Their temperatures are ~600,000K, radii 5-15 km, mass ~1.4-3.2 solar masses and extremely low luminosities. Neutron stars are ~0.7% of the stars in the universe. They added that finding more high-mass companions with obliquities measured, around hot stars could be crucial for determining the origins of close-in orbit brown dwarfs like HATS-70b.Neutron stars are produced when the cores of massive stars are compressed past the white dwarf stage during a supernova event. This trend is tentatively inconsistent with dynamically chaotic migration for systems with massive companions, though the stronger tidal influence of these companions makes it difficult to draw conclusions on the primordial obliquity distribution of this population," the authors of the paper wrote. "The low obliquities of these systems is surprising given all brown dwarf and massive planets with obliquities measured orbit stars hotter than the Kraft break. ![]() Such a low obliquity, when it comes to massive objects, still baffles astronomers. The study found that this object, like previously studied massive planets and brown dwarfs, orbits in a low projected-obliquity orbit with 8.9 degrees. Furthermore, HATS-70b is one of few massive planet or brown dwarf systems with a measured obliquity. The researchers emphasized that HATS-70b is the first detected brown dwarf companion transiting an A dwarf star. ![]() The HATS-70 system is located around 4,260 light years away from the sun. The host has an effective temperature of 7,930 K and a luminosity of approximately 12 solar luminosities. With an age of about 810 million years, the parent star is nearly two times larger than the sun and has a mass of around 1.78 solar masses. The brown dwarf resides in a close-in orbit, separated from the host by only 0.036 AU, with an orbital period of 1.89 days. 2013), and confirmed via photometric and spectroscopic follow-up observations that measured the radius and mass of the companion," the researchers wrote in the paper.Īccording to the study, HATS-70b is about 38 percent larger than Jupiter, has a mass of some 12.9 Jupiter masses and an equilibrium temperature of 2,370 K. (…) The transits were first identified by the HATSouth network (Bakos et al. "We report the discovery of HATS-70b, a transiting brown dwarf at the deuterium burning limit. Next, the team conducted follow-up photometric and spectroscopic observations of HATS-70 in order to uncover basic parameters of the companion and its host. The astronomers employed the Hungarian-made Automated Telescope Network-South (HATSouth) to observe HATS-70 and found that this star is transited by some object. Now, a team of researchers led by George Zhou of Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Massachusetts, reports the finding of a new example of a rare brown dwarf companion orbiting an A-type main-sequence (or A dwarf) star known as HATS-70. ![]() Although many brown dwarves have been detected to date, such objects existing as companions of other stars are a rare find. Astronomers generally agree that they are substellar objects occupying the mass range between 13 and 80 Jupiter masses. Brown dwarfs are intermediate objects between planets and stars.
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