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Minor bodies of the Solar system (30.11.2016, 15:00)

Опубликовано: 24/11/2016

Date: 30.11 2016., 15:00

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Speaker: Andrey K. Murtazov, Institute of Astrophysics of the Academy of Sciences of the Republic of Tajikistan.

Title: Methodic support for near space optical monitoring expert systems. Doctoral dissertation.

Abstract:

The system analysis of near space contamination optical monitoring problem is done.Organization of data bank for scientific assessments of satellite identification using its optical monitoring results is presented.
The databank includes: method of satellite’ covers and atmosphereless bodies optical properties physical simulation; satellite’ scattering fields modelling data and its comparative analyses with optical monitoring data using recognition criterions.
Investigations made possible to solve the important problem – identification of satellites by using its optical monitoring data.
They are presented: the methodic of hazard meteoroids in meteor showers wide-angle CCD-monitoring; assessments of the hazardous Perseids flux density during the long-time period;
model of the risk of meteoroid collision with spacecraft in near Earth space; the methodic of assessing the average risk of collision between bright meteoroids and spacecraft with different parameters of its orbits.

Speaker: Roshchina E.A., Izmailov I.S., Khovrichev M.Yu.  Main (Pulkovo) Astronomical Observatory of RAS, Saint Petersburg, Russia

Title: CCD observations of solar system bodies at Pulkovo.

Abstract:

The observations of asteroids, planets and their natural satellites provide the material necessary for the construction and improvement of the theory of celestial bodies motion. Improvement of theories is significant not only for the connection between stellar and dynamic reference systems, but also to provide more accurate ephemeris for space missions. All the accumulated set of observations since the celestial body discovery to the present time is used to construct a theory of the motion of planets and satellites.

At present time the amount of astrometric observations of solar system bodies is huge. But most of the observations were made with systems designed for the search of new objects. They are characterized by the scale of a few seconds per pixel and have a low accuracy (200 mas and worse) and significant systematic errors. This complicates usage of these data to development of motion theories.

Meantime, in the Gaia epoch the one of important aims of positional astronomy is a progress in the construction of reference frame in the optical range. The use of instruments, that provide the ground-based observations with accuracy about 10 - 50 mas, allows us to realize the potential of the Gaia catalogue to study the dynamics of the Solar system. The astrometric observations of objects that interesting for dynamics study (the satellites of the major planets, near-Earth asteroids, asteroids that are in unstable resonance) are especially important now and in the future. Laboratory of astrometry and stellar astronomy of the Pulkovo Observatory provides the opportunities for these observations.

Currently, the observations of small bodies of the solar system are carried out using three telescopes:

26-inch refractor (D/F=650мм/10413мм, CCD FLI Pro Line 09000, FOV 12'x12', scale 0.238 arcsec/px),

Normal astrograph (D/F=330мм/3467 мм, CCD SBIG ST-L-11K , FOV=35'x23', scale 0.533 arcsec/pix),

1-m telescope «SATURN» (D/F =1000 мм/4000 мм, CCD S2C , FOV=14'x14', scale 0.82 arcsec/px).

Image processing is performed using IZMCCD software package (http://izmccd.puldb.ru/index2.htm). Shapelet decomposition is used to centroiding stellar images in the CCD-frames filmed with "Saturn"telescope and the Moffat's profile - for observations with other telescopes.

We present the results of observations of selected asteroids, main satellites of Saturn, Uranus and Galilean satellites of Jupiter, and the comparison of observations with theory. The internal accuracy of the positions is estimated using the dispersion of the ephemeris and observations differences and is about 5 - 65 mas for 26-refractor and 30 - 100 mas for other telescopes. It depends on the object and conditions of observation. The observation results are available via Pulkovo astrometric data base www.puldb.ru.