Related papers: Keepers of the Double Stars
Fifty years ago, borrowing an idea from our Russian friends Guseinov and Zeldovich, we looked for very compact stars (neutron stars and black holes, in modern terminology) as optically-invisible components of single-line spectroscopic…
Binary stars are dynamical systems formed by two stars that are physically bound by the gravitational force. Binary stars are privileged laboratories, allowing one to measure the fundamental properties of stars but also potentially changing…
As a legacy of the Hubble Space Telescope, a multi-cycle public survey has recently been approved and began to scan an area of approximately 0.5 degrees x 1.5 degrees in one quadrant of M31, using two cameras and several filters. The…
With the discovery of both binary black hole mergers and a binary neutron star merger the field of Gravitational Wave Astrophysics has really begun. The current advanced LIGO and Virgo detectors are laser interferometers that will improve…
The 1982 model for the formation of the Hulse-Taylor binary radio pulsar PSR B1913+16 is described, which since has become the standard model for the formation of double neutron stars, confirmed by the 2003 discovery of the double pulsar…
Since its inception in 1993, the ADS Abstract Service has become an indispensable research tool for astronomers and astrophysicists worldwide. In those seven years, much effort has been directed toward improving both the quantity and the…
The study of pulsars has come a long way since their accidental discovery as ``scruff'' on pen chart recordings of the radio sky at 81 MHz by Jocelyn Bell and Anthony Hewish at Cambridge some thirty years ago. The present sample of almost…
Astrophysical objects below the stellar mass limit but well above the mass of Jupiter eluded discovery for nearly three decades after Kumar first proposed their existence, and for two decades after Tarter proposed the name "brown dwarfs."…
Context. Double eclipsing binaries are gravitationally bound quadruple systems in a 2+2 configuration where both of the binaries are eclipsing. These systems are interesting objects to better understand stellar formation, to investigate the…
Thirty years after the discovery of the first very-high-energy {\gamma}-ray source by the Whipple telescope, the field experienced a revolution mainly driven by the third generation of imaging atmospheric Cherenkov telescopes (IACTs). The…
The 1974 discovery, by Russell A. Hulse and Joseph H. Taylor, of the first binary pulsar PSR B1913+16, opened up new possibilities for the study of relativistic gravity. PSR B1913+16, as well as several other binary pulsars, provided {\it…
I present an overview of the techniques used for detecting and following up binaries in nearby galaxies and present the current census of extragalactic binaries, with a focus on eclipsing systems. The motivation for looking in other…
A large number of direct imaging surveys for exoplanets have been performed in recent years, yielding the first directly imaged planets and providing constraints on the prevalence and distribution of wide planetary systems. However, like…
The uncertainty about the relationships between the star catalogue contained in the Almagest (books VII-VIII) and the catalogue of Hipparchus dates back to the origins of modern astronomy. The fact that Hipparchus' catalogue was lost and…
The comparison of visual magnitudes of stars compiled in old catalogues is expected to yield information about their long-term magnitude variations. In seven old catalogues whose historical data have been intensively compared, 2123 sampled…
Until recently, the only way to observe the Universe was from light received by telescopes. But we are now able to measure gravitational waves, which are ripples in the fabric of the Universe predicted by Albert Einstein. If two very dense…
Close, compact, hierarchical, multiple stellar systems, i.e., multiples having an outer orbital period from months to a few years, comprise a small, but continuously growing group of the triple and multiple star zoo. Many of them consist of…
I present two catalogs. The first one contains the observed and infered data of all of 133 stars wich harbor confirmed extrasolar planets. For these 133 stars I report the following data: stellar mass; spectral type; luminosity class;…
During the 2026 ESO La Silla Observing school, about twenty students attended lectures and performed observations to learn various aspects of observational astronomy. The school, which took place during the first two weeks of February 2026,…
Understanding the formation and evolution of the stellar-mass binary black holes discovered by LIGO and Virgo is a challenge that spans many areas of astrophysics, from stellar evolution, dynamics and accretion disks, to possible exotic…