scholarly journals Solar System Size Proto-Stellar Sources Embedded in the ρ Oph Dark Cloud

1987 ◽  
Vol 115 ◽  
pp. 71-74
Author(s):  
H. Zinnecker ◽  
A. Chelli ◽  
C. Perrier
Keyword(s):  
Solar System ◽  
Spatial Structure ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
System Size ◽  
Young Stars ◽  
Dark Cloud ◽  
Infrared Observations ◽  
Stellar Sources

High spatial resolution infrared observations (mostly at L, some at K) of several young stars in the ρ Oph dark cloud were obtained with the specklegraph at the ESO 3.6m telescope in Chile in July 1985. Sources included EL29, EL21, EL14 and EL9 (Elias 1978, Table 2), and were all measured in two orthogonal directions, W-E (PA=90°) and N-S (PA=180°). Here we shall present visibility functions for EL29 and EL21 and indicate the spatial structure and dimension of these objects. We refer to Elias (1978, p.468/69) for earlier studies of EL29 and EL21.

scholarly journals High Spatial Resolution Mid-Infrared Observations of Three Seyfert Galaxies

2003 ◽  
Vol 126 (1) ◽  
pp. 143-152 ◽  
Author(s):  
B. T. Soifer ◽  
J. J. Bock ◽  
K. Marsh ◽  
G. Neugebauer ◽  
K. Matthews ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Seyfert Galaxies ◽  
Mid Infrared ◽  
Infrared Observations

scholarly journals Old Structure – Young Stars The Stellar Content of the Centre of the LMC Bar

1999 ◽  
Vol 192 ◽  
pp. 108-111
Author(s):  
P. Linde ◽  
A. Ardeberg ◽  
B. Gustafsson
Keyword(s):  
Image Processing ◽  
Star Formation ◽  
Spatial Resolution ◽  
Chemical Evolution ◽  
High Spatial Resolution ◽  
Young Stars ◽  
Stellar Content ◽  
History Of ◽  
Older Populations

The history of star formation and chemical evolution are studied in the LMC Bar centre with the HST PC and WFC and uvby photometry. Using dedicated image processing, we secured high spatial resolution and photometric quality. We present colour magnitude diagrams (CMDs) from PC and WFC y and b data. The PC provides a CMD close to complete to V = 23.5, the WFC contributes favourable statistics on brighter stars. We find a population of stars seemingly around or younger than 0.2 Gyr comprising around 30% of the total amount of stars. Star formation seems to have decreased 3-0.2 Gyr ago. Older populations are aged 3–9 Gyr. Stars older than 10 Gyr seem rare if not absent. Our CMD morphology and, especially, our uvby metallicity index give [Me/H] close to −0.4, with older stars more and younger stars less metal poor.

Far-infrared observations of W51 with high spatial resolution

1975 ◽  
Vol 196 ◽  
pp. L31 ◽  
Author(s):  
P. M. Harvey ◽  
W. F. Hoffmann ◽  
M. F. Campbell
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Far Infrared ◽  
Infrared Observations

scholarly journals Modeling spatial structure of thermokarst lake fields in permafrost of Western Siberia based on satellite images

2019 ◽  
Vol 19 (1) ◽  
pp. 1-10
Author(s):  
Vladimir Yu. Polishchuk ◽  
Ildar N. Muratov ◽  
Yury M. Polishchuk
Keyword(s):  
Spatial Structure ◽  
Size Distribution ◽  
Spatial Resolution ◽  
Satellite Images ◽  
Western Siberia ◽  
High Spatial Resolution ◽  
The Arctic ◽  
Landsat 8 ◽  
Small Lakes ◽  
Thermokarst Lakes

Deciphering the satellite images of medium and high spatial resolution of the northern territories of Western Siberia has been carried out using geoinformation system ArcGIS 10.3. Images of medium resolution Landsat-8 and high resolution Kanopus-V were used. Kanopus-V images alluded to determine the number and areas of small lakes, which are considered as intensive sources of methane emission into the atmosphere from thermokarst lakes. Data on the spatial characteristics of thermokarst lakes were obtained. Based on the integration of images of medium and high spatial resolution, a synthesized histogram of the distribution of lakes in a wide range of sizes was constructed, taking into account small lakes. The obtained histogram was approximated by a lognormal distribution law by the Pearson criterion with a probability of 0.99. Based on the geo-simulation approach, a new model of the spatial structure of the fields of thermokarst lakes is presented, taking into account the lognormal law of the lake size-distribution. Algorithms for modeling the spatial structure of the fields of thermokarst lakes are described. An example of modeling the field of thermokarst lakes with a lognormal law of their size-distribution is given. The practical applicability of the previously developed model with an exponential distribution of lakes in size, based on data from Landsat images, has been experimentally confirmed. The results can be used to obtain predictions of the dynamics of methane emissions from the thermokarst lakes of the Arctic zone of Northern Eurasia for the coming decades in the context of climate changes.

scholarly journals High Spatial Resolution Mid‐Infrared Observations of Five Seyfert Galaxies

2004 ◽  
Vol 116 (820) ◽  
pp. 493-496 ◽  
Author(s):  
B. T. Soifer ◽  
G. Neugebauer ◽  
K. Matthews ◽  
E. Egami ◽  
L. Armus
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Seyfert Galaxies ◽  
Mid Infrared ◽  
Infrared Observations
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