Date: 28.03.2018., 15:00

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1. Report by Dr. Kovalenko I.D. (IKI, INASAN)

“Problem of launch of two spacecraft into the vicinity of the L1 point of the Sun-Earth system”

 A trajectory scenario is designed to transfer two spacecraft into the vicinity of the Lagrangian point L1 of the Earth-Sun system. The scenario includes a lunar gravity assist, aimed at the achievement of a suitable relative positioning of two spacecraft. The problem is relevant to the future mission SODA (System of Observation of Daytime Asteroids), a project proposed by INASAN for detecting dangerous asteroids approaching the Earth from the Sun. Currently, such asteroids cannot be observed by ground-based or low-Earth telescopes. Configuration of two spacecraft in L1 orbits with different phases might significantly improve an accuracy of determination of trajectory and entry point into the atmosphere.

2. Repot by Scherbina M.P. (SAI MSU)

“The research of the spectral characteristics and the assessment of the composition of the substance of asteroids, including approaching the Earth” (on materials of qualification work)”

 Asteroids are one of the most ancient objects in the Solar system, whose composition has minimally changed since its formation. However, only for a relatively small number of them a spectral class was determined. The question of the composition and distribution of asteroids of different classes remains open, while based on these data it is possible to confirm or disprove a particular cosmological model, to replenish the database of asteroids approaching the Earth.

Using observational data obtained at the Peak Terskol Observatory, the Crimean Laboratory of the SAI of Moscow State University and the Sanglok Observatory, the reflection spectra were processed and simulated.

For each of the asteroids under consideration, a qualitative (using D. Tolen’s spectral classification) and quantitative interpretations (using a MatLab-based program developed for this purpose) of chemical and mineral composition were performed, the relative content of basic minerals in the substance was determined so as a spectral class. In addition, meteorite analogs were identified.

Spectrophotometric asteroids of close primitive types allowed registering spectral signs of simultaneous sublimation activity (the presence of maxima in the reflection spectra at ~ 0.35–0.60 µm, ~ 0.55–0.75 µm) in some of them, which can be associated with their small heliocentric distances and, accordingly, with high surface insolation. During 2017, spectrophotometric and photometric observations of the asteroid (704) Interamnia (a primitive-type asteroid of Main Belt) were carried out at three observatories, the data confirmed periodic sublimation activity near the perihelion, first discovered in 2012. Sublimation activity indicates the formation of such bodies in the early Solar system near the frost line