binary stars Archives

This artist’s impression illustrates a binary pair of giant stars. Despite being born from the same molecular cloud, astronomers often detect differences in binary stars’ chemical compositions and planetary systems. One star in this system is shown to host three small, rocky planets, while the other star hosts two gas giants. Using Gemini South’s GHOST, a team of astronomers have confirmed for the first time that these differences can be traced back to inhomogeneities in the primordial molecular cloud from which the stars were born. CREDIT NOIRLab/NSF/AURA/J. da Silva (Spaceengine)/M. Zamani

Astrochemistry, Astronomy & Telescopes, Exoplanets, -moons, -comets, Press Release, Stellar Cartography

Gemini South Reveals Origin Of Unexpected Differences In Giant Binary Stars

by Keith CowingApril 30, 2024April 30, 2024

It is estimated that up to 85% of stars exist in binary star systems, some even in systems with three or more stars. These stellar pairs are born together out […]

Upper panel; Left: CCF map for Obs1. Dashed lines and labels: Positions of cuts though the data, shown on the right. Right: Cuts through the data, for different semi-amplitudes (a,b,c), and for the rest velocity of maximum CCF contrast (d); Black dots: data for simulated data-set Obs1, Red line: best fitting Saltire model. Green dashed line: mark of the input semi-amplitude of the EBLM companion. Lower panel; Left: Residual CCF map after removing the Saltire model. Dashed lines and labels: Positions of cuts though the residuals, shown on the right. Right: Cuts through the residuals at similar position as above. Error bars represent uncertainties, derived from 2D Saltire fit to the the CCF map. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

Saltire — A Model To Measure Dynamical Masses For High-contrast Binaries And Exoplanets With High-resolution Spectroscopy

by Keith CowingDecember 4, 2023December 4, 2023

High-resolution cross-correlation methods are widely used to discover and to characterise atomic and molecular species in exoplanet atmospheres. The characteristic cross-correlation signal is typically represented as a function of the […]