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Based on the photographic and the CCD observations of the relative motion of A, B components of the binary system ADS~9346 obtained with the 26-inch refractor of the Pulkovo Observatory during 1979-2019, we discover an invisible companion associated with the A-star. Comparison of the ephemerides with the positional and the spectroscopic observations allowed us to calculate the preliminary orbit of the photocenter ($P=15$ years). The minimal mass of the companion is approximately $0.13~M_odot$. The existence of the invisible low-mass companion is implied by the IR-excess based on the IRAS data. To confirm this, additional observations of the radial velocity near the periastron need to be carried out.
We present late-time Hubble Space Telescope (HST) ultraviolet (UV) and optical observations of the site of SN 2011dh in the galaxy M51, ~1164 days post-explosion. At the SN location, we observe a point source that is visible at all wavelengths, that
We present the discovery of a planetary-mass companion to CFHTWIR-Oph 98, a low-mass brown dwarf member of the young Ophiuchus star-forming region, with a wide 200-au separation (1.46 arcsec). The companion was identified using Hubble Space Telescope
The pulsar PSR J1756$-$2251 resides in a relativistic double neutron star (DNS) binary system with a 7.67-hr orbit. We have conducted long-term precision timing on more than 9 years of data acquired from five telescopes, measuring five post-Keplerian
HIP96515A is a double-lined spectroscopic binary with a visual companion (HIP96515B) at 8.6 arcsec. It is included in the SACY catalog as a potential young star and classified as an eclipsing binary in the ASAS Catalog. We have analyzed spectroscopic
The $sim500$, Myr A2IV star HR 1645 has one of the most significant low-amplitude accelerations of nearby early-type stars measured from a comparison of the {it Hipparcos} and {it Gaia} astrometric catalogues. This signal is consistent with either a