Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

A compact multi-planet system around a bright nearby star from the Dispersed Matter Planet Project


An Author Correction to this article was published on 13 March 2020

This article has been updated


To put the Solar System’s terrestrial planets in context, the detection and characterization of low-mass exoplanets is important but challenging. The Dispersed Matter Planet Project targets stars with anomalously low Ca ii H and K chromospheric emission, indicative of circumstellar absorbing gas. Here we report high-precision, high-cadence radial-velocity measurements of the F8V star DMPP-1 (HD 38677). These were motivated by depressed Ca ii H and K line cores indicative of short-period, ablating planets producing circumstellar gas. We find a compact planetary system with orbital periods of about 2.9–19 days, comprising three super-Earth-mass planets (about 3–10 M) and one Neptune-mass planet (about 24 M). The irradiated super-Earths may be remnant cores of giant planets after mass loss while crossing the Neptune desert. A priori inferences about the presence of short-period planets enabled the efficient discovery of the DMPP-1 planets. We anticipate informative follow-up characterization studies.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: RV measurements and Keplerian solutions corresponding to parameters in Table 2.
Fig. 2: Log-likelihood (ΔlogL) periodograms of the window function and the four-Keplerian search for the complete dataset.
Fig. 3: Radial velocity modulations for each planet in our preferred solution.
Fig. 4: Log-likelihood periodograms as in Fig. 2 with inclusion of S-index activity correlation.
Fig. 5: Radial velocity modulations for each Keplerian signal in the solution incorporating an S-index correlation.
Fig. 6: Numerical simulations of the preferred four-Keplerian solution for DMPP-1 (Table 2a).

Similar content being viewed by others

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. All RV data, collected under ESO programmes 096.C-0876(A) and 098.C-0269(A), 098.C0499(A), 098.C0269(B), 099.C-0798(A) and 0100.C-0836(A), are publicly available from the ESO archive (

Change history


  1. Vidal-Madjar, A. et al. An extended upper atmosphere around the extrasolar planet HD209458b. Nature 422, 143–146 (2003).

    Article  ADS  Google Scholar 

  2. Hebb, L. et al. WASP-12b: the hottest transiting extrasolar planet yet discovered. Astrophys. J. 693, 1920–1928 (2009).

    Article  ADS  Google Scholar 

  3. Fossati, L. et al. Metals in the exosphere of the highly irradiated planet WASP-12b. Astrophys. J. 714, L222–L227 (2010).

    Article  ADS  Google Scholar 

  4. Haswell, C. A. et al. Near-ultraviolet absorption, chromospheric activity, and star-planet interactions in the WASP-12 system. Astrophys. J. 760, 79 (2012).

    Article  ADS  Google Scholar 

  5. Haswell, C. A. WASP-12b: a mass-losing extremely hot Jupiter. In Handbook of Exoplanets (eds Deeg, H. J. & Belmonte, J. A.) 97 (Springer International Publishing, 2017).

  6. Rappaport, S. et al. Possible disintegrating short-period super-Mercury orbiting KIC 12557548. Astrophys. J. 752, 1 (2012).

    Article  ADS  Google Scholar 

  7. Staab, D. Enshrouded Exoplanetary Systems. PhD thesis, The Open University (2018).

  8. Fossati, L. et al. Absorbing gas around the WASP-12 planetary system. Astrophys. J. 766, L20 (2013).

    Article  ADS  Google Scholar 

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

  10. Staab, D. et al. SALT observations of the chromospheric activity of transiting planet hosts: mass-loss and star-planet interactions. Mon. Not. R. Astron. Soc. 466, 738–748 (2017).

    Article  ADS  Google Scholar 

  11. Arriagada, P. Chromospheric activity of southern stars from the Magellan Planet Search Program. Astrophys. J. 734, 70 (2011).

    Article  ADS  Google Scholar 

  12. Minniti, D. et al. Low-mass companions for five solar-type stars from the Magellan Planet Search Program. Astrophys. J. 693, 1424–1430 (2009).

    Article  ADS  Google Scholar 

  13. Bernstein, R., Shectman, S. A., Gunnels, S. M., Mochnacki, S. & Athey, A. E. MIKE: a double echelle spectrograph for the Magellan telescopes at Las Campanas Observatory. Proc. SPIE 4841, 1694–1704 (2003).

  14. Mayor, M. et al. Setting new standards with HARPS. Messenger 114, 20–24 (2003).

    ADS  Google Scholar 

  15. 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. Supp. 200, 15 (2012).

    Article  ADS  Google Scholar 

  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).

    Article  Google Scholar 

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

    Article  ADS  Google Scholar 

  18. Tuomi, M., Jones, H. R. A., Barnes, J. R., Anglada-Escudé, G. & Jenkins, J. S. Bayesian search for low-mass planets around nearby M dwarfs—estimates for occurrence rate based on global detectability statistics. Mon. Not. R. Astron. Soc. 441, 1545–1569 (2014).

    Article  ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  20. 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).

    Article  ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  22. Dawson, R. I. Tightly packed planetary systems. In Handbook of Exoplanets (eds Deeg, H. J. & Belmonte, J. A.) (Springer International Publishing, 2017).

  23. Tremaine, S. The statistical mechanics of planet orbits. Astrophys. J. 807, 157 (2015).

    Article  ADS  Google Scholar 

  24. Moriarty, J. & Ballard, S. The Kepler dichotomy in planetary disks: linking Kepler observables to simulations of late-stage planet formation. Astrophys. J. 832, 34 (2016).

    Article  ADS  Google Scholar 

  25. Dawson, R. I. Time domain challenges for exoplanets. Am. Astron. Soc. 227, 310.03 (2016).

    ADS  Google Scholar 

  26. Agol, E. & Fabrycky, D. C. Transit-timing and duration variations for the discovery and characterization of exoplanets. In Handbook of Exoplanets (eds Deeg, H. J. & Belmonte, J. A.) (Springer International Publishing, 2017).

  27. Sigurdsson, H. et al. (eds) The Encyclopedia of Volcanoes 2nd edn (Elsevier Science & Technology, 2015).

  28. 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).

    Article  ADS  Google Scholar 

  29. 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).

    Article  ADS  Google Scholar 

  30. Fossati, L. et al. The effect of ISM absorption on stellar activity measurements and its relevance for exoplanet studies. Astron. Astrophys. 601, A104 (2017).

    Article  Google Scholar 

  31. Soto, M. G. & Jenkins, J. S. Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars 715 (SPECIES). I. Code description and dwarf stars catalogue. Mon. Not. R. Astron. Soc. 615, A76 (2018).

    Google Scholar 

  32. Sneden, C., Bean, J., Ivans, I., Lucatello, S. & Sobeck, J. MOOG: LTE line analysis and spectrum synthesis. Astrophys. Source Code Library 1202.009 (2012).

  33. Castelli, F. & Kurucz, R. L. New grids of ATLAS9 model atmospheres. Preprint at (2004)

  34. Morton, T. D. isochrones: stellar model grid package. Astrophys. Source Code Library 1503.010 (2015).

  35. Dotter, A. MESA Isochrones and Stellar Tracks (MIST) 0: methods for the construction of stellar isochrones. Astrophys. J. 222, 8 (2016).

    Article  ADS  Google Scholar 

  36. Pepe, F. et al. The HARPS search for Earth-like planets in the habitable zone. I. Very low-mass planets around HD 20794, HD 85512, and HD 192310. Astron. Astrophys. 534, A58 (2011).

    Article  Google Scholar 

  37. Gilliland, R. L. et al. Kepler-68: three planets, one with a density between that of Earth and ice giants. Astrophys. J. 766, 40 (2013).

    Article  ADS  Google Scholar 

  38. Jackson, B., Greenberg, R. & Barnes, R. Tidal evolution of close-in extrasolar planets. Astrophys. J. 678, 1396–1406 (2008).

    Article  ADS  Google Scholar 

  39. Baluev, R. V. Accounting for velocity jitter in planet search surveys. Mon. Not. R. Astron. Soc. 393, 969–978 (2009).

    Article  ADS  Google Scholar 

  40. Baluev, R. V. Assessing the statistical significance of periodogram peaks. Mon. Not. R. Astron. Soc. 385, 1279–1285 (2008).

    Article  ADS  Google Scholar 

  41. Butler, R. P. et al. The LCESr HIRES/Keck Precision Radial Velocity Exoplanet Survey. Astron. J. 153, 208 (2017).

    Article  ADS  Google Scholar 

  42. Gillon, M. et al. Two massive rocky planets transiting a K-dwarf 6.5 parsecs away. Nat. Astron. 1, 0056 (2017).

    Article  ADS  Google Scholar 

Download references


This work is based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 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 were based on observations awarded by ESO using HARPS. This research has made use of the SIMBAD data base, operated at CDS, Strasbourg, France.

Author information

Authors and Affiliations



D.S. performed target selection, and contributed to writing of proposals, making figures, initial RV analyses and technical details of the paper. C.A.H. plans and leads all aspects of the DMPP collaboration, secured the funding, and wrote the proposals and much of the paper. J.R.B. contributed to proposals, performed final RV analyses, wrote the initial paper draft and the technical sections and made the figures. G.A.-E. provided software and expertise. L.F. contributed to the analysis and proposal writing. J.S.J. and M.G.S. provided expertise on stellar activity, the log RHK metric and contributed stellar parameter analyses. 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.

Corresponding author

Correspondence to C. A. Haswell.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Astronomy thanks Teruyuki Hirano for their contribution to the peer review of this work.

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

Supplementary information

Supplementary Information

Supplementary text, Supplementary Table 1, Supplementary references, Supplementary Figs. 1–4.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Staab, D., Haswell, C.A., Barnes, J.R. et al. A compact multi-planet system around a bright nearby star from the Dispersed Matter Planet Project. Nat Astron 4, 399–407 (2020).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing