Alpha Centauri AB Archives - Astrobiology

These panels represent the Lomb-Scargle power for different activity cycle power frequencies found in the dataset of Alpha Centauri A and B. The highest power for a period > 5 years is marked by the blue dashed line which amounts to 22.2 years for Alpha Centauri A and 8.2 years for Alpha Centauri B. Bottom: These panels represent the sinusoidal fit to the MgII index data for Alpha Centauri A and B. The solar MgII index is overlaid in the figure for reference. The solar MgII index is obtained from the LISIRD website (Leise et al. 2019). -- astro-ph.SR

Alpha Centauri, Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Space Weather & Heliophysics, Status Report, Stellar Cartography

Near UV Stellar Activity and Brightness Fluctuations of the Alpha Centauri AB Star System from Weeks to Decades — Inputs for Reflected Light Spectroscopy with HWO

by Keith CowingMay 27, 2026May 27, 2026

We present the most comprehensive near-ultraviolet (NUV: 2550-3255 Angstrom) activity record to date for the Alpha Centauri AB system, combining archival IUE and HST observations spanning nearly five decades with […]

The strength of indirect detection signals from an Earth-like exoplanet as a function of stellar effective temperature. Bands encompassing main sequence spectral classes A through M color coded by temperature are indicated at the top. Here, Earth-like is defined as a 1-Earth mass object in an orbit receiving irradiance equivalent to 1 AU from our Sun (the solar constant). Radial Velocity signals (solid blue line) are seen to exhibit a rapid rise in signal strength (given on the right-hand abscissa) for cooler, M dwarf systems where they become detectable with present submeter per second RV precision. On the other hand, astrometric deflection signals (colored diamond symbols) rise with host star temperature, and decline linearly with distance from values of up to several microarcseconds for the nearest stars. For convenience the plot also indicates the size of the temperate orbit modeled (in AU, left abscissa) and its corresponding orbital period (in years, also left abscissa). -- astro-ph.IM

Alpha Centauri, Astronomy & Telescopes, Biosignatures & Paleobiology, Cubesats and smallsats, Habitable Zones, Imaging & Spectroscopy, Missions & Hardware, Status Report

The TOLIMAN Mission: A Low-cost Space Telescope For High Precision Narrow-angle Astrometry

by Keith CowingMarch 18, 2026March 18, 2026

The TOLIMAN project is engaged with the construction, launch and operation of a low-cost space telescope of unorthodox optical design. Its primary science goal targets an exhaustive search for temperate-orbit […]

Age of α Centauri A and B estimated in various works. The colors of the points indicate the method: blue, classic method without seismic data; green, seismic analysis; cyan, gyrochronology; orange, chemical analysis; and red, results of this study. -- astro-ph.SR

Alpha Centauri, Astronomy & Telescopes, Status Report, Stellar Cartography

A Mapping Method Of Age Estimation For Binary Stars: Application To The Alpha Centauri System A And B

by Keith CowingFebruary 11, 2026February 11, 2026

Given the wealth of data provided by Gaia and the upcoming PLATO mission, it is essential to improve stellar models to obtain accurate stellar ages. Our objective is to apply […]

This image shows the Alpha Centauri star system from several different ground- and space-based observatories: the Digitized Sky Survey (DSS), the NASA/ESA Hubble Space Telescope, and the NASA/ESA/CSA James Webb Space Telescope. Alpha Centauri A is the third brightest star in the night sky, and the closest Sun-like star to Earth. -- ESA

Alpha Centauri, Astronomy & Telescopes, Exoplanets, -moons, -comets, Gas Giants, Habitable Zones, Imaging & Spectroscopy, Press Release

Webb Finds New Evidence For A Large Planet Orbiting in The Habitable Zone Of Alpha Centauri A

by Keith CowingAugust 7, 2025August 7, 2025

Astronomers using the NASA/ESA/CSA James Webb Space Telescope have found strong evidence of a giant planet orbiting a star in the stellar system closest to our own Sun. At just […]

Alpha Centauri, Exoplanets, -moons, -comets, Gas Giants, Science Fiction, Status Report

Stability of the Potential Super Jupiter in Alpha Centauri System

by Keith CowingJune 28, 2024June 28, 2024

The stability of potential exoplanets in binary star systems remains a critical challenge in celestial mechanics.

Gas column density of the Phantom hydrodynamical simulation of the circumstellar discs in the binary Alpha Centauri. The stars start at apoastron: A is in the top left corner, and B is in the bottom right corner. From left to right and top to bottom, we show the system at different evolutionary stages: 0, 0.5, 1, 1.5, 2.0, 2.5, 3, and 5 Pb , where Pb is a binary orbital period. The red dots represent the stars of Alpha Centauri. -- astro-ph.EP

Alpha Centauri, Exoplanets, -moons, -comets, Proxima Centauri, Status Report

Alpha Centauri: Disc Dynamics, Planet Stability, Detectability

by Keith CowingJanuary 31, 2024January 30, 2024

Alpha Centauri is a triple stellar system, and it contains the closest star to Earth (Proxima Centauri). Over the last decades, the stars in Alpha Cen and their orbits have […]

Alpha Centauri AB

Alpha Centauri, Astronomy & Telescopes, Imaging & Spectroscopy, Press Release, SETI & Technosignatures

A Search For Optical Laser Emission From Alpha Centauri AB

by Keith CowingNovember 23, 2022November 23, 2022

A search for laser light from the directions of Alpha Centauri A and B was performed by examining 15362 optical, high-resolution spectra obtained between 2004 and 2018. None of the […]

Alpha Centauri, Press Release

The Chemical Composition of Alpha Centauri AB Revisited

by Keith CowingMay 3, 2018

The two solar-like stars α Cen A and B have long served as cornerstones for stellar physics in virtue of their immediate proximity, association in a visual binary, and masses […]