Hubble space telescope time-series photometry of the planetary transit of HD 189733: No moon, no rings, starspots

F. Pont, L. Gilliland, C. Moutou, D. Charbonneau, F. Bouchy, M. Brown, M. Mayor, D. Queloz, N. Santos, S. Udry

Research output: Contribution to journalArticle

155 Citations (Scopus)

Abstract

We monitored three transits of the giant gas planet around the nearby K dwarf HD 189733 with the ACS camera on the Hubble Space Telescope. The resulting very-high accuracy lightcurve (signal-to-noise ratio near 15 000 on individual measurements, 35 000 on 10-min averages) allows a direct geometric measurement of the orbital inclination, radius ratio and scale of the system: = 85.68 0.04, = 0.1572 0.0004, = 8.92 0.09. We derive improved values for the stellar and planetary radius, = 0.755 0.011 , = 1.154 0.017 , and the transit ephemerides, = 2453931.12048 0.00002 + n2.218581 0.000002. The HST data also reveal clear evidence of the planet occulting spots on the surface of the star. At least one large spot complex > 80 000 km) is required to explain the observed flux residuals and their colour evolution. This feature is compatible in amplitude and phase with the variability observed simultaneously from the ground. No evidence for satellites or rings around HD 189733 is seen in the HST lightcurve. This allows us to exlude with a high probability the presence of Earth-sized moons and Saturn-type debris rings around this planet. The timing of the three transits sampled is stable to the level of a few seconds, excluding a massive second planet in outer 2:1 resonance.

Original languageEnglish (US)
Pages (from-to)1347-1355
Number of pages9
JournalAstronomy and Astrophysics
Volume476
Issue number3
DOIs
StatePublished - Dec 1 2007

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starspots
natural satellites
transit
Hubble Space Telescope
Moon
photometry
planets
planet
time series
rings
gas giant planets
ephemerides
radii
Saturn
debris
inclination
signal to noise ratios
cameras
time measurement
signal-to-noise ratio

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Pont, F., Gilliland, L., Moutou, C., Charbonneau, D., Bouchy, F., Brown, M., ... Udry, S. (2007). Hubble space telescope time-series photometry of the planetary transit of HD 189733: No moon, no rings, starspots. Astronomy and Astrophysics, 476(3), 1347-1355. https://doi.org/10.1051/0004-6361:20078269
Pont, F. ; Gilliland, L. ; Moutou, C. ; Charbonneau, D. ; Bouchy, F. ; Brown, M. ; Mayor, M. ; Queloz, D. ; Santos, N. ; Udry, S. / Hubble space telescope time-series photometry of the planetary transit of HD 189733 : No moon, no rings, starspots. In: Astronomy and Astrophysics. 2007 ; Vol. 476, No. 3. pp. 1347-1355.
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Pont, F, Gilliland, L, Moutou, C, Charbonneau, D, Bouchy, F, Brown, M, Mayor, M, Queloz, D, Santos, N & Udry, S 2007, 'Hubble space telescope time-series photometry of the planetary transit of HD 189733: No moon, no rings, starspots', Astronomy and Astrophysics, vol. 476, no. 3, pp. 1347-1355. https://doi.org/10.1051/0004-6361:20078269

Hubble space telescope time-series photometry of the planetary transit of HD 189733 : No moon, no rings, starspots. / Pont, F.; Gilliland, L.; Moutou, C.; Charbonneau, D.; Bouchy, F.; Brown, M.; Mayor, M.; Queloz, D.; Santos, N.; Udry, S.

In: Astronomy and Astrophysics, Vol. 476, No. 3, 01.12.2007, p. 1347-1355.

Research output: Contribution to journalArticle

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T1 - Hubble space telescope time-series photometry of the planetary transit of HD 189733

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AU - Pont, F.

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AU - Moutou, C.

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AU - Queloz, D.

AU - Santos, N.

AU - Udry, S.

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