CARMENES project boosts the number of known planets in the solar neighbourhood
The study, led by a consortium of Spanish and German institutions, has the prominent participation of IEEC researchers
The instrument has proven to be a success and will continue to provide information on small cool stars until at least the end of 2023
The CARMENES project has just published data from about 20,000 observations taken between 2016 and 2020 for a sample of 362 nearby cool stars. The project, financed by Spanish and German funds, uses an instrument at Calar Alto Observatory (Spain) with the purpose of finding Earth-like exoplanets (rocky and temperate), with the possibility of harbouring water on their surface if they are located in the so-called "habitable zone" of their star. Notable among the multitude of released data measurements are those that have led to the discovery of 59 exoplanets, a dozen of which are potentially habitable. The study has been published today in the journal Astronomy & Astrophysics.
CARMENES is the name of the scientific project, but also of the instrument used to make the observations and of the consortium that designed and built it. More than 200 scientists and engineers from 11 Spanish and German institutions are involved in the project, in which researchers from the Institute of Space Studies of Catalonia (IEEC — Institut d’Estudis Espacials de Catalunya) at the Institute of Space Sciences (ICE-CSIC) have a prominent role. In fact, the Director of the IEEC, Ignasi Ribas, is the first author of this recently published work. He is accompanied by about a hundred experts from more than 30 research centres, including the other institutions of the consortium: the Max-Planck-Institut für Astronomie (MPIA), the Instituto de Astrofísica de Andalucía (IAA-CSIC), the Landessternwarte Königstuhl (LSW), the Institut für Astrophysik Göttingen (IAG), the Universidad Complutense de Madrid (UCM), the Thüringer Landessternwarte Tautenburg (TLS), the Instituto de Astrofísica de Canarias (IAC), the Hamburger Sternwarte (HS), the Centro de Astrobiología (CAB, CSIC-INTA) and the Centro Astronómico Hispano-Alemán (CAHA).
The CARMENES instrument is an optical and near-infrared spectrograph, i.e. a device that measures both visible and infrared light from the objects it is pointing at. It was installed in 2015 at Calar Alto Observatory with the aim of finding terrestrial-type exoplanets in nearby cool stars (the so-called red dwarfs). The light collected from a given star (the stellar spectrum) can give away the presence of exoplanets, as it allows to measure the small motions of the star produced by the gravitational pull of the planets orbiting it.
The high-resolution spectra obtained with CARMENES are used to determine the velocity of the star with an accuracy of one metre per second, which is a major technological challenge. This makes it possible to find small planets around low-mass stars.
Caption: Recreation of an Earth-size planet in the habitable zone of a nearby red dwarf.
Credits: Render Area / CARMENES/ J. A. Caballero
"Since it came into operation, CARMENES has re-analysed 17 known planets and has discovered and confirmed 59 new planets in the vicinity of our Solar System, making a significant contribution to expanding the census of nearby exoplanets," explains Dr Ribas. In fact, this instrument has boosted the number of exoplanets we know about around nearby cool stars by doubling those detected with the previously described method. It is to be hoped that, with the publication of this first large dataset, the research community will analyse it and will be able to further increase its scientific output. Importantly, CARMENES has observed almost half of all nearby small stars (a part of them can only be observed from the southern hemisphere). In addition, the spectra obtained also provide extremely valuable information about the atmospheres of the stars and their planets, among other features.
The paper published in Astronomy & Astrophysics is the 100th article of the CARMENES consortium, which shows how successful the project has been in providing information about Earth-like exoplanets and their stars. In this study, the visible-light data have been released. Experts are still improving the processing of the infrared data, so when they are published, astronomers will have a second large set of observations to work with.
The CARMENES project continues in CARMENES Legacy-Plus, which started in 2021 and keeps taking more observations of the same stars. “In order to determine the existence of planets around a star, we observe it a minimum of 50 times,” explains Juan Carlos Morales, IEEC researcher at ICE-CSIC. He adds: “Although the first round of data has already been published so that the scientific community can access them, the observations are still ongoing.” The observations made in this project extension will continue at least until the end of 2023.
Press release prepared in collaboration with the Communication Offices of the Institute of Space Sciences (ICE-CSIC), the Centro de Astrobiología (CAB, CSIC-INTA), the Instituto de Astrofísica de Andalucía (IAA-CSIC), the Instituto de Astrofísica de Canarias (IAC) and the Universidad Complutense de Madrid (UCM).
Caption: All planets discovered with the same method as CARMENES, but with other instruments, are shown as grey dots in the image. With the data collected in the period 2016-2020, CARMENES has discovered and confirmed 6 "Jupiter-like" planets (with masses more than 50 times that of the Earth), 10 "Neptunes" (10 to 50 Earth masses) and 43 Earths and super-Earths (up to 10 Earth masses). The vertical axis shows what star type the planets orbit around, from the coolest and smallest red dwarfs to brighter and hotter stars (the Sun would correspond to the second from the top). The horizontal axis gives an idea of the distance from the planet to the star by showing the time it takes to complete the orbit. Planets that are in the habitable zone (blue-shaded area) can harbour liquid water on their surface.
Credit: Institute of Space Studies of Catalonia (IEEC)
Links
– CARMENES
– Calar Alto Observatory
– IEEC
– ICE-CSIC
More information
This research is presented in a paper entitled “The CARMENES search for exoplanets around M dwarfs. Guaranteed Time Observations Data Release 1 (2016-2020)”, by I. Ribas, A. Reiners et al., to appear in the journal Astronomy & Astrophysics on 22 February 2023.
The Institute of Space Studies of Catalonia (IEEC — Institut d’Estudis Espacials de Catalunya) promotes and coordinates space research and technology development in Catalonia for the benefit of society. IEEC fosters collaborations both locally and worldwide and is an efficient agent of knowledge, innovation and technology transfer. As a result of 25 years of high-quality research, done in collaboration with major international organisations, IEEC ranks among the best international research centers, focusing on areas such as: astrophysics, cosmology, planetary science, and Earth Observation. IEEC’s engineering division develops instrumentation for ground- and space-based projects, and has extensive experience in working with private or public organisations from the aerospace and other innovation sectors.
IEEC is a private non-profit foundation, governed by a Board of Trustees composed of Generalitat de Catalunya and four other institutions that each have a research unit, which together constitute the core of IEEC R&D activity: the Universitat de Barcelona (UB) with the research unit ICCUB — Institute of Cosmos Sciences; the Universitat Autònoma de Barcelona (UAB) with the research unit CERES — Center of Space Studies and Research; the Universitat Politècnica de Catalunya · BarcelonaTech (UPC) with the research unit CTE — Research Group in Space Sciences and Technologies; the Spanish Research Council (CSIC) with the research unit ICE — Institute of Space Sciences. The IEEC is a CERCA (Centres de Recerca de Catalunya) centre.
Contacts
IEEC Communication Office
Barcelona, Spain
E-mail: comunicacio@ieec.cat
Lead Researcher at IEEC
Barcelona, Spain
Ignasi Ribas
Institute of Space Studies of Catalonia (IEEC)
Institute of Space Sciences (ICE-CSIC)
E-mail: iribas@ieec.cat