An ablating 2.6 M planet in an eccentric binary from the Dispersed Matter Planet Project



Earth-mass exoplanets are difficult to detect. The Dispersed Matter Planet Project (DMPP) identifies stars that are likely to host the most detectable low-mass exoplanets. The star DMPP-3 (HD 42936) shows signs of circumstellar absorption, indicative of mass loss from ablating planets. Here, we report the radial velocity discovery of a highly eccentric 507 d binary companion and a hot super-Earth-mass planet in a 6.67 d orbit around the primary star. DMPP-3A is a solar-type star while DMPP-3B is just massive enough to fuse hydrogen. The binary, with semi-major axis 1.22 ± 0.02 au, is considerably tighter than others known to host planets orbiting only one of the component stars. The configuration of the DMPP-3 planetary system is rare and indicates dynamical interactions, though the evolutionary history is not entirely clear. DMPP-3A b is possibly the residual core of a giant planet precursor, consistent with the inferred circumstellar gas shroud.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1: Observed and fitted RVs for DMPP-3.
Fig. 2: Periodogram searches for variability in the DMPP-3 RV data.
Fig. 3: log likelihood periodograms (red lines) of the activity indicators S-index, FWHM and BIS.
Fig. 4: Activity indices versus RVs (both plotted with 1σ uncertainties).

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. Raw and processed spectra can be obtained from the European Southern Observatory’s data archive at

Code availability

The SPECIES code13 is publicly available at and the EMPEROR code at


  1. 1.

    Günther, M. N. et al. Unmasking the hidden NGTS-3Ab: a hot Jupiter in an unresolved binary system. Mon. Not. R. Astron. Soc. 478, 4720–4737 (2018).

  2. 2.

    Schwarz, R., Funk, B., Zechner, R. & Bazsó, Á. New prospects for observing and cataloguing exoplanets in well-detached binaries. Mon. Not. R. Astron. Soc. 460, 3598–3609 (2016).

  3. 3.

    Anglada-Escudé, G. et al. A terrestrial planet candidate in a temperate orbit around Proxima Centauri. Nature 536, 437–440 (2016).

  4. 4.

    Hsu, D. C., Ford, E. B., Raggozine, D. & Morehead, R. C. Improving the accuracy of planet occurrence rates from Kepler using approximate Bayesian computation. Astron. J. 155, 205–226 (2018).

  5. 5.

    Kraus, A. L., Ireland, M. J., Huber, D., Mann, A. W. & Dupuy, T. J. The impact of stellar multiplicity on planetary systems. I. The ruinous influence of close binary companions. Astron. J. 152, 8–24 (2016).

  6. 6.

    Gong, Y.-X. & Ji, J. Formation of S-type planets in close binaries: scattering-induced tidal capture of circumbinary planets. Mon. Not. R. Astron. Soc. 478, 4565–4574 (2018).

  7. 7.

    Haswell, C. A. et al. Dispersed Matter Planet Project discoveries of ablating planets orbiting nearby bright stars. Nat. Astron. (2019).

  8. 8.

    Schrijver, C. J. Magnetic structure in cool stars. XI. Relations between radiative fluxes measuring stellar activity, and evidence for two components in stellar chromospheres. Astron. Astrophys. 172, 111–123 (1987).

  9. 9.

    Houk, N. & Cowley, A. P. Catalogue of Two Dimensional Spectral Types for the HD Stars Vol. 1 (Department of Astronomy, University of Michigan, 1975).

  10. 10.

    Gaia Collaboration Gaia data release 1. Summary of the astrometric, photometric, and survey properties. Astron. Astrophys. 595, A2 (2016).

  11. 11.

    Jenkins, J. S. et al. Metallicities and activities of southern stars. Astron. Astrophys. 485, 571–584 (2008).

  12. 12.

    Jenkins, J. S. et al. Chromospheric activities and kinematics for solar type dwarfs and subgiants: analysis of the activity distribution and the AVR. Astron. Astrophys. 531, A8 (2011).

  13. 13.

    Soto, M. G. & Jenkins, J. S. Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue. Mon. Not. R. Astron. Soc. 615, A76 (2018).

  14. 14.

    Jenkins, J. S. et al. First results from the Calan–Hertfordshire Extrasolar Planet Search: exoplanets and the discovery of an eccentric brown dwarf in the desert. Mon. Not. R. Astron. Soc. 398, 911–917 (2009).

  15. 15.

    Zechmeister, M. & Kurster, M. The generalised Lomb–Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms. Astron. Astrophys. 496, 577–584 (2009).

  16. 16.

    Anglada-Escudé, G. et al. A dynamically-packed planetary system around GJ 667C with three super-Earths in its habitable zone. Astron. Astrophys. 556, A126 (2013).

  17. 17.

    Burke, E. W. Jr, Rolland, W. W. & Boy, W. R. A photoelectric study of magnetic variable stars. J. R. Astron. Soc. Can. 64, 353–369 (1970).

  18. 18.

    Dworetsky, M. M. A period-finding method for sparse randomly spaced observations of ‘How long is a piece of string?’. Mon. Not. R. Astron. Soc. 203, 917–924 (1983).

  19. 19.

    Meschiari, S. et al. Systemic: a testbed for characterizing the detection of extrasolar planets. I. The Systemic Console package. Publ. Astron. Soc. Pac. 121, 1016–1027 (2009).

  20. 20.

    Fulton, B. J., Petigura, E. A., Blunt, S. & Sinukoff, E. RadVel: the radial velocity modeling toolkit. Publ. Astron. Soc. Pac. 130, 044504 (2018).

  21. 21.

    Vaughan, A. H., Preston, G. W. & Wilson, O. C. Flux measurements of Ca II and K emission. Publ. Astron. Soc. Pac. 90, 267–274 (1978).

  22. 22.

    Meunier, N., Desort, M. & Lagrange, A.-M. Using the Sun to estimate Earth-like planets detection capabilities. II. Impact of plages. Astron. Astrophys. 512, A39 (2010).

  23. 23.

    Meunier, N. et al. Variability of stellar granulation and convective blueshift with spectral type and magnetic activity. I. K and G main sequence stars. Astron. Astrophys. 597, A52 (2017).

  24. 24.

    Burrows, A. et al. A nongray theory of extrasolar giant planets and brown dwarfs. Astrophys. J. 491, 856–875 (1997).

  25. 25.

    Chabrier, G. & Baraffe, I. Theory of low-mass stars and substellar objects. Annu. Rev. Astron. Astrophys. 38, 337–377 (2000).

  26. 26.

    Dieterich, S. B. et al. The solar neighborhood. XXXII. The hydrogen burning limit. Astron. J. 147, L94 (2014).

  27. 27.

    Kiman, R. et al. Exploring the age-dependent properties of M and L dwarfs using Gaia and SDSS. Astron. J. 157, 231 (2019).

  28. 28.

    Gomes, J. I. et al. Two new ultracool benchmark systems from WISE+2MASS. Mon. Not. R. Astron. Soc. 431, 2745–2755 (2013).

  29. 29.

    Baron, F. et al. Discovery and characterization of wide binary systems with a very low mass component. Astrophys. J. 802, 37 (2015).

  30. 30.

    Gálvez-Ortiz, M. C., Solano, E., Lodieu, N. & Aberasturi, M. Discovery of wide low and very low mass binary systems using virtual observatory tools. Mon. Not. R. Astron. Soc. 466, 2983–3006 (2017).

  31. 31.

    dos Santos, L. A. et al. Spectroscopic binaries in the Solar Twin Planet Search program: from substellar-mass to M dwarf companions. Mon. Not. R. Astron. Soc. 472, 3425–3436 (2017).

  32. 32.

    Tang, S.-Y. et al. Characterization of stellar and substellar members in the Coma Berenices star cluster. Astrophys. J. 862, 106 (2018).

  33. 33.

    Zapatero Osorio, M. R. et al. Trigonometric parallaxes of young field L dwarfs. Astron. Astrophys. 568, A6 (2014).

  34. 34.

    von Boetticher, A. et al. The EBLM project. III. A Saturn-size low-mass star at the hydrogen-burning limit. Astron. Astrophys. 604, L6 (2017).

  35. 35.

    Cañas, C. I. et al. Kepler-503b: an object at the hydrogen burning mass limit orbiting a subgiant star. Astrophys. J. 861, L4 (2018).

  36. 36.

    Ogilvie, G. I. & Lin, D. N. C. Tidal dissipation in rotating solar-type stars. Astrophys. J. 661, 1180–1191 (2007).

  37. 37.

    Baraffe, I., Homeier, D., Allard, F. & Chabrier, G. New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit. Astron. Astrophys. 577, A42 (2015).

  38. 38.

    Lovis, C. et al. Atmospheric characterization of Proxima b by coupling the SPHERE high-contrast imager to the ESPRESSO spectrograph. Astron. Astrophys. 599, A16 (2017).

  39. 39.

    Barnes, J. R. et al. A search for molecules in the atmosphere of HD 189733b. Mon. Not. R. Astron. Soc. 401, 445–454 (2010).

  40. 40.

    Wilson, P. A. et al. The SOPHIE search for northern extrasolar planets. IX. Populating the brown dwarf desert. Astron. Astrophys. 588, A144 (2016).

  41. 41.

    Haswell, C. A. Transiting Exoplanets (Cambridge University Press, 2010)

  42. 42.

    Holman, M. J. & Wiegert, P. A. Long-term stability of planets in binary systems. Astron. J. 117, 621–628 (1999).

  43. 43.

    Santerne, A. et al. SOPHIE velocimetry of Kepler transit candidates. XII. KOI-1257 b: a highly eccentric three-month period transiting exoplanet. Astron. Astrophys. 571, A37 (2014).

  44. 44.

    Masuda, K. Eccentric companions to Kepler-448b and Kepler-693b: clues to the formation of warm Jupiters. Astron. J. 154, 64 (2017).

  45. 45.

    Ortiz, M. et al. Precise radial velocities of giant stars IX. HD 59686 Ab: a massive circumstellar planet orbiting a giant star in a 13.6 au eccentric binary system. Astron. Astrophys. 595, A55 (2016).

  46. 46.

    Ramm, D. J. et al. The conjectured S-type retrograde planet in ν Octantis: more evidence including four years of iodine-cell radial velocities. Mon. Not. R. Astron. Soc. 460, 3706–3719 (2016).

  47. 47.

    Naoz, S. The eccentric Kozai–Lidov effect and its applications. Annu. Rev. Astron. Astrophys. 54, 441–489 (2016).

  48. 48.

    Antognini, J. M. O. Timescales of Kozai–Lidov oscillations at quadrupole and octupole order in the test particle limit. Mon. Not. R. Astron. Soc. 452, 3610–3619 (2015).

  49. 49.

    Guszejnov, D., Hopkins, P. F., Grudić, M. Y., Krumholz, M. R. & Federrath, C. Isothermal fragmentation: is there a low-mass cut-off? Mon. Not. R. Astron. Soc. 480, 182–191 (2018).

  50. 50.

    Mazeh, T., Holczer, T. & Faigler, S. Dearth of short-period Neptunian exoplanets: a desert in period-mass and period-radius planes. Astron. Astrophys. 589, A75 (2016).

  51. 51.

    Van Eylen, V. et al. An asteroseismic view of the radius valley: stripped cores, not born rocky. Mon. Not. R. Astron. Soc. 479, 4786–4795 (2018).

  52. 52.

    Vidotto, A. A. et al. Characterization of the HD 219134 multi-planet system II. Stellar-wind sputtered exospheres in rocky planets b & c. Mon. Not. R. Astron. Soc. 481, 5296–5306 (2018).

  53. 53.

    Staab, D. et al. A compact multi-planet system around a bright nearby star from the Dispersed Matter Planet Project. Nat. Astron. (2019).

  54. 54.

    Anglada-Escudé, G. & Butler, R. P. The HARPS-TERRA Project. I. Description of the algorithms, performance, and new measurements on a few remarkable stars observed by HARPS. Astrophys. J. Suppl. Ser. 200, 15 (2012).

  55. 55.

    Lomb, N. R. Least-squares frequency analysis of unequally spaced data. Physics 39, 447–462 (1976).

  56. 56.

    Scargle, J. D. Studies in astronomical time series analysis. II. Statistical aspects of spectral analysis of unevenly spaced data. Astrophys. J. 263, 835–853 (1982).

  57. 57.

    Dawson, R. I. & Fabrycky, D. C. Radial velocity planets de-aliased: a new short period for super-Earth 55 Cnc e. Astrophys. J. 722, 937–953 (2010).

  58. 58.

    Lo Curto, G. et al. HARPS gets new fibres after 12 years of operations. Messenger 162, 9–15 (2015).

  59. 59.

    Rein, H. & Liu, S.-F. REBOUND: an open-source multi-purpose N-body code for collisional dynamics. Astron. Astrophys. 537, A128 (2012).

  60. 60.

    Rein, H. & Spiegel, D. S. IAS15: a fast, adaptive, high-order integrator for gravitational dynamics, accurate to machine precision over a billion orbits. Mon. Not. R. Astron. Soc. 446, 1424–1437 (2015).

Download references


This work is based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 081.C-0148(A), 088.C-0662(A) and 091.C-0866(C), 096.C-0876(A) and 098.C-0269(A), 098.C0499(A), 098.C0269(B), 099.C-0798(A) and 0100.C-0836(A). D.S. was supported by an STFC studentship. C.A.H. and J.R.B. were supported by STFC Consolidated Grants ST/L000776/1 and ST/P000584/1. G.A.-E. was supported by STFC Consolidated Grant ST/P000592/1. J.S.J. acknowledges support by FONDECYT grant 1161218 and partial support from CONICYT project Basal AFB-170002. M.R.D. acknowledges the support of CONICYT-PFCHA/Doctorado Nacional-21140646, Chile and project Basal AFB-170002. These results are based on observations awarded by ESO, using HARPS. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France.

Author information

J.R.B. contributed to proposals, performed RV analyses and wrote the paper. C.A.H. led all aspects of the DMPP collaboration, secured the funding, wrote the proposals and co-wrote the paper. D.S. performed target selection, contributed to writing of proposals, initial RV analyses and technical details of the paper. G.A.-E. provided software and expertise. L.F. contributed to the analysis and proposal writing. J.S.J., M.G.S. and P.A.P.R. provided expertise on stellar activity, the log HK metric, contributed stellar parameter analyses and performed RV solution checks. D.S., C.A.H., J.R.B., J.P.J.D., J.C. and M.R.D. performed observations with HARPS. All authors were given the opportunity to review the results and comment on the manuscript.

Correspondence to John R. Barnes.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary text and Table 1.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Barnes, J.R., Haswell, C.A., Staab, D. et al. An ablating 2.6 M planet in an eccentric binary from the Dispersed Matter Planet Project. Nat Astron (2019).

Download citation

Further reading