2013/05/31 by Diana Dragomir, Jaymie M. Matthews, Jason D. Eastman +9 · 5 citations
Physics and Astronomy · Social Sciences · #Astronomy and Astrophysical Research #Educational Leadership and Practices #Ephemeris #Exoplanet #Measure (data warehouse) #Planet #RADIUS #Radial velocity #Star (game theory) #Stellar, planetary, and galactic studies #Transit (satellite) #Transit time #astro-ph.EP
paper · pdf · doi:10.1088/2041-8205/772/1/l2
20 pages, 4 figure, 2 tables, published version; appeared in ApJ Letters, volume 772
openalex publication_date 2013/07/01 · arxiv created 2013/11/10 · arxiv updated 2015/06/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Through photometric monitoring of the extended transit window of HD 97658b with the MOST space telescope, we have found that this exoplanet transits with an ephemeris consistent with that predicted from radial velocity measurements. The mid-transit times are 5.6σ earlier than those of the unverified transit-like signals reported in 2011, and we find no connection between the two sets of events. The transit depth together with our determined stellar radius ( ) indicates a 2.34 R ⊕ super-Earth. When combined with the radial velocity determined mass of 7.86 ± 0.73 M ⊕ , our radius measure allows us to derive a planet density of 3.44 g cm −3 . Models suggest that a planet with our measured density has a rocky core that is enveloped in an atmosphere composed of lighter elements. The star of the HD 97658 system is the second brightest known to host a transiting super-Earth, facilitating follow-up studies of this not easily daunted, warm and likely volatile-rich exoplanet.