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Extrasolar enigmas: from disintegrating exoplanets to exoasteroids

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 نشر من قبل Jan Budaj
 تاريخ النشر 2020
  مجال البحث فيزياء
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Thousands of transiting exoplanets have been discovered to date, thanks in great part to the {em Kepler} space mission. As in all populations, and certainly in the case of exoplanets, one finds unique objects with distinct characteristics. Here we will describe the properties and behaviour of a small group of `disintegrating exoplanets discovered over the last few years (KIC 12557548b, K2-22b, and others). They evaporate, lose mass unraveling their naked cores, produce spectacular dusty comet-like tails, and feature highly variable asymmetric transits. Apart from these exoplanets, there is observational evidence for even smaller `exo-objects orbiting other stars: exoasteroids and exocomets. Most probably, such objects are also behind the mystery of Boyajians star. Ongoing and upcoming space missions such as {em TESS} and PLATO will hopefully discover more objects of this kind, and a new era of the exploration of small extrasolar systems bodies will be upon us.



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