Tidal Venuses: Triggering a Climate Catastrophe via Tidal Heating
... librium state where they rotate faster than synchronous with an “equilibrium” or “pseudosynchronous” period. This aspect of tidal theory has been known for decades (e.g. Goldreich, 1966; Greenberg and Weidenschilling, 1984), but has only recently been pointed out for the case of exoplanets (Barnes ...
... librium state where they rotate faster than synchronous with an “equilibrium” or “pseudosynchronous” period. This aspect of tidal theory has been known for decades (e.g. Goldreich, 1966; Greenberg and Weidenschilling, 1984), but has only recently been pointed out for the case of exoplanets (Barnes ...
MEarth
... Earth-sized planets orbiting M dwarfs. This possibility is brought about by the small surface areas and temperatures of M dwarfs, which lead to significantly more favorable planet-star contrast ratios. This ratio for a habitable 2 R⊕ planet orbiting an M5 is 0.05% (in the Rayleigh-Jeans limit), le ...
... Earth-sized planets orbiting M dwarfs. This possibility is brought about by the small surface areas and temperatures of M dwarfs, which lead to significantly more favorable planet-star contrast ratios. This ratio for a habitable 2 R⊕ planet orbiting an M5 is 0.05% (in the Rayleigh-Jeans limit), le ...
Effect of the stellar spin history on the tidal evolution of close
... use a dissipation factor of σ∗,dM = 2.006 ×10−60 g−1 cm−2 s−1 for the 0.1 M stars in our calculations (Hansen 2010). No scaling of the M-dwarf dissipation factor has been performed compared to the brown dwarf value. In this work, we varied the stellar dissipation factor by a few orders of magnitude ...
... use a dissipation factor of σ∗,dM = 2.006 ×10−60 g−1 cm−2 s−1 for the 0.1 M stars in our calculations (Hansen 2010). No scaling of the M-dwarf dissipation factor has been performed compared to the brown dwarf value. In this work, we varied the stellar dissipation factor by a few orders of magnitude ...
The Astrophysics of Planetary Habitability
... 2.4. Stellar Activity Evolution and the Atmospheres of Terrestrial Planets 33 2.5. An age-period-activity relation for M dwarfs: implications for planetary habitability . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 2.6. The effects of M dwarf magnetic fields and winds on potentially habit ...
... 2.4. Stellar Activity Evolution and the Atmospheres of Terrestrial Planets 33 2.5. An age-period-activity relation for M dwarfs: implications for planetary habitability . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 2.6. The effects of M dwarf magnetic fields and winds on potentially habit ...
Disentangling degenerate solutions from primary transit and
... transit measurements of HD 189733b at near-IR wavelengths displayed features indicative of the presence of water, consistent with its expected large abundance and dominant role in the spectra of hot Jupiter exoplanets [3,4]. Thermal emission was first detected from measurements of HD 209458b’s passag ...
... transit measurements of HD 189733b at near-IR wavelengths displayed features indicative of the presence of water, consistent with its expected large abundance and dominant role in the spectra of hot Jupiter exoplanets [3,4]. Thermal emission was first detected from measurements of HD 209458b’s passag ...
Extrasolar Planets: An Amateur`s Search
... Utilizing each of the four identified planet forming factors of stars, this study completed a series of descriptive statistical distributions designed to summarize the number of stars exhibiting each of the factors. The fifth factor, multiplicity of a star system, is described in quantitative terms ...
... Utilizing each of the four identified planet forming factors of stars, this study completed a series of descriptive statistical distributions designed to summarize the number of stars exhibiting each of the factors. The fifth factor, multiplicity of a star system, is described in quantitative terms ...
UK Exoplanet community meeting 2017
... perspective of exo-planetary systems, whilst at the same time deepening our knowledge of Earth’s formation. Profound questions still remain as to the origin of Earth’s atmosphere, continents, and habitable climate, questions which are ultimately stymied by having only one natural laboratory in which ...
... perspective of exo-planetary systems, whilst at the same time deepening our knowledge of Earth’s formation. Profound questions still remain as to the origin of Earth’s atmosphere, continents, and habitable climate, questions which are ultimately stymied by having only one natural laboratory in which ...
Phase light curves for extrasolar Jupiter and Saturn
... is high enough and yet the total reflected light still measurable. Since direct imaging will yield both the orbit and the luminosity of the planet simultaneously, it will be a robust detection method that will add greatly to our knowledge of planetary structure and evolution; unfortunately, it is lik ...
... is high enough and yet the total reflected light still measurable. Since direct imaging will yield both the orbit and the luminosity of the planet simultaneously, it will be a robust detection method that will add greatly to our knowledge of planetary structure and evolution; unfortunately, it is lik ...
Full Programme and Abstracts - UK Exoplanet community meeting
... perspective of exo-planetary systems, whilst at the same time deepening our knowledge of Earth’s formation. Profound questions still remain as to the origin of Earth’s atmosphere, continents, and habitable climate, questions which are ultimately stymied by having only one natural laboratory in which ...
... perspective of exo-planetary systems, whilst at the same time deepening our knowledge of Earth’s formation. Profound questions still remain as to the origin of Earth’s atmosphere, continents, and habitable climate, questions which are ultimately stymied by having only one natural laboratory in which ...
Characterization of the four new transiting planets KOI
... candidates. We mainly focus on the brightest stars (Kepler magnitude K p < 14.7) harboring close-in giant planet candidates. This has allowed us to identify and characterize several new transiting planets (Santerne et al. 2011a,b; Bonomo et al. 2012; Deleuil et al. 2014), as well as more massive com ...
... candidates. We mainly focus on the brightest stars (Kepler magnitude K p < 14.7) harboring close-in giant planet candidates. This has allowed us to identify and characterize several new transiting planets (Santerne et al. 2011a,b; Bonomo et al. 2012; Deleuil et al. 2014), as well as more massive com ...
UK Exoplanet community meeting 2017
... perspective of exo-planetary systems, whilst at the same time deepening our knowledge of Earth’s formation. Profound questions still remain as to the origin of Earth’s atmosphere, continents, and habitable climate, questions which are ultimately stymied by having only one natural laboratory in which ...
... perspective of exo-planetary systems, whilst at the same time deepening our knowledge of Earth’s formation. Profound questions still remain as to the origin of Earth’s atmosphere, continents, and habitable climate, questions which are ultimately stymied by having only one natural laboratory in which ...
Radial Velocity - Yale Exoplanet
... interesting to consider here planet searches around lowerP 28.4329 m s−1 m2 sin i m1 +m2 ...
... interesting to consider here planet searches around lowerP 28.4329 m s−1 m2 sin i m1 +m2 ...
The High Eccentricity of the Planet Around 16 Cyg B
... of the tertiary exerted on the two inner bodies is different from the attraction exerted on a body at the center of mass of the inner binary system. The difference, sometimes referred to as the tidal force of the third star, can induce long-term slow modulation of the inner binary eccentricity. We w ...
... of the tertiary exerted on the two inner bodies is different from the attraction exerted on a body at the center of mass of the inner binary system. The difference, sometimes referred to as the tidal force of the third star, can induce long-term slow modulation of the inner binary eccentricity. We w ...
Planet Hunters: The First Two Planet Candidates Identified by the
... for evolved stars to show emission unless the stars are rapidly rotating or members of close spectroscopic binary systems (Isaacson & Fischer 2010; Gizis et al. 2002; Gunn et al. 1998; Gray & Nagar 1985), and we see no evidence for either of these attributes in KIC 10905746. The combination of emiss ...
... for evolved stars to show emission unless the stars are rapidly rotating or members of close spectroscopic binary systems (Isaacson & Fischer 2010; Gizis et al. 2002; Gunn et al. 1998; Gray & Nagar 1985), and we see no evidence for either of these attributes in KIC 10905746. The combination of emiss ...
Kepler-423b: a half-Jupiter mass planet transiting a very old solar
... We report the spectroscopic confirmation of the Kepler object of interest KOI-183.01 (Kepler-423b), a half-Jupiter mass planet transiting an old solar-like star every 2.7 days. Our analysis is the first to combine the full Kepler photometry (quarters 1−17) with high-precision radial velocity measure ...
... We report the spectroscopic confirmation of the Kepler object of interest KOI-183.01 (Kepler-423b), a half-Jupiter mass planet transiting an old solar-like star every 2.7 days. Our analysis is the first to combine the full Kepler photometry (quarters 1−17) with high-precision radial velocity measure ...
Event Booklet - Exoplanets I Conference
... uses the Kepler spacecraft to observe different fields along the ecliptic in ~80 day campaigns. Over K2’s lifetime (~18 campaigns or ~4 years), K2 will discover a significant number of transiting exoplanets, extending the legacy of the Kepler mission. Indeed, K2 has already discovered ~50 exoplanets ...
... uses the Kepler spacecraft to observe different fields along the ecliptic in ~80 day campaigns. Over K2’s lifetime (~18 campaigns or ~4 years), K2 will discover a significant number of transiting exoplanets, extending the legacy of the Kepler mission. Indeed, K2 has already discovered ~50 exoplanets ...
Changes in a scientific concept: what is a planet? - Philsci
... conditions. According to this definition, the known planets in the Solar system are twelve: the nine planets actually known (Pluto retains his status as a planet), the larger asteroid Ceres, the recently discovered 2003UB313, and Pluto’s larger moon Charon (the barycentre of Pluto-Charon system is o ...
... conditions. According to this definition, the known planets in the Solar system are twelve: the nine planets actually known (Pluto retains his status as a planet), the larger asteroid Ceres, the recently discovered 2003UB313, and Pluto’s larger moon Charon (the barycentre of Pluto-Charon system is o ...
Biosignatures and Planetary Properties to be
... signs of habitability suggest equable conditions over geologic time versus, say limited periods in the distant or even recent past, except by assumption? ...
... signs of habitability suggest equable conditions over geologic time versus, say limited periods in the distant or even recent past, except by assumption? ...
Three newly discovered sub-Jupiter-mass planets: WASP
... as described in Collier Cameron et al. (2006), and the candidate selection process was performed as described in Collier Cameron et al. (2007). We perform a search for transits on each season of data from each camera separately and we perform combined searches on all WASP data available on each star ...
... as described in Collier Cameron et al. (2006), and the candidate selection process was performed as described in Collier Cameron et al. (2007). We perform a search for transits on each season of data from each camera separately and we perform combined searches on all WASP data available on each star ...
Kepler423b: a half-Jupiter mass planet transiting a very old solar
... the observation barycentric Julian dates in barycentric dynamical time (BJDTDB , see Eastman et al. 2010), the cross-correlation function (CCF) bisector spans, and the signal-to-noise (S/N) ratios per pixel at 5500 Å. The upper panel of Fig. 2 shows the FIES RVs of Kepler-423 and the Keplerian fit t ...
... the observation barycentric Julian dates in barycentric dynamical time (BJDTDB , see Eastman et al. 2010), the cross-correlation function (CCF) bisector spans, and the signal-to-noise (S/N) ratios per pixel at 5500 Å. The upper panel of Fig. 2 shows the FIES RVs of Kepler-423 and the Keplerian fit t ...
1 A Re-appraisal of the Habitability of Planets Around M Dwarf Stars
... Lucianne M. Walkowicz,23 Arthur L. Weber,1 and Richard E. Young9 Abstract Stable, hydrogen-burning, M dwarf stars comprise about 75% of all stars in the Galaxy. They are extremely long-lived and because they are much smaller in mass than the Sun (between 0.5 and 0.08 MSun), their temperature and ste ...
... Lucianne M. Walkowicz,23 Arthur L. Weber,1 and Richard E. Young9 Abstract Stable, hydrogen-burning, M dwarf stars comprise about 75% of all stars in the Galaxy. They are extremely long-lived and because they are much smaller in mass than the Sun (between 0.5 and 0.08 MSun), their temperature and ste ...
Extrasolar planets - Astronomisk Ungdom
... finished its cycle or if it has moved out of the range in which the telescope observed the star. As mentioned above a macula can disappear and reappear. However, planets do not vanish from their orbit without a trace or a caveat, except if it is a free planet passing the star, but those are rare and ...
... finished its cycle or if it has moved out of the range in which the telescope observed the star. As mentioned above a macula can disappear and reappear. However, planets do not vanish from their orbit without a trace or a caveat, except if it is a free planet passing the star, but those are rare and ...
Signatures of Planets in Protoplanetary and Debris
... extrapolating ṀP after a few 104 years, the above estimate of Lacc becomes ≈ 10−5 Lsun . This value for the planetary accretion luminosity is on the same order of magnitude as the luminosity derived by Burrows et al. (1997) for a young Jupiter-mass planet. Based on the density structure obtained fr ...
... extrapolating ṀP after a few 104 years, the above estimate of Lacc becomes ≈ 10−5 Lsun . This value for the planetary accretion luminosity is on the same order of magnitude as the luminosity derived by Burrows et al. (1997) for a young Jupiter-mass planet. Based on the density structure obtained fr ...
The Stability of Exomoons in the Habitable Zone
... In the investigation into the habitability of extrasolar objects, the main focus has long been on exoplanets, while exomoons have only been considered properly during the last few years. A reason for this is the obvious difficulty in detecting objects that do not primarily orbit a star, but rather a ...
... In the investigation into the habitability of extrasolar objects, the main focus has long been on exoplanets, while exomoons have only been considered properly during the last few years. A reason for this is the obvious difficulty in detecting objects that do not primarily orbit a star, but rather a ...
Solutions to exercises
... (d) To evaluate ΔTdur /Tdur , we need to use our expression for a for the specific values of M∗ = 1 M% and orbital period P = 1 day. Generally, it is advisable to substitute in expressions to obtain the answer algebraically, before substituting in numerical values. In this case, however, the quantity ...
... (d) To evaluate ΔTdur /Tdur , we need to use our expression for a for the specific values of M∗ = 1 M% and orbital period P = 1 day. Generally, it is advisable to substitute in expressions to obtain the answer algebraically, before substituting in numerical values. In this case, however, the quantity ...
Gliese 581
Gliese 581 (/ˈɡliːzə/) is a star of spectral type M3V (a red dwarf) about 20 light years away from Earth in the constellation Libra. Its estimated mass is about a third of that of the Sun, and it is the 89th closest known star to the Sun. Observations suggest that the star has a planetary system consisting of three known planets, designated Gliese 581 b, c, and e and a possibly confirmed planet, d, in order of discovery. Additional outer planets, which received the designations Gliese 581 f, and g have been proposed, but the evidence that led to the discovery claims has been shown to be the result of stellar activity mimicking the radial velocity variations due to orbiting planets.Gliese 581 has been the subject of a ""huge amount of attention"" in the quest to discover the first habitable extrasolar planet; first for c, and then d and g. Gliese 581 c, the first low-mass extrasolar planet found near a habitable zone, was discovered in April 2007. It has since been shown that under known terrestrial planet climate models, Gliese 581 c is likely to have a runaway greenhouse effect, and hence is probably too hot to be habitable, analogous to Venus. The proposed planets Gliese 581 d and Gliese 581 g also received attention as being located within the habitable zone, but their existence has subsequently been put into doubt by some authors.On 27 November 2012, the European Space Agency announced a debris disk, with at least ten times as many comets as the Solar System. This put constraints on possible planets beyond 0.75 AU.