closer to its star - it is 25 times as massive and lies just inside an orbit which is equivalent to the one of Venus while our Asteroid Belt circles between the orbits of Mars and Jupiter.
Because Jupiter acts as an outer wall to our asteroid belt, shepherding its debris into a series of bands, it is possible that an unseen planet is likewise marshalling this belt's rubble. Previous observations using the radial velocity technique did not locate any large gas giant planets, indicating that any planets present in this system would have to be the size of Saturn or smaller".
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