A5083124189- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- History and Developments in Astronomy
- Astronomical Observations and Instrumentation
- Molecular Spectroscopy and Structure
- Space Exploration and Technology
- Planetary Science and Exploration
- Atmospheric Ozone and Climate
- Space exploration and regulation
- Solar and Space Plasma Dynamics
- Spectroscopy and Laser Applications
- Isotope Analysis in Ecology
- Adaptive optics and wavefront sensing
- Berry genetics and cultivation research
- Calibration and Measurement Techniques
- Galaxies: Formation, Evolution, Phenomena
- Atomic and Molecular Physics
- Advanced Chemical Physics Studies
- Mass Spectrometry Techniques and Applications
- Growth and nutrition in plants
- Plant Physiology and Cultivation Studies
- Spacecraft Design and Technology
- Spacecraft and Cryogenic Technologies
Vanderbilt University
2012-2023
University of Kentucky
2010
Rice University
1992-2007
Universidad Nacional Autónoma de México
2001-2003
Max Planck Institute for Astronomy
1997-1998
Virginia Tech
1989-1995
Goddard Space Flight Center
1992-1993
University of California, Los Angeles
1985
United States Department of Veterans Affairs
1985
Marshall Space Flight Center
1972-1982
view Abstract Citations (336) References (32) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Discovery of New Objects in the Orion Nebula on HST Images: Shocks, Compact Sources, and Protoplanetary Disks O'Dell, C. R. ; Wen, Zheng Hu, Xihai We have reduced analyzed a set narrow-band images portion M42 south Trapezium. Many new emission-line sources were found, some quite long but so narrow that they are not seen ground-based images. These include thin shells...
view Abstract Citations (306) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Postrefurbishment Mission Hubble Space Telescope Images of the Core Orion Nebula: Proplyds, Herbig-Haro Objects, and Measurements a Circumstellar Disk O'Dell, C. R. ; Wen, Zheng We report on observations M42 made with (HST) immediately after successful repair refurbishment mission. were in strongest optical emission lines H I, (N II), (O III) bandpass close to V. In...
Recent surveys of the Orion Nebula with Hubble Space Telescope have revealed a number stars surrounded by dark silhouettes seen projected against bright background H II region. In this paper, we present detailed analysis HST and ground-based observations six most distinct silhouettes. We find variety morphologies, all consistent thin circumstellar disks spanning range diameters (50 to 1000 AU) inclination angles (0 >80 degrees). The silhouette intensity profiles cannot be fit standard...
New deep narrowband images of the Orion Nebula obtained with WFPC2 on Hubble Space Telescope (HST) and spectra taken HIRES spectrometer at Keck Observatory are presented. We report eight new circumstellar disks seen in silhouette against background nebular light about 30 dark embedded within bright proplyds rimmed by ionization fronts. Deep λ6300 Å reveal skins glowing [O I] emission associated several proplyds. also surrounds one disk not surrounded an front; this object may be...
▪ Abstract The Orion Nebula (M 42) is one of the best studied objects in sky. advent multi-wavelength investigations and quantitative high resolution imaging has produced a rapid improvement our knowledge what widely considered prototype H II region young galactic cluster. Perhaps uniquely among this class object, we have good three dimensional picture nebula, which thin blister ionized gas on front giant molecular cloud, extremely dense associated same processes that produce nebula also...
We report on a survey of the brightest portions Orion Nebula made with Wide Field Planetary Camera 2 Hubble Space Telescope. Fifteen pointings were made, each employing interference filters isolating principal emission lines H I, [N II], and [O III] another an interval similar to V bandpass. A careful compact objects stellar nearly appearance was astrometric solutions for individual fields used determine positions accurate about 0.1". 344 stars measured, down V=22. In addition structures in...
We present the results of spectroscopy four bright proplyds in Orion Nebula obtained at a velocity resolution 6 km s-1. After careful isolation proplyd spectra from confusing nebular radiation, emission-line profiles are compared with those predicted by realistic dynamic/photoionization models objects. The spectral line widths show clear correlation ionization potential, which is consistent free expansion transonic, ionization-stratified, photoevaporating flow. Fitting such flow...
view Abstract Citations (250) References (23) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Distance Scale for Planetary Nebulae Based on Emission-Line Fluxes. O'Dell, Charles Robert discussion of the distance scale and parameters planetary nebulae is given, based previously published new measures flux in H from these objects Both method statistical parallaxes known NGC 246 late-type companion to exciting star are used a calibration An average mass about...
view Abstract Citations (128) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Evolution of the Central Stars Planetary Nebulae. O'Dell, C. R. A new temperature scale for planetary nebulae is derived based upon H recombination line ionized hydrogen nebular shell and photographic magnitude central star. temperatures are systematically larger than those by Berman. mean sizes shells used to indicate time changes occurring in stars. stars seen...
The Cometary Knots in the Helix Nebula have shown themselves observations with Hubble Space Telescope's WFPC2 to be well-resolved photoionized surfaces on central star facing sides of neutral clouds. Material streams backwards from rims ionized surfaces, producing tails. cores are seen extinction against background radiation planetary nebula. Calculations core masses observed indicate about 1.5×l0<SUP>-5</SUP> M<SUB>sun</SUB> for best objects. We detected 313 these objects and project a...
view Abstract Citations (113) References (49) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Three-dimensional Model of the Orion Nebula Wen, Zheng ; O'dell, C. R. We have constructed a geometric model for exploiting fact that most radiation arises from relatively thin layer ionized material near ionization front on side giant molecular cloud OMC-1. As first step, an extinction corrected surface brightness map H alpha emission was combined with point by...
We present HI 21cm observations of the Orion Nebula, obtained with Karl G. Jansky Very Large Array, at an angular resolution 7.2"x5.7" and a velocity 0.77 km/s. Our data reveal absorption towards radio continuum HII region, emission arising from Bar photon-dominated region (PDR) Orion-KL outflow. In PDR, signal peaks in same layer as H2 near-infrared vibrational line emission, agreement models photodissociation H2. The gas temperature this is approximately 540K, abundance interclump PDR...
HST emission-line images of five the arguably closest planetary nebulae have shown that there is a progression characteristics their knots. This begins with dark tangential structures showing no alignment central star and location near main ionization front. At end in largest nebulae, knots are located throughout much ionized zone, where they photoionized on side facing accompanied by long tails well aligned radially. modification what would be expected if were formed or outside front,...
The three-dimensional structure of the brightest part Orion Nebula is assessed in light published and newly established data. We find that widely accepted model a concave blister ionized material needs to be altered southwest direction from Trapezium, where we Orion-S feature separate cloud very optically thick molecules within body gas, which probably location multiple embedded sources produce optical molecular outflows define star formation region. Evidence for this comes presence H2CO...
view Abstract Citations (120) References (14) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Photoelectirc Spectrophotometry of Gaseous Nebulae. I. The Orion Nebula. O'Dell, C. R. ; Hubbard, W. B. strength and energy distribution in the continuous radiation Nebula was investigated by photoelectric-filter photometry photographic spectrophotometry for five regions widely varying conditions surface brightness. It is shown that continuum becomes very blue strong...
The Hubble Space Telescope (HST) Treasury Program on the Orion Nebula Cluster has used 104 orbits of HST time to image Great region with Advanced Camera for Surveys (ACS), Wide-Field/Planetary 2 (WFPC2) and Near Infrared Multi Object Spectrograph (NICMOS) instruments in 11 filters ranging from U-band H-band equivalent HST. program been intended perform definitive study stellar component ONC at visible wavelengths, addressing key questions like cluster IMF, age spread, mass accretion,...
view Abstract Citations (82) References (28) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Planetary Nebula in the Globular Cluster M15. O'Dell, C. R. ; Peimbert, M. Kinman, T. D. results of a photographic spectrophotometric investigation nebulous object K648 globular cluster M15 are presented. On basis discussion size, density, and mass it is shown that represents typical example planetary nebula phenomena. relative abundances hydrogen, helium, oxygen,...
view Abstract Citations (59) References (8) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Emission-Band and Continuum Photometry of Comet Seki (1961f). O'Dell, C. R. ; Osterbrock, D. E. Measurements were made through interference filters centered on the C2 X 4737 sequence continuum near 4470, diaphragms various diameters The measurements calibrated in energy units by means a spectral scan same region comet at time as filter stars with known distributions....
Abstract The common assumption that <?CDATA ${\theta }^{1}\,\mathrm{Ori}\,{\rm{C}}$?> is the dominant ionizing source for Orion Nebula critically examined. This underlies much of existing analysis nebula. In this paper we establish through comparison relative strengths emission lines with expectations from Cloudy models and direction bright edges proplyds }^{2}\,\mathrm{Ori}\,{\rm{A}}$?> , which lies beyond Bright Bar, also plays an important role. does dominate ionization in inner part...
Hubble Space Telescope Planetary Camera images have been used to quantitatively determine key parameters characterizing emission-line proplyds in the Orion Nebula. A previous conclusion that objects are radiation-bounded ionization fronts is confirmed and found be excellent agreement with observations. Only a very loose correlation of proplyd size distance from ionizing star θ1 Ori C was found. The brightness distribution around bright cusp facing not simple spherical models. along radial...
The optical appearance of the Orion Nebula is significantly altered by presence interstellar extinction. Since high above Galactic plane and nearby, most this extinction due to material immediately in front associated star cluster. This fundamentally alters Nebula. We have quantitatively determined correction comparing surface brightness nebula at a resolution about 17 radio continuum Hα emission line. results compare well with new determinations made from Hβ line ratios....
We present Spitzer Space Telescope observations of 11 regions SE the Bright Bar in Orion Nebula, along a radial from exciting star theta1OriC, extending 2.6 to 12.1'. Our Cycle 5 programme obtained deep spectra with matching IRS short-high (SH) and long-high (LH) aperture grid patterns. Most previous IR missions observed only inner few arcmin. is benchmark for studies ISM particularly elemental abundances. provide unique perspective on Ne S abundances by virtue observing dominant ionization...
My life has been an interesting voyage. I became astronomer because could not imagine living on Earth and trying to understand how the Universe works. scientific career revolved around observing motions of stars within galaxies ...Read More