17 results match your criteria Astronomical Journal[Journal]

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NEW YOUNG STARS AND BROWN DWARFS IN THE UPPER SCORPIUS ASSOCIATION.

Astron J 2018 Aug 27;156(2). Epub 2018 Jul 27.

Department of Physics, Rockhurst University, 1100 Rockhurst Rd, Kansas City, MO 64110-2508, USA.

To improve the census of the Upper Sco association (~11 Myr, ~145 pc), we have identified candidate members using parallaxes, proper motions, and color-magnitude diagrams from several wide-field imaging surveys and have obtained optical and infrared spectra of several hundred candidates to measure their spectral types and assess their membership. We also have performed spectroscopy on a smaller sample of previously known or suspected members to refine their spectral types and evidence of membership. We have classified 530 targets as members of Upper Sco, 377 of which lack previous spectroscopy. Read More

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http://dx.doi.org/10.3847/1538-3881/aacc6dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6317747PMC

A New, Long-Lived, Jupiter Mesoscale Wave Observed at Visible Wavelengths.

Astron J 2018 Aug 2;156(2). Epub 2018 Aug 2.

Fundació Observatori Esteve Duran, Barcelona, Spain.

Small-scale waves were observed along the boundary between Jupiter's North Equatorial Belt and North Tropical Zone, ~16.5° N planetographic latitude in Hubble Space Telescope data in 2012 and throughout 2015 to 2018, observable at all wavelengths from the UV to the near IR. At peak visibility, the waves have sufficient contrast (~10%) to be observed from ground-based telescopes. Read More

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http://dx.doi.org/10.3847/1538-3881/aacaf5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6268009PMC
August 2018
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Jupiter's Mesoscale Waves Observed at 5 m by Ground-based Observations and JIRAM.

Astron J 2018 Aug 26;156(2). Epub 2018 Jul 26.

INAF-Istituto di Astrofisica e Planetologia Spaziali, Roma, Italy.

We characterize the origin and evolution of a mesoscale wave pattern in Jupiter's North Equatorial Belt (NEB), detected for the first time at 5 m using a 2016-17 campaign of "lucky imaging" from the VISIR instrument on the Very Large Telescope and the NIRI instrument on the Gemini observatory, coupled with -band imaging from Juno's JIRAM instrument during the first seven Juno orbits. The wave is compact, with a 1°.1-1°. Read More

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http://dx.doi.org/10.3847/1538-3881/aace02DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6267995PMC
August 2018
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Spectroscopic Characterization of Key Aromatic Molecules: A Route toward The Origin of Life.

Astron J 2017 Aug;154(3)

Department of Physics, University of Maryland, College Park, MD 20742, USA.

To gain information on the abiotic synthesis of the building blocks of life from simple molecules, and their subsequent chemical evolution to biological systems, the starting point is the identification of target species in Titan-like planets, i.e., planets that resemble the primitive Earth, as well as in Earth-like planets in the habitable zone of their star, namely planets where life can be already originated. Read More

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5881883PMC
August 2017
2 Reads

FUSE Spectroscopy of the Accreting Hot Components in Symbiotic Variables.

Astron J 2017 Apr 17;153(No 4). Epub 2017 Mar 17.

Department of Physics & Astronomy, Florida Institute of Technology, Melbourne, FL 98195, USA.

We have conducted a spectroscopic analysis of the far ultraviolet archival spectra of four symbiotic variables, EG And, AE Ara, CQ Dra and RW Hya. RW Hya and EG And have never had a recorded outburst while CQ Dra and AE Ara have outburst histories. We analyze these systems while they are in quiescence in order to help reveal the physical properties of their hot components via comparisons of the observations with optically thick accretion disk models and NLTE model white dwarf photospheres. Read More

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http://dx.doi.org/10.3847/1538-3881/aa62a9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5810147PMC

Far Ultraviolet Spectroscopy of Old Novae. II. RR Pic, V533 Her, and DI Lac.

Astron J 2017 Mar 15;153(No 3). Epub 2017 Feb 15.

Department of Astrophysics & Planetary Science, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085, USA.

The old novae V533 Her (Nova Her 1963), DI Lac (Nova Lac 1910), and RR Pic (Nova Pic 1891) are in (or near) their quiescent stage, following their nova explosions, and continue to accrete at a high rate in the aftermath of their explosions. They exhibit continua that are steeply rising into the FUV, as well as absorption lines and emission lines of uncertain origin. All three have () spectra that offer not only higher spectral resolution but also wavelength coverage extending down to the Lyman Limit. Read More

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http://dx.doi.org/10.3847/1538-3881/153/3/109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5810142PMC

Hubble COS Spectroscopy of the Dwarf Nova CW Mon: The White Dwarf in Quiescence?

Astron J 2017 Aug 13;154(2). Epub 2017 Jul 13.

Department of Physics, University of Warwick, Coventry CV4 7AL, UK.

We present a synthetic spectral analysis of the HST COS spectrum of the U Geminorum-type dwarf nova CW Mon, taken during quiescence as part of our COS survey of accreting white dwarfs in Cataclysmic Variables. We use synthetic photosphere and optically thick accretion disk spectra to model the COS spectrum as well as archival IUE spectra obtained decades ago when the system was in an even deeper quiescent state. Assuming a reddening of E(B-V)=0. Read More

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http://dx.doi.org/10.3847/1538-3881/aa774cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5804891PMC

A SEARCH FOR LOST PLANETS IN THE MULTI-PLANET SYSTEMS AND THE DISCOVERY OF A LONG PERIOD, NEPTUNE-SIZED EXOPLANET KEPLER-150 F.

Astron J 2017 Apr 28;153(No 4). Epub 2017 Mar 28.

Department of Astronomy, Yale University, New Haven, CT 06511 USA.

The vast majority of the 4700 confirmed planets and planet candidates discovered by the space telescope were first found by the pipeline. In the pipeline, after a transit signal is found, all data points associated with those transits are removed, creating a "Swiss cheese"-like light curve full of holes, which is then used for subsequent transit searches. These holes could render an additional planet undetectable (or "lost"). Read More

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http://dx.doi.org/10.3847/1538-3881/aa62adDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5783551PMC

Second Epoch VLBA Calibrator Survey Observations - VCS-II.

Astron J 2016 May;151(6)

National Science Foundation, Washington, DC,

Six very successful VLBA calibrator survey campaigns were run between 1994 and 2007 to build up a large list of compact radio sources with positions precise enough for use as VLBI phase reference calibrators. We report on the results of a second epoch VLBA Calibrator Survey campaign (VCS-II) in which 2400 VCS sources were re-observed at X and S bands in order to improve the upcoming third realization of the International Celestial Reference Frame (ICRF3) as well as to improve their usefulness as VLBI phase reference calibrators. In this survey, some 2062 previously detected sources and 324 previously undetected sources were detected and revised positions are presented. Read More

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http://dx.doi.org/10.3847/0004-6256/151/6/154DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6010998PMC

Far Ultraviolet Spectroscopy of Old Novae I. V603 Aquila.

Astron J 2015 Jul 7;150(No 1). Epub 2015 Jul 7.

Astrophysics & Planetary Science, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085, USA.

We present the results of a synthetic spectral analysis of the far ultraviolet archival IUE, HST and FUSE observations of the fast old nova V603 Aql, obtained some 90 years after its 1918 nova outburst. Our analysis utilizes the new Hubble FGS parallax distance for this nearly face-on old nova, a high white dwarf mass and a low reddening. Our analysis includes non-truncated optically thick accretion disks since V603 Aql is neither a polar nor an intermediate polar. Read More

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http://dx.doi.org/10.1088/0004-6256/150/1/36DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5810146PMC

2MASS J035523.37+113343.7: A YOUNG, DUSTY, NEARBY, ISOLATED BROWN DWARF RESEMBLING A GIANT EXOPLANET.

Astron J 2013 20;2. Epub 2012 Nov 20.

Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10034.

We present parallax and proper motion measurements, near-infrared spectra, and WISE photometry for the low surface gravity L5 dwarf 2MASSJ035523.37+113343.7 (2M0355). Read More

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http://stacks.iop.org/1538-3881/145/i=1/a=2?key=crossref.2df
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http://dx.doi.org/10.1088/0004-6256/145/1/2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294310PMC
November 2012

DISCOVERY OF TWO VERY WIDE BINARIES WITH ULTRACOOL COMPANIONS AND A NEW BROWN DWARF AT THE L/T TRANSITION.

Astron J 2012 ;144(6)

Departamento de Física y Astronomía, Facultad de Ciencias, Universidad de Valparaíso, Av. Gran Bretaña 1111, Playa Ancha, Casilla 53, Valparaíso, Chile.

We present the discovery and spectroscopic follow-up of a nearby late-type L dwarf (2M0614+3950), and two extremely wide very-low-mass binary systems (2M0525-7425AB and 2M1348-1344AB), resulting from our search for common proper motion pairs containing ultracool components in the Two Micron All Sky Survey (2MASS) and the Wide-field Infrared Survey Explorer (WISE) catalogs. The near-infrared spectrum of 2M0614+3950 indicates a spectral type L9 ± 1 object residing at a distance of 26.0 ± 1. Read More

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http://dx.doi.org/10.1088/0004-6256/144/6/180DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294308PMC
January 2012

H2O ice in the envelopes of OH/IR stars.

Astron J 1998 Jun;115(6):2509-14

Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA.

In an attempt to better understand the conditions under which molecules condense onto grains in the envelopes of evolved stars, we have searched for the presence of H2O ice in the circumstellar envelopes of several evolved (OH/IR) stars. The sample of stars observed was selected on the basis of mass-loss rates, luminosities, and outflow velocities in order to cover a range of physical conditions that might affect the amount of ice present in stellar envelopes. Despite the clear presence of H2O ice around other, previously observed, evolved stars, our search in six OH/IR stars has resulted in only one clear detection, in OH 26. Read More

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The dust coma of Comet P/Giacobini-Zinner in the infrared.

Astron J 1992 Jul;104(1):386-93

Jet Propulsion Laboratory, California Institute of Technology, Pasadena 91109.

We present 1-20 micrometers photometry of P/Giacobini-Zinner obtained at the NASA Infrared Telescope Facility, during 1985 June-September (r = 1.57-1.03 AU). Read More

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A survey of cyclopropenylidene (C3H2) in galactic sources.

Astron J 1989 May;97(5):1403-22

Department of Physics and Astronomy, University of Massachusetts, Amherst 01003, USA.

We report the results of an initial survey in a variety of Galactic sources for cyclopropenylidene (C3H2), the first interstellar hydrocarbon ring molecule. C3H2 is found to be very widespread throughout the Galaxy. This, together with its large dipole moment and many observable transitions, makes cyclopropenylidene a promising probe for physical conditions in the interstellar medium. Read More

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May 1989
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Radiometry of near-earth asteroids.

Astron J 1989 Apr;97(4):1211-9

Jet Propulsion Laboratory, California Institute of Technology, Pasadena 91109, USA.

We report 10 micrometers infrared photometry for 22 Aten, Apollo, and Amor asteroids. Thermal models are used to derive the corresponding radiometric albedos and diameters. Several of these asteroids appear to have surfaces of relatively high thermal inertia due to the exposure of bare rock or a coarse regolith. Read More

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April 1989
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Comet Sugano-Saigusa-Fujikawa (1983V)--a small, puzzling comet.

Astron J 1987 Oct;94(4):1081-7

Jet Propulsion Laboratory, California Institute of Technology, Pasadena 91109, USA.

Spectroscopic and infrared observations of Comet Sugano-Saigusa-Fujikawa (1983V) were obtained during its close approach to the Earth on 11-14 June 1983. The [O I] production rates of 1.8 +/- 0. Read More

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October 1987
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