A Population of planetary systems characterized by short-period, Earth-sized planets
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Jason H. Steffen↗
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The discovery and legacy of Kepler’s multi-transiting planetary systems
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Jason H. Steffen↗
Planetary systems associated with main-sequence stars.
Luminosity function used to estimate invisible planet-like objects in sun neighborhood in relation to main sequence stars
MAIN SEQUENCE STAR↗
Fiber optics systems for planetary scan system final technical report
Optical tracking and detector system with fiber optics cone for Mariner B spacecraft
OPTICAL TRACKING↗
Pulsar planetary systems
Pulsar formation effect on orbits of preexisting planets and postformation planets effects on pulsar period and phase residuals
Michel, F. C.↗
The influence of the great inequality on the secular disturbing function of the planetary system
Influence of great equality between Jupiter and Saturn on secular disturbing function of principal planets
Musen, P.↗
Concerning the planetary system of Barnard's Star.
Reanalyzed data pertaining to the proper motion of Barnard's Star indicate that at least two dark companions are required to explain the observations. It is found that the orbits of the two companions are not coplanar, but have a relative inclination of nearly 50 deg.
Black, D. C.↗
Interpretation of epsilon Aurigae. II - Infrared excess, secondary light variations, and plausible formation of a planetary system
Infrared excess based on the disk model proposed in a previous paper was computed. It was found that the disk alone will emit infrared radiation below the margin of detection. However, if individual condensations are present, the combined result of the disk proper and the condensations yields results of infrared excesses that are consistent with observations. The presence of condensations also makes the secondary light variation understandable. An elementary theory is developed that analyzes such light variations. The result of the analysis yields the size of the orbit of the condensation around the secondary component.
Huang, S.-S.↗
Solar nebula dispersal and the stability of the planetary system. I - Scanning secular resonance theory
Secular resonances in the early solar system are investigated with the aim of establishing constraints on the time scale and method of solar nebula dispersal. Simplified nebula models and dispersal routines are used to approximate changes in an assumed axisymmetric nebula potential. These changes drive an evolutionary sequence of Laplace-Lagrange solutions for the secular variations of the solar system. These sequences are characterized by a sweep of one or more giant planet resonances through the inner solar system. Their effect is rate-dependent; characteristic dispersal times of not greater than 10,000 to 100,000 years are required to avoid the generation of terrestrial eccentricities and inclinations in excess of observed values.
Ward, W. R.↗
IUE observations of Beta Pictoris - An IRAS candidate for a proto-planetary system
The results of a preliminary analysis of high-resolution and low-resolution UV spectra of the edge-on extended-disk shell star Beta Pic, obtained with the IUE SWP and LWR instruments on November 5-6, 1984, are reported and compared with IRAS and ground-based observations. No selective UV extinction is detected, and the fine structure of the Fe II and C I absorption lines and the presence of metastable Fe II lines are considered consistent with a circumstellar nebula or extended envelope of density greater than 1000/cu cm and electron density (1-10) x 10 to the 8th/cu cm or less at 1-2 AU from the central star. The possibility that the extended orbiting disk is clumpy, as observed by Smith and Terrile (1985), is discussed.
Kondo, Y.↗
Direct imaging of extra-solar planetary systems with the Circumstellar Imaging Telescope (CIT)
In a joint study conducted by the Jet Propulsion Laboratory and the Perkin-Elmer Corporation it was found that an earth orbital, 1.5 meter diameter low scattered light coronagraphic telescope can achieve a broad range of scientific objectives including the direct detection of Jupiter-sized planets around the nearby stars. Recent major advances in the understanding of coronagraphic performance and in the field of super smooth mirror fabrication allow such an instrument to be designed and built within current technology. Such a project, called the Circumstellar Imaging Telescope (CIT), is currently being proposed.
Terrile, Richard J.↗
Space Station Astrometric Telescope tracking for the detection of planetary systems
The paper presents a comprehensive star observation and tracking strategy, which uses a computer simulation of the Space Station orbital mechanics, system constraints, and Astrometric Telescope Facility (ATF) tracking maneuvers over a long observational period. This approach may be used to obtain data which may assist in the preliminary systems definition of the ATF. Results are given for an analysis which uses a restricted target set in order to demonstrate the disproportionate effect of the galactic-photon-rate index on the observation times for each star.
Mascy, Alfred C.↗
The impact of stellar evolution on planetary system development
The connection between stellar evolution and planet formation is investigated. Particular attention is given to the problem posed by the fact that the formation of Jupiter occurred before the formation of Mars and that the formation of the solid core of Saturn was completed before the dissipation of the gas in the nebula. Several possible solutions to this problem are suggested.
Bodenheimer, Peter↗
Imaging other planetary systems from the moon
This paper studies the problem of using a telescope like the HST, only larger and sensitive to a wider range of wavelengths, to image systems of planets like the solar system around other stars. Both reflected starlight and thermal radiation from the planets are treated. The instrumental effects of aperture diffraction, scattering due to the power spectral density of telescope mirror surface errors, and telescope thermal emission are included. The integration time required to achieve a signal-to-noise ratio is computed at 5 for photon-statistical random errors only, which is a necessary but not sufficient criterion for detection at a confidence level of five standard deviations. A cold telescope on the moon with 16m aperture and the optical quality of HST could detect and characterize planets around nearby stars.
Brown, Robert A.↗
A observational test for the existence of a planetary system orbiting PSR1257 + 12
It is pointed out that, because of the near commensurability of the orbital periods of the recently reported planets of the nearby millisecond pulsar PSR1257 + 12, the mutual gravitational perturbations of the two planets should produce not only small secular changes, but also larger periodic changes in their orbital elements. In particular, it is found that changes in the eccentricities and orbital periods should become measurable within a few years. Such a measurement would help determine the three masses in the system and the inclinations of the orbits. More important, a detection of these changes, if they agree with theoretical predictions presented here, should provide irrefutable confirmation that the periodic residuals are caused by orbiting planets rather than some other effect.
Rasio, F. A.↗
Space optics for studying extra-solar planetary systems
The sharp imaging of telescopes in space will improve the ability to see faint objects near bright ones. One exciting application is the search for planets around other stars. However, because a planet is, at best, 10 exp 9 times fainter than a star in visible light, specialized optical systems are required. Using apodization to remove diffracted light, the limiting source of noise is the intensity of starlight scattered by mirror figure errors. Based on the prelaunch metrology of the HST mirrors, and considering only photonstatistics, months of integration would be needed for HST to detect Jupiter next to the sun at a distance of 5 pc. The integration times will be shorter for future telescopes in space with smoother mirrors and/or larger apertures.
Brown, Robert A.↗
Dynamics of binary and planetary-system interaction with disks - Eccentricity changes
Protostellar and protoplanetary systems, as well as merging galactic nuclei, often interact tidally and resonantly with the astrophysical disks via gravity. Underlying our understanding of the formation processes of stars, planets, and some galaxies is a dynamical theory of such interactions. Its main goals are to determine the geometry of the binary-disk system and, through the torque calculations, the rate of change of orbital elements of the components. We present some recent developments in this field concentrating on eccentricity driving mechanisms in protoplanetary and protobinary systems. In those two types of systems the result of the interaction is opposite. A small body embedded in a disk suffers a decrease of orbital eccentricity, whereas newly formed binary stars surrounded by protostellar disks may undergo a significant orbital evolution increasing their eccentricities.
Atrymowicz, Pawel↗
Orbital evolution of the PSR1257+12 planetary system
The detection of orbital perturbation effects in the PSR1257+12 timing data would provide irrefutable confirmation that planets are indeed orbiting the pulsar. Here we give an overview of how perturbation effects are expected to affect the orbital elements of the two planets over the next few years. In particular, we give a simple calculation of resonant perturbations, including the nonlinear effects which could be important if sin i less than about 0.1. We also present a new analysis of the effects of close encounters between the two planets and we discuss their detectability.
Rasio, Frederic A.↗