Exoplanet debris in the binary star system

Binary star system SDSS 1557 is about one thousand light years away. It consists of white dwarf and brown dwarf, almost as in Tatooine system in Star Wars. New study, published in Nature Astronomy, reports on the remains of shattered rocky asteroids orbiting two star system. In fact, astronomers discovered in white dwarf's spectrum traces of heavy elements, such as silicon and magnesium.

Image: AstronomyNow

This means that (as scientists suggest) rocky planets as Tatooine might exist in such systems. One feature of white dwarves is that all elements, heavier than hydrogen and helium cannot stay for long on star's surface and sinks to the core. So, white dwarf was recently polluted by rocky/metal body. Evaluations show that mass of this body was about 1,1 trillion tons, which corresponds 4 kilometers asteroid. To date, all exoplanets, discovered in double systems were gas giants. Observations show that all system is surrounded by dusty disk, probably from silicon and metals too. In our system, asteroid belt consists of building block from which inner planets (Mercury, Venus, Earth, Mars) were built. So dusty disk might consist of such blocks or remains of rocky planet, torn by two stars gravity.

Image: NASA

 Professor Boris Gänsicke (University of Warwick) analysed these data and found they all told a consistent and compelling story:

 We’ll be looking at SDSS 1557 next with Hubble, to conclusively show the dust is made of rock rather than ice 

Only one thing bothers me: Tatooine had two full scale suns:

Besides, the rocky planet, destroyed by the Death Star was Alderaan!!