248 research outputs found
EPA/ECLSS consumables analyses for the Spacelab 1 flight
The results of electrical power system (EPS) and environmental control/life support system (ECLSS) consumables analyses of the Spacelab 1 mission are presented. The analyses were performed to assess the capability of the orbiter systems to support the proposed mission and to establish the various non propulsive consumables requirements. The EPS analysis was performed using the shuttle electrical power system (SEPS) analysis computer program. The ECLSS analysis was performed using the shuttle environmental consumables requirements evaluation tool (SECRET) program
A spherical lamellar grating interferometer for airborne astronomical observations of far infrared objects
A lamellar grating has been developed to be used for very far infrared observations on the airborne observatory. The design characteristics and performance during laboratory testing and initial observations of Jupiter at wavelengths between 50 and 500 microns are presented
Spitzer Mid-Infrared Imaging of Nearby Ultraluminous Infrared Galaxies
We have observed 14 nearby (z<0.16) Ultraluminous Infrared Galaxies (ULIRGs)
with Spitzer at 3.6-24 microns. The underlying host galaxies are well-detected,
in addition to the luminous nuclear cores. While the spatial resolution of
Spitzer is poor, the great sensitivity of the data reveals the underlying
galaxy merger remnant, and provides the first look at off-nuclear mid-infrared
activity.Comment: To appear in the conference proceedings for Spitzer New Views of the
Universe, held Nov. 2004 in Pasadena, C
Abundances in galactic H2 regions, 3: G25.4-0.2, G45.5+0.06, M8, S159 and DR22
Measurements of the ARII (6.99 microns), ArIII (8.99 microns), NeII (12.81 microns), SIII (18.71 microns), and SIV (10.51 microns) lines are presented for five compact HII regions along with continuum spectroscopy. From these data and radio data, lower limits to the elemental abundances of Ar, S, and Ne were deduced. The complex G25.4-0.2 is only 5.5 kpc from the galactic center, and is considerably overabundant in all these elements. Complex G45.5+0.06 is at seven kpc from the galactic center, and appears to be approximately consistent with solar abundance. The complex S159 in the Perseus Arm, at 12 kpc from the galactic center, has solar abundance, while M8 in the solar neighborhood may be somewhat overabundant in Ar and Ne. Complex DR 22, at 10 kpc from the galactic center in the Cygnus Arm, is overabundant in Ar. A summary of results from a series of papers on abundances is given
A Structural Analysis of Star-Forming Region AFGL 490
We present Spitzer IRAC and MIPS observations of the star-forming region
containing intermediate-mass young stellar object (YSO) AFGL 490. We supplement
these data with near-IR 2MASS photometry and with deep SQIID observations off
the central high extinction region. We have more than doubled the known
membership of this region to 57 Class I and 303 Class II YSOs via the combined
1-24 um photometric catalog derived from these data. We construct and analyze
the minimum spanning tree of their projected positions, isolating one locally
over-dense cluster core containing 219 YSOs (60.8% of the region's members). We
find this cluster core to be larger yet less dense than similarly analyzed
clusters. Although the structure of this cluster core appears irregular, we
demonstrate that the parsec-scale surface densities of both YSOs and gas are
correlated with a power law slope of 2.8, as found for other similarly analyzed
nearby molecular clouds. We also explore the mass segregation implications of
AFGL 490's offset from the center of its core, finding that it has no apparent
preferential central position relative to the low-mass members.Comment: 44 pages, 13 figures, accepted to Ap
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