How dusty is alpha Centauri? Excess or non-excess over the infrared photospheres of main-sequence stars

  title={How dusty is alpha Centauri? Excess or non-excess over the infrared photospheres of main-sequence stars},
  author={J. Wiegert and Ren{\'e} Liseau and Ph. Th'ebault and G{\"o}ran Olofsson and Andr{\'e} Mora and Geoffrey C. Bryden and Jonathan P. Marshall and Carlos Eiroa and Benjamı́n Montesinos and David R. Ardila and J. Ch. Augereau and A. Aran and William C. Danchi and Carlos del Burgo and Steve Ertel and Malcolm Fridlund and Mitra Hajigholi and Alexander V. Krivov and G{\"o}ran Pilbratt and Aki Roberge and Glenn J. White and S. Earth and Space Sciences and Chalmers University of Technology and Sweden. and Observatoire de Paris and Laboratoire d''etudes spatiales et d'instrumentation en astrophysique and France. and Department of Astronomy and Stockholm University and Esa - Esac Gaia SOC. P.O. and Spain. and Jet Propulsion Laboratory and Usa and Departamento de F'isica Te'orica and C-XI and Facultad de Ciencias and Universidad Aut'onoma de Madrid and Departamento de Astrof'isica and Centro de Astrobiolog'ia and Nasa Herschel Science Center and Infrared Processing and Analysis Center and California Institute of Technology Herschel Science Center and European Space Agency and European Space Astronomy Centre and 1 UJF-Grenoble and CNRS-INSU and Institut de Plan'etologie et d'Astrophysique de Grenoble and European Southern Observatory and Chile. and Max-Planck-Institut fur Astronomie and H Germany and Astrophysics Science Division and Nasa Goddard Space Flight Center and Instituto Nacional de Astrof'isica and 'optica y Electr'onica and M'exico. and Institute of planetary Research and German Aerospace Center and Leiden Observatory and University of Leiden and The Netherlands. and Astrophysikalisches Institut und Universitatssternwarte and Friedrich-Schiller-Universitat Jena and Astrophysics Mission Division and Research and Scientific Support Department Esa and Exoplanets and Stellar Astrophysics Laboratory and Dept. of PhysicsAstronomy and UK TheOpenUniversity and Space ScienceTechnology Department and Cclrc Rutherford Appleton Laboratory and UK. and Institute for Particle Physics and Astrophysics and University of Kiel},
  journal={Astronomy and Astrophysics},
Context. Debris discs around main-sequence stars indicate the presence of larger rocky bodies. The components of the nearby, solar-type binary alpha Centauri have metallicities that are higher than solar, which is thought to promote giant planet formation. Aims. We aim to determine the level of emission from debris around the stars in the alpha Cen system. This requires knowledge of their photospheres. Having already detected the temperature minimum, Tmin , of alpha Cen A at far-infrared… 

ALMA observations of α Centauri - First detection of main-sequence stars at 3 mm wavelength

Context. The precise mechanisms that provide the non-radiative energy for heating the chromosphere and the corona of the Sun and those of other stars constitute an active field of research. By

Imaging low-mass planets within the habitable zone of α Centauri

Sensitivity to warm sub-Neptune-sized planets throughout much of the habitable zone of α Centauri A is demonstrated, an order of magnitude more sensitive than state-of-the-art exoplanet imaging mass detection limits.

Searching for Planets Orbiting α Cen A with the James Webb Space Telescope

α Centauri A is the closest solar-type star to the Sun and offers an excellent opportunity to detect the thermal emission of a mature planet heated by its host star. The MIRI coronagraph on the James

The chemical composition of α Centauri AB revisited

  • T. Morel
  • Physics, Geology
    Astronomy & Astrophysics
  • 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 that bracket that of the


Fomalhaut plays an important role in the study of debris disks and small bodies in other planetary systems. The proximity and luminosity of the star make key features of its debris, like the water

Incidence of debris discs around FGK stars in the solar neighbourhood

Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their solar system's counterparts are the asteroid and Edgeworth-Kuiper belts.

94 Ceti: a triple star with a planet and dust disc

94 Ceti is a triple star system with a circumprimary gas giant planet and far-infrared excess. Such excesses around main sequence stars are likely due to debris discs, and are considered as signposts

How to directly image a habitable planet around Alpha Centauri with a ~30-45cm space telescope

Several mission concepts are being studied to directly image planets around nearby stars. It is commonly thought that directly imaging a potentially habitable exoplanet around a Sun-like star

High contrast imaging in multi-star systems: technology development and first lab results

We show preliminary laboratory results advancing the technology readiness of a method to directly image planets and disks in multi-star systems such as Alpha Centauri. This method works with almost

Imaging Earth-like Exoplanets with a Small Space Telescope

The Cen AB system represents a particularly attractive target for missions to directly image exoplanets. A potentially habitable planet can in theory be imaged in the system with a telescope as



α Centauri A in the far infrared: First measurement of the temperature minimum of a star other than the Sun

Context. Chromospheres and coronae are common phenomena on solar-type stars. Understanding the energy transfer to these heated atmospheric layers requires direct access to the relevant empirical

Debris discs around M stars: non-existence versus non-detection

Motivated by the reported dearth of debris discs around M stars, we use survival models to study the occurrence of planetesimal discs around them. These survival models describe a planetesimal disc

BETA PICTORIS: An Early Solar System?

Beta Pictoris ( Pic) is the best studied of the normal main-sequence stars surrounded by circumstellar dust disks. We review the status of Pic and its disk, and compare it with both the early and the


Infrared excesses associated with debris disk host stars detected so far peak at wavelengths around ∼100 μm or shorter. However, 6 out of 31 excess sources studied in the Herschel Open Time Key


We present 24 μm and 70 μm Multiband Imaging Photometer for Spitzer (MIPS) observations of 70 A through M-type dwarfs with estimated ages from 8 Myr to 1.1 Gyr, as part of a Spitzer guaranteed time

Formation and Detectability of Terrestrial Planets around α Centauri B

We simulate the formation of planetary systems around α Centauri B. The N-body accretionary evolution of a Σ ∝ r−1 disk populated with 400-900 lunar-mass protoplanets is followed for 200 Myr. All

Stellar model chromospheres. V - Alpha Centauri A /G2 V/ and Alpha Centauri B /K1 V/

We propose models for the upper photospheres and lower chromospheres of ..cap alpha.. Cen A and B based on a partial redistribution (PRD) analysis of the Ca II K line cores and damping wings. Coude

A DEBRIS disk around the planet hosting M-star GJ 581 spatially resolved with Herschel

Debris disks have been found primarily around intermediate and solar mass stars (spectral types A-K) but rarely around low mass M-type stars. We have spatially resolved a debris disk around the

Herschel discovery of a new class of cold, faint debris discs

We present Herschel PACS 100 and 160 μm observations of the solar-type stars α Men, HD 88230 and HD 210277, which form part of the FGK stars sample of the Herschel open time key programme (OTKP)

Planet formation in the habitable zone of α Centauri B

Recent studies have shown that α Centauri B might be, from an observational point of view, an ideal candidate for the detection of an Earth-like planet in or near its habitable zone (0.5-0.9au). We