Moscow, IKI, October 10-14, 2011Moscow, IKI, October 10-14, 2011

PHOTOMETRIC AND RADIOMETRIC PHOTOMETRIC AND RADIOMETRIC PROPERTIES OF PHOBOS PROPERTIES OF PHOBOS REGOLITH FROM DATA GATHERED REGOLITH FROM DATA GATHERED BY THE PHOBOS MISSIONBY THE PHOBOS MISSION

L.V. Ksanfomality, L.V. Ksanfomality, Space research institute of the RAS Space research institute of the RAS

Moscow Moscow

The second Moscow Solar system symposiumThe second Moscow Solar system symposium

KRFM KRFM PHOBOS-2PHOBOS-2

19891989

March 25, 1989March 25, 1989

The KRFM instrument operated in 9 photometric channels (325, 328, 346, 363, 410, 445, 488, 550 and 600 nm) and 6 radiometric channels (4.8-6.4, 6.1-7.8, 7.2-9.3, 9.2-13.6, 14.3-15.9, and 16.5- 49 mcm)

The geometric albedo ρ (λn) = Ntm βF / Φ, where Φ is photometric function including two quantities, phase function θ(α) and function f of zenith distances of the Sun zs and of the spacecraft za:

Φ (α, zs, za) = f (zs, za).

The approach of Lumme for large particles (2 πr/ λ >>1) was used:

θ(α) = (1 – Г) θ1(α) + Г θм(α),

With θ1(α) – for single and θм(α) for multiple scattering.

All the highly degraded craters along track 1 possess All the highly degraded craters along track 1 possess albedo from 4.8 to 6.8%, at wavelengths in the range albedo from 4.8 to 6.8%, at wavelengths in the range 490-600 nm and from 3.1 to 4.0% at wavelengths in the 490-600 nm and from 3.1 to 4.0% at wavelengths in the range 330-410 nm. Conversely, the comparatively range 330-410 nm. Conversely, the comparatively young craters have reduced albedo, for example, both young craters have reduced albedo, for example, both the crater at 187°W and the neighboring crater at the crater at 187°W and the neighboring crater at 197°W. Their albedo is lower, from 2.8 to 3.2% in the 197°W. Their albedo is lower, from 2.8 to 3.2% in the short-wave channel, and from 4.1 to 5.2% in the long-short-wave channel, and from 4.1 to 5.2% in the long-wave channel. wave channel.

In darker region along track 2, the albedo in the range In darker region along track 2, the albedo in the range 550-600 nm rapidly falls from 5.4 to 4.1%. In the short-550-600 nm rapidly falls from 5.4 to 4.1%. In the short-waves (330-410 nm), the drop in albedo is less waves (330-410 nm), the drop in albedo is less noticeable, from 3.2-3.5 to 2.9-3.0%. The minimum near noticeable, from 3.2-3.5 to 2.9-3.0%. The minimum near 232° W represents a large, well-preserved crater with 232° W represents a large, well-preserved crater with center at 25° N, 245° W. The albedo drops in the range center at 25° N, 245° W. The albedo drops in the range 410-600 nm as approaching this crater, which is 410-600 nm as approaching this crater, which is reasonable to associate with ejecta from the crater.reasonable to associate with ejecta from the crater.

Some publications of 1989 – 1997Some publications of 1989 – 1997

Ksanfomality L.V., Moroz V.I. Spectral reflectivity of the Phobos regolith. // Icarus, 1995, v.117, pp.383-401.Moroz V.I., E.V.Petrova, L.V.Ksanfomality. Spectrophotometry of Mars in the KRFM experiment of the PHOBOS mission: some properties of the particles of atmospheric aerosols and the surface // Planet. Space Sci., 1993, v.41, N8, pp.569-585.Kuhrt E., B.Giese, H.U.Keller, L.V.Ksanfomality. Interpretation of the KRFM-Infrared measurements of Phobos. // Icarus, 1992, v. 96, pp.213-218.Ksanfomality L.V., S.Murchie., D.Britt, T.Duxbury, P.Fisher, N.Goroshkova, J.Head, E.Kuhrt, V.Moroz, B.Murray, G.Nikitin, E.Petrova, C.Pieters, A.Soufflot, A.Zharkov, B.Zhukov. // Phobos: spectrophotometry between 0.3 and 0.6 mcm and IR-radiometry // Planet. Space Sci., 1991, v.39, N1/2, pp.311-326.Ксанфомалити Л.В. Фотометрические свойства реголита Фобоса по данным миссии ФОБОС // Астрономич. Вестн., 1991, т.25, N6, с.650-676.Kuhrt E., B.Giese. A thermal model of the Martian satellites. // Icarus, 1989, v. 81, pp. 102-112. Ксанфомалити Л.В., Петрова Е.В., Хартманн У.К. Неоднородность реголита Фобоса по степени зрелости // Астрономический вестник, 1997. Т.31, № 5, с. 422-426.

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