Indications for an influence of Hot Jupiters
... level of log LX = 27.6 to 27.8 erg s−1 . In our XMM-Newton observation from 2013, it displays a background-subtracted count rate of 0.023 cps in the combined MOS detectors, corresponding to an X-ray luminosity of log LX = 27.75 erg s−1 . This is slightly lower than the typical X-ray luminosities fou ...
... level of log LX = 27.6 to 27.8 erg s−1 . In our XMM-Newton observation from 2013, it displays a background-subtracted count rate of 0.023 cps in the combined MOS detectors, corresponding to an X-ray luminosity of log LX = 27.75 erg s−1 . This is slightly lower than the typical X-ray luminosities fou ...
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 ...
Dynamical evolution of planetary systems
... the desired result, without any correspondence with the outcomes of N -body simulations (which should be considered as a sort of “ground truth” for dynamical processes). Another problem of the core-accretion model originates from Type-I migration. Type-I migration is the label denoting the radial dr ...
... the desired result, without any correspondence with the outcomes of N -body simulations (which should be considered as a sort of “ground truth” for dynamical processes). Another problem of the core-accretion model originates from Type-I migration. Type-I migration is the label denoting the radial dr ...
What did we learn from transiting planets?
... • Petigura et al. 2013, ApJ, based on Kepler: “We find that 15.1^{+1.8}_{-2.7}% of solar type stars—roughly one in six—has a 1-2 R_E planet with P = 5-50 days. “ • Petigura et al. 2013, PNAS, based on Kepler: “Extrapolating, one finds 5.7^{+1.7}_{-2.2}% of Sun-like stars harbor an Earth-size planet ...
... • Petigura et al. 2013, ApJ, based on Kepler: “We find that 15.1^{+1.8}_{-2.7}% of solar type stars—roughly one in six—has a 1-2 R_E planet with P = 5-50 days. “ • Petigura et al. 2013, PNAS, based on Kepler: “Extrapolating, one finds 5.7^{+1.7}_{-2.2}% of Sun-like stars harbor an Earth-size planet ...
The Next Great Exoplanet Hunt Please share
... around a Sun-like star. For this reason, a meaningful transit survey must include tens of thousands of stars, or more. Because faint stars far outnumber bright ones in any given region of the sky, a practical strategy is to monitor a rich field of relatively faint stars. This is precisely what the K ...
... around a Sun-like star. For this reason, a meaningful transit survey must include tens of thousands of stars, or more. Because faint stars far outnumber bright ones in any given region of the sky, a practical strategy is to monitor a rich field of relatively faint stars. This is precisely what the K ...
Stellar Metamorphosis as Alternative to Nebular Hypothesis
... momentum loss of the Sun.[5] If the nebular model were correct and all the material in the solar system was formed from a giant spinning gas/dust cloud, then the Sun should have the majority of the angular momentum. This means it should spin much more rapidly. The mathematical models have failed to ...
... momentum loss of the Sun.[5] If the nebular model were correct and all the material in the solar system was formed from a giant spinning gas/dust cloud, then the Sun should have the majority of the angular momentum. This means it should spin much more rapidly. The mathematical models have failed to ...
Planet formation
... Snow line: 2.7 AU from the Sun, temperatures are low enough that molecules appear in the form of icy grains, and dust grains have sufficiently low temperatures to capture ice molecules in their mantles. The Snow line is crucial for the planet formation process, as ice-covered grains are suggested to ...
... Snow line: 2.7 AU from the Sun, temperatures are low enough that molecules appear in the form of icy grains, and dust grains have sufficiently low temperatures to capture ice molecules in their mantles. The Snow line is crucial for the planet formation process, as ice-covered grains are suggested to ...
m, a, e
... Only if and when the gap becomes so wide that the near-lying LRs are eliminated, eccentricity is excited. (==> planets larger than 10 m_jup were predicted to be on eccentric orbits (Artymowicz 1992). In practice, this may account for intermediate-e exoplanets. For extremely high e’s we need N-body e ...
... Only if and when the gap becomes so wide that the near-lying LRs are eliminated, eccentricity is excited. (==> planets larger than 10 m_jup were predicted to be on eccentric orbits (Artymowicz 1992). In practice, this may account for intermediate-e exoplanets. For extremely high e’s we need N-body e ...
Bayesian mass and age estimates for transiting exoplanet host stars⋆
... in the mass ratio will give a negligible contribution to the uncertainty on ρ for any star where the presence of an extrasolar planet has been confirmed by radial velocity observations. The same argument applies to brown-dwarf or low mass stellar companions, but some care is needed to make an accur ...
... in the mass ratio will give a negligible contribution to the uncertainty on ρ for any star where the presence of an extrasolar planet has been confirmed by radial velocity observations. The same argument applies to brown-dwarf or low mass stellar companions, but some care is needed to make an accur ...
course objectives - Metropolitan Community College
... COURSE DESCRIPTION: This course is an introductory course in astronomy that covers the tools of astronomy, the night sky, the solar system, stars and star systems, galaxies, and cosmology. This is a lecture-only course. The lab course that complements this course is SCIE 1310. ...
... COURSE DESCRIPTION: This course is an introductory course in astronomy that covers the tools of astronomy, the night sky, the solar system, stars and star systems, galaxies, and cosmology. This is a lecture-only course. The lab course that complements this course is SCIE 1310. ...
Precision age indicators that exploit chemically peculiar stars
... One additional caution about C stars is that they are rare, evolved stars susceptible to stochastic counting effects that can have effects on integrated properties in some cases (Santos & Frogel 1997) though entire, large galaxies are probably immune from stochastic effects. The other, bluer CP stars d ...
... One additional caution about C stars is that they are rare, evolved stars susceptible to stochastic counting effects that can have effects on integrated properties in some cases (Santos & Frogel 1997) though entire, large galaxies are probably immune from stochastic effects. The other, bluer CP stars d ...
Signatures of Planets in Protoplanetary and Debris
... the planet itself and/or the circumplanetary environment heated by the planet, through its contraction and/or via accretion onto it, could be detected. The detection of a gap would already represent a strong indication of the existence of a planet, thus giving information such as planetary mass, dis ...
... the planet itself and/or the circumplanetary environment heated by the planet, through its contraction and/or via accretion onto it, could be detected. The detection of a gap would already represent a strong indication of the existence of a planet, thus giving information such as planetary mass, dis ...
An Unbiased Near-infrared Interferometric Survey for Hot
... (Poynting–Robertson drag) and the evaporation of comets heated when they get close to the Sun supplies dust. While these scenarios might work for a few MIR-detected systems, they generally do not work well for more massive systems, as have been detected in the NIR around other stars. If the dust den ...
... (Poynting–Robertson drag) and the evaporation of comets heated when they get close to the Sun supplies dust. While these scenarios might work for a few MIR-detected systems, they generally do not work well for more massive systems, as have been detected in the NIR around other stars. If the dust den ...
Cosmic variance in [O/Fe] in the Galactic disk
... Galactic Evolution Experiment (APOGEE). We minimize systematic errors by considering groups of stars with similar atmospheric parameters. The APOGEE measurements in the Sloan Digital Sky Survey Data Release 12 reveal that the square root of the star-to-star cosmic variance in the oxygen-to-iron rati ...
... Galactic Evolution Experiment (APOGEE). We minimize systematic errors by considering groups of stars with similar atmospheric parameters. The APOGEE measurements in the Sloan Digital Sky Survey Data Release 12 reveal that the square root of the star-to-star cosmic variance in the oxygen-to-iron rati ...
ISNS3371_041007_bw
... planet in the year 1995. – A planet was discovered in orbit around the star 51 Pegasi. – Over 100 such extrasolar planets are now known to exist. ...
... planet in the year 1995. – A planet was discovered in orbit around the star 51 Pegasi. – Over 100 such extrasolar planets are now known to exist. ...
KINEMATIC DISCOVERY OF A STELLAR STREAM LOCATED IN
... study of the Cetus Polar Stream (CPS). In the CPS study (Yam et al. 2013), we selected metal-poor (−3.0 < [Fe/H] < −1.5) stars with surface gravities consistent with being giants (0 < log g < 4.0) from the Sloan Digital Sky Survey Data Release 8 (SDSS DR8) spectroscopic data in the south Galactic he ...
... study of the Cetus Polar Stream (CPS). In the CPS study (Yam et al. 2013), we selected metal-poor (−3.0 < [Fe/H] < −1.5) stars with surface gravities consistent with being giants (0 < log g < 4.0) from the Sloan Digital Sky Survey Data Release 8 (SDSS DR8) spectroscopic data in the south Galactic he ...
Asynchronous rotation of Earth-mass planets in the habitable zone
... where Ka ≡ (3 M? R3p )/(5ρ̄a3 ), Kg ≡ GM?2 R5p /a6 , G is the universal gravitational constant, M? is the stellar mass, R p , ω, and ρ̄ the planet’s radius, rotation rate, and mean density, and a and n its orbital semi-major axis and mean motion. bg (σ ) characterizes the frequency-(σ -)dependent r ...
... where Ka ≡ (3 M? R3p )/(5ρ̄a3 ), Kg ≡ GM?2 R5p /a6 , G is the universal gravitational constant, M? is the stellar mass, R p , ω, and ρ̄ the planet’s radius, rotation rate, and mean density, and a and n its orbital semi-major axis and mean motion. bg (σ ) characterizes the frequency-(σ -)dependent r ...
11-Massive Stars
... Therefore, they are often easy to resolve spatially despite their typical distance of kiloparsecs. The major question is: are these bipolar outflows driven by the same mechanism as those from low-mass stars? For example, the magnetocentrifugal wind scenarios predicts outflows which are morphological ...
... Therefore, they are often easy to resolve spatially despite their typical distance of kiloparsecs. The major question is: are these bipolar outflows driven by the same mechanism as those from low-mass stars? For example, the magnetocentrifugal wind scenarios predicts outflows which are morphological ...
Circumstellar Disks: IRAS to ALMA (by way of HST) Dr. Karl Stapelfeldt
... nearby molecular clouds (for stars > 1 Lsun) IRAS data allowed astronomers to classify young stellar objects according to IR spectral energy distribution Molecular gas discovered in Class 0, I, and II disks in the 1990s, confirming they could be hosting planet formation ...
... nearby molecular clouds (for stars > 1 Lsun) IRAS data allowed astronomers to classify young stellar objects according to IR spectral energy distribution Molecular gas discovered in Class 0, I, and II disks in the 1990s, confirming they could be hosting planet formation ...
Constraints on the Birth Aggregate of the Solar System
... the binary orbit, the asymptotic incoming velocity vinf of the solar system with respect to the center of mass of the binary, the angles θ, ψ, and φ which describe the impact direction and orientation, and finally the impact parameter h of the collision. Additional (intrinsic) parameters are require ...
... the binary orbit, the asymptotic incoming velocity vinf of the solar system with respect to the center of mass of the binary, the angles θ, ψ, and φ which describe the impact direction and orientation, and finally the impact parameter h of the collision. Additional (intrinsic) parameters are require ...
Unravelling the Origin and Evolution of Our Galaxy
... than our Sun. These are all within a distance of about 100 light-years. The planets detectable by this method are rather massive, comparable to Jupiter (which has about 300 times the mass of Earth). The systems have some surprising properties: two thirds of these giant planets are orbiting their hos ...
... than our Sun. These are all within a distance of about 100 light-years. The planets detectable by this method are rather massive, comparable to Jupiter (which has about 300 times the mass of Earth). The systems have some surprising properties: two thirds of these giant planets are orbiting their hos ...
The extreme ultraviolet and X-ray Sun in Time: High
... decays over time as a result of stellar spin-down. The early Sun’s X-ray (≈1−100 Å) and extreme-ultraviolet (EUV; ≈100−900 Å) emissions could thus have exceeded the present-day Sun’s level by orders of magnitude (Ribas et al. 2005). By driving atmospheric erosion, such extreme radiation levels were ...
... decays over time as a result of stellar spin-down. The early Sun’s X-ray (≈1−100 Å) and extreme-ultraviolet (EUV; ≈100−900 Å) emissions could thus have exceeded the present-day Sun’s level by orders of magnitude (Ribas et al. 2005). By driving atmospheric erosion, such extreme radiation levels were ...
Determining the inclination of the rotation axis of a sun-like Star
... 100 planets detected using radial velocities. However, missions such as COROT, Eddington, and Kepler aim at discovering many such systems. Since for transiting planets ip is known to high accuracy (Brown et al. 2001), a comparison with the independently measured i of the central stars would allow a ...
... 100 planets detected using radial velocities. However, missions such as COROT, Eddington, and Kepler aim at discovering many such systems. Since for transiting planets ip is known to high accuracy (Brown et al. 2001), a comparison with the independently measured i of the central stars would allow a ...
The Final Version of the White Paper is available.
... those in the habitable zones, in terms of chemical composition, stratification and weather. The ultimate goal is the detection of signatures of life. The extremely high signal-to-noise required to detect the exo-planet atmospheric signatures has paradoxically pushed this area into the "photon-starve ...
... those in the habitable zones, in terms of chemical composition, stratification and weather. The ultimate goal is the detection of signatures of life. The extremely high signal-to-noise required to detect the exo-planet atmospheric signatures has paradoxically pushed this area into the "photon-starve ...
Planetary system
A planetary system is a set of gravitationally bound non-stellar objects in orbit around a star or star system. Generally speaking, systems with one or more planets constitute a planetary system, although such systems may also consist of bodies such as dwarf planets, asteroids, natural satellites, meteoroids, comets, planetesimals and circumstellar disks. The Sun together with its planetary system, which includes Earth, is known as the Solar System. The term exoplanetary system is sometimes used in reference to other planetary systems.A total of 1968 exoplanets (in 1248 planetary systems, including 490 multiple planetary systems) have been identified as of 1 October 2015.Of particular interest to astrobiology is the habitable zone of planetary systems where planets could have surface liquid water.