University of Hertfordshire Research Archive

        JavaScript is disabled for your browser. Some features of this site may not work without it.

        Browse

        All of UHRABy Issue DateAuthorsTitlesThis CollectionBy Issue DateAuthorsTitles

        Arkivum Files

        My Downloads
        View Item 
        • UHRA Home
        • University of Hertfordshire
        • Research publications
        • View Item
        • UHRA Home
        • University of Hertfordshire
        • Research publications
        • View Item

        A candidate super-Earth planet orbiting near the snow line of Barnard's star

        View/Open
        1811.05955v2_aam_cs.pdf (PDF, 3Mb)
        Author
        Ribas, I.
        Tuomi, M.
        Reiners, A.
        Butler, R. P.
        Morales, J. C.
        Perger, M.
        Dreizler, S.
        Rodríguez-López, C.
        Hernández, J. I. González
        Rosich, A.
        Feng, F.
        Trifonov, T.
        Vogt, S. S.
        Caballero, J. A.
        Hatzes, A.
        Herrero, E.
        Jeffers, S. V.
        Lafarga, M.
        Murgas, F.
        Rodríguez, E.
        Strachan, J. B. P.
        Tal-Or, L.
        Teske, J.
        Toledo-Padrón, B.
        Zechmeister, M.
        Quirrenbach, A.
        Amado, P. J.
        Azzaro, M.
        Béjar, V. J. S.
        Barnes, J. R.
        Berdiñas, Z. M.
        Coleman, G.
        Cortés-Contreras, M.
        Crane, J.
        Engle, S. G.
        Guinan, E. F.
        Haswell, C. A.
        Henning, Th
        Holden, B.
        Jones, H. R. A.
        Kaminski, A.
        Kiraga, M.
        Kürster, M.
        López-González, M. J.
        Montes, D.
        Morin, J.
        Ofir, A.
        Pallé, E.
        Rebolo, R.
        Reffert, S.
        Schweitzer, A.
        Seifert, W.
        Shectman, S. A.
        Staab, D.
        Street, R. A.
        Mascareño, A. Suárez
        Tsapras, Y.
        Anglada-Escudé, G.
        Attention
        2299/21132
        Abstract
        Barnard’s star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard’s star is also among the least magnetically active red dwarfs known and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging, astrometry and direct imaging, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard’s star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard’s star, making it an excellent target for direct imaging and astrometric observations in the future.
        Publication date
        2018-11-15
        Published in
        Nature
        Published version
        https://doi.org/10.1038/s41586-018-0677-y
        Other links
        http://hdl.handle.net/2299/21132
        Metadata
        Show full item record
        Keep in touch

        © 2019 University of Hertfordshire

        I want to...

        • Apply for a course
        • Download a Prospectus
        • Find a job at the University
        • Make a complaint
        • Contact the Press Office

        Go to...

        • Accommodation booking
        • Your student record
        • Bayfordbury
        • KASPAR
        • UH Arts

        The small print

        • Terms of use
        • Privacy and cookies
        • Criminal Finances Act 2017
        • Modern Slavery Act 2015
        • Sitemap

        Find/Contact us

        • T: +44 (0)1707 284000
        • E: ask@herts.ac.uk
        • Where to find us
        • Parking
        • hr
        • qaa
        • stonewall
        • AMBA
        • ECU Race Charter
        • disability confident
        • AthenaSwan