اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدOn the enlargement of habitable zones around binary stars in hostile environments
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We investigate the hypothesis that the size of the habitable zone around hardened binaries in dense star-forming regions increases. Our results indicate that this hypothesis is essentially incorrect. Although certain binary star configurations permit extended habitable zones, such setups typically require all orbits in a system to be near circular. In all other cases planets can only remain habitable if they display an extraordinarily high climate inertia.
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Habitable zones are regions around stars where large bodies of liquid water can be sustained on a planet or satellite. As many stars form in binary systems with non-zero eccentricity, the habitable zones around the component stars of the binary can o
verlap and be enlarged when the two stars are at periastron (and less often when the stars are at apastron). We perform N-body simulations of the evolution of dense star-forming regions and show that binary systems where the component stars originally have distinct habitable zones can undergo interactions that push the stars closer together, causing the habitable zones to merge and become enlarged. Occasionally, overlapping habitable zones can occur if the component stars move further apart, but the binary becomes more eccentric. Enlargement of habitable zones happens to 1-2 binaries from an average initial total of 352 in each simulated star-forming region, and demonstrates that dense star-forming regions are not always hostile environments for planet formation and evolution.
Identifying terrestrial planets in the habitable zones (HZs) of other stars is one of the primary goals of ongoing radial velocity and transit exoplanet surveys and proposed future space missions. Most current estimates of the boundaries of the HZ ar
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Several concepts have been brought forward to determine where terrestrial planets are likely to remain habitable in multi-stellar environments. Isophote-based habitable zones, for instance, rely on insolation geometry to predict habitability, whereas
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