Related papers: Intense Diffuse Far-UV Emission from the Orion Neb…
We have used Voyager and Galex observations to map the diffuse Galactic light near the Galactic equator. We find that most of the observations are relatively faint with surface brightnesses of less than 5,000 photon units. This is important…
Spectra of the magnetic white dwarf binary AM Her were obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) during three consecutive spacecraft orbits. These observations were split into 19 spectra of about 5 min duration (0.025P…
FU Orionis-type stars form a small class of variable Young Stellar Objects, defined by an optical outburst of 5-6 mag followed by gradual fading on a timescale of decades. Since the phenomenon is connected to the circumstellar medium the…
This paper presents an analysis of the UV spectrum of some nebulae with clearly identified illuminating stars, all observed by the IUE satellite. The data show remarkable properties of the UV spectrum of the nebulae. Each spectrum is the…
We re-examine {\em Voyager} Ultraviolet Spectrograph data used to establish upper limits to the $\lambda$ 500-900 \AA and $\lambda$ 900-1100 \AA cosmic diffuse background. The measurement of diffuse flux with the {\em Voyager} UVS data…
Recent analyses of nebular spectra have resulted in discrepant abundances from CNO forbidden and recombination lines. We consider independent methods of determining ion abundances for emission nebulae, comparing ion emission measures with…
The existence of multiple layers in the inner Orion Nebula has been revealed using data from an Atlas of spectra at 2" and 12 km/s resolution. These data were sometimes grouped over Samples of 10"x10"to produce high Signal to Noise spectra…
We report on medium resolution spectrophotometry of the Orion Nebula region, including for the first time the Extended Orion Nebula and the nearby M~43. The 49 long slit observations were divided into 99 smaller samples, which have allowed…
We report the discovery of diffuse hard (1-5 keV) X-ray emission around Jupiter in a deep 160 ks Suzaku XIS data. The emission is distributed over ~16x8 Jovian radius and spatially associated with the radiation belts and the Io Plasma…
We present the result of a systematic search for the iron Kalpha fluorescent line at 6.4 keV among 1616 X-ray sources detected by ultra-deep Chandra observations of the Orion Nebula Cluster and the obscured Orion Molecular Cloud 1…
The IceCube Neutrino Observatory has recently reported strong evidence for neutrino emission from the Galactic plane. The signal is consistent with model predictions of diffuse emission from cosmic ray propagation in the interstellar…
Diffuse Galactic gamma-ray emission is produced in interactions of cosmic rays with gas and ambient photon fields and thus provides us with an indirect measurement of cosmic rays in various locations in the Galaxy. The diffuse gamma-ray…
Far ultraviolet spectra were obtained of the active cool star AB Doradus (HD 36705) during the calibration and checkout period of the FUSE satellite. Observations in this early phase of the mission were taken at a resolving power of…
The predicted emission spectrum of NII is compared with observations of permitted lines in the Orion nebula. Conventional nebular models show that the intensities of the more intense lines can be explained by fluorescence of starlight…
Wide-field (~8' x 8') and deep near-infrared (JHKs bands) polarization images of the Orion nebulae (IRNe) around young stellar objects (YSOs), both massive and low-mass. We found the IRNe around both IRc2 and BN to be very extensive,…
We present images from the Solar Blind Channel on HST that resolve hundreds of far ultraviolet (FUV) emitting stars in two ~1 kpc$^2$ interarm regions of the grand-design spiral M101. The luminosity functions of these stars are compared…
A high spectral resolution observation of the diffuse X-ray background in the 60 - 1000 eV energy range has been made using an array of thirty-six 1 mm^2 micro-calorimeters flown on a sounding rocket. Detector energy resolution ranged from…
We establish that there are two velocity systems along lines-of-sight that contribute to the emission-line spectrum of the the brightest parts of the Orion Nebula. These overlie the Orion-S embedded molecular cloud southwest of the dominant…
The three dimensional structure of the brightest part of the Orion Nebula is assessed in the light of published and new data. We find that the widely accepted model of a concave blister of ionized material needs to be altered in the…
The optical surface brightness of dark nebulae is mainly due to scattering of integrated starlight by classical dust grains. It contains information on the impinging interstellar radiation field, cloud structure, and grain scattering…