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- ID:
- ivo://CDS.VizieR/J/A+A/454/683
- Title:
- Position of Uranian satellites
- Short Name:
- J/A+A/454/683
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Puck, a faint satellite very close to Uranus' planet, was discovered by Voyager 2 Spacecraft images in 1986. Ever since then, few observations from Earth have been made. This prompted us to start a program of systematic observations of this satellite with the 1.6m telescope at the Laboratorio Nacional de Astrofisica/MCT (Itajuba, Brazil). The success of the observations is mainly due to the use of a Coronagraph developed at Observatorio Nacional/MCT (Rio de Janeiro, Brazil). This article presents astrometric positions obtained from Earth observations of Puck and of the five major Uranian satellites for four nights in 2004. Those positions are compared to the theoretically calculated positions from JPL Development Ephemeris. For Puck, the root mean square (rms) of the mean residual was found to be 84 milliarcseconds (mas). The stars' USNO-A2.0 catalog (<I/252>) was used as a reference system for the astrometric calibration.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2214
- Title:
- Positions of Saturn and its satellites in 2002-2006
- Short Name:
- J/AJ/136/2214
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents 2154 precise positions of Saturn and its major satellites from 359 CCD exposures taken with the 1m telescope at the Yunnan Observatory during the years 2002-2006.
- ID:
- ivo://CDS.VizieR/J/other/KFNT/15.483
- Title:
- Positions of Thebe and Amalthea
- Short Name:
- J/other/KFNT/15.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The file jovsat.dat contains 35 intersatellite positions of inner Jovian moons Thebe and Amalthea, derived from the observations made with the 2-m Zeiss RCC telescope of Terskol Observatory (Terskol peak, Northern Caucasus, long=42.50083{deg}, lat= 43.27427{deg}, h=3100m) in 1998. The Two-Channel Focal Reducer of the Max-Planck Institute for Aeronomy (MPAe,Germany) was used for acquisition of the images. We provide delta(alpha) and delta(delta) of Thebe and Amalthea with respect to the Galilean satellites, that were used as the reference points forming the reference direction on the frames. Astrometric topocentric coordinates J2000.0 of the Galilean satellites were used for scale and orientation angle determination. The array scale was corrected for differential refraction and differential aberration to first-order. All observed positions are compared with the theoretical ones.
- ID:
- ivo://CDS.VizieR/J/MNRAS/441/3543
- Title:
- Possible planets around A stars
- Short Name:
- J/MNRAS/441/3543
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Kepler photometry of A stars shows that a considerable fraction (about 19 per cent) have a peculiar feature in the periodogram. This feature consists of a broad peak, thought to be due to differential rotation in a spotted star, and a sharp peak at slightly higher frequency. The pattern clearly involves some widespread stellar property and the sharp peak implies a strictly coherent periodicity. We investigate the possibility that the periodicity is due to rotation, pulsation or an orbital effect. We argue that neither rotation nor pulsation can provide a suitable, testable, explanation. We suggest that the sharp feature could be due to a planet in synchronous orbit around the rapidly rotating, spotted A star, not necessarily in transit. Spectroscopic observations of sufficient precision are required to falsify this hypothesis.
- ID:
- ivo://CDS.VizieR/J/ApJ/796/48
- Title:
- Potential exoplanet targets with Palomar/TripleSpec
- Short Name:
- J/ApJ/796/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Here we explore the capabilities of NASA's 3.0 m Infrared Telescope Facility (IRTF) and SpeX spectrometer and the 5.08 m Hale telescope with the TripleSpec spectrometer with near-infrared H-, K-, and L-band measurements of HD 209458b's secondary eclipse. Our IRTF/SpeX data are the first absolute L-band spectroscopic emission measurements of any exoplanet other than the hot Jupiter HD 189733b. Previous measurements of HD 189733b's L band indicate bright emission hypothesized to result from non-LTE CH_4_{nu}_3_ fluorescence. We do not detect a similar bright 3.3 {mu}m feature to ~3{sigma}, suggesting that fluorescence does not need to be invoked to explain HD 209458b's L-band measurements. The validity of our observation and reduction techniques, which decrease the flux variance by up to 2.8 orders of magnitude, is reinforced by 1{sigma} agreement with existent Hubble/NICMOS and Spitzer/IRAC1 observations that overlap the H, K, and L bands, suggesting that both IRTF/SpeX and Palomar/TripleSpec can measure an exoplanet's emission with high precision.
- ID:
- ivo://CDS.VizieR/J/ApJ/807/45
- Title:
- Potentially habitable planets orbiting M dwarfs
- Short Name:
- J/ApJ/807/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an improved estimate of the occurrence rate of small planets orbiting small stars by searching the full four-year Kepler data set for transiting planets using our own planet detection pipeline and conducting transit injection and recovery simulations to empirically measure the search completeness of our pipeline. We identified 156 planet candidates, including one object that was not previously identified as a Kepler Object of Interest. We inspected all publicly available follow-up images, observing notes, and centroid analyses, and corrected for the likelihood of false positives. We evaluated the sensitivity of our detection pipeline on a star-by-star basis by injecting 2000 transit signals into the light curve of each target star. For periods shorter than 50 days, we find 0.56^+0.06^_-0.05_ Earth-size planets (1-1.5R_{Earth}_) and 0.46^+0.07^_-0.05_ super-Earths (1.5-2R_{Earth}_) per M dwarf. In total, we estimate a cumulative planet occurrence rate of 2.5+/-0.2 planets per M dwarf with radii 1-4R_{Earth}_ and periods shorter than 200 days. Within a conservatively defined habitable zone (HZ) based on the moist greenhouse inner limit and maximum greenhouse outer limit, we estimate an occurrence rate of 0.16^+0.17^_-0.07_ Earth-size planets and 0.12^+0.10^_-0.05_ super-Earths per M dwarf HZ. Adopting the broader insolation boundaries of the recent Venus and early Mars limits yields a higher estimate of 0.24^+0.18^_-0.08_ Earth-size planets and 0.21^+0.11^_-0.06_ super-Earths per M dwarf HZ. This suggests that the nearest potentially habitable non-transiting and transiting Earth-size planets are 2.6+/-0.4pc and 10.6^+1.6^_-1.8_pc away, respectively. If we include super-Earths, these distances diminish to 2.1+/-0.2pc and 8.6^+0.7^_-0.8_pc.
- ID:
- ivo://CDS.VizieR/J/ApJS/217/18
- Title:
- Potential transit signals in Kepler Q1-Q17
- Short Name:
- J/ApJS/217/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for potential transit signals in the full 17-quarter data set collected during Kepler's primary mission that ended on 2013 May 11, due to the on board failure of a second reaction wheel needed to maintain high precision, fixed, pointing. The search includes a total of 198646 targets, of which 112001 were observed in every quarter and 86645 were observed in a subset of the 17 quarters. For the first time, this multi-quarter search is performed on data that have been fully and uniformly reprocessed through the newly released version of the Data Processing Pipeline. We find a total of 12669 targets that contain at least one signal that meets our detection criteria: periodicity of the signal, a minimum of three transit events, an acceptable signal-to-noise ratio, and four consistency tests that suppress many false positives. Each target containing at least one transit-like pulse sequence is searched repeatedly for other signals that meet the detection criteria, indicating a multiple planet system. This multiple planet search adds an additional 7698 transit-like signatures for a total of 20367. Comparison of this set of detected signals with a set of known and vetted transiting planet signatures in the Kepler field of view shows that the recovery rate of the search is 90.3%. We review ensemble properties of the detected signals and present various metrics useful in validating these potential planetary signals. We highlight previously undetected transit-like signatures, including several that may represent small objects in the habitable zone of their host stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/759/19
- Title:
- Precise radial velocities of {rho}^1^ Cancri
- Short Name:
- J/ApJ/759/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a mass determination for the transiting super-Earth {rho}^1^ Cancri e based on nearly 700 precise radial velocity (RV) measurements. This extensive RV data set consists of data collected by the McDonald Observatory planet search and published data from Lick and Keck observatories. We obtained 212 RV measurements with the Tull Coud\'e Spectrograph at the Harlan J. Smith 2.7m Telescope and combined them with a new Doppler reduction of the 131 spectra that we have taken in 2003-2004 with the High-Resolution Spectrograph (HRS) at the Hobby-Eberly Telescope for the original discovery of {rho}^1^ Cancri e. Using this large data set we obtain a five-planet Keplerian orbital solution for the system and measure an RV semi-amplitude of K=6.29+/-0.21m/s for {rho}^1^ Cnc e and determine a mass of 8.37+/-0.38M_{oplus}_. The uncertainty in mass is thus less than 5%. This planet was previously found to transit its parent star, which allowed them to estimate its radius. Combined with the latest radius estimate from Gillon et al. (Cat. J/A+A/539/A28), we obtain a mean density of {rho}=4.50+/-0.20g/cm3. The location of {rho}^1^ Cnc e in the mass-radius diagram suggests that the planet contains a significant amount of volatiles, possibly a water-rich envelope surrounding a rocky core.
- ID:
- ivo://CDS.VizieR/J/ApJ/715/1050
- Title:
- Predicted abundances for extrasolar planets. I.
- Short Name:
- J/ApJ/715/1050
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extrasolar planet host stars have been found to be enriched in key planet-building elements. These enrichments have the potential to drastically alter the composition of material available for terrestrial planet formation. Here, we report on the combination of dynamical models of late-stage terrestrial planet formation within known extrasolar planetary systems with chemical equilibrium models of the composition of solid material within the disk. This allows us to determine the bulk elemental composition of simulated extrasolar terrestrial planets. A wide variety of resulting planetary compositions are found, ranging from those that are essentially "Earth like", containing metallic Fe and Mg silicates, to those that are dominated by graphite and SiC. This shows that a diverse range of terrestrial planets may exist within extrasolar planetary systems.