Solar Conjunctions ESA Spacecraft Mars Express MEX 5

Solar Conjunctions: ESA Spacecraft Mars Express (MEX) 5 conjunctions Current State Conjunction № 1 18 Aug 2004 – 22 Oct 2004 Conjunction № 2 08 Oct 2006 – 22 Nov 2006 Conjunction № 3 01 Nov 2008 – 15 Jan 2009 Conjunction № 4 26 Dec 2010 – 27 Mar 2011 Результаты представлены на этой конференции Conjunction № 5 04 Mar 2013 – 10 Apr 2013 Обработка Conjunction № 6 May 2015 Возможны эксперименты Rosetta (ROS) Результаты публиковались в течение 2010 -2014 2 conjunctions Conjunction № 1 15 Mar 2006 – 04 May 2006 Результаты опубликованы в 2010 Conjunction № 3 03 Oct 2010 – 31 Oct 2010 Результаты представлены на этой конференции Conjunction № 4 February 2015 Возможны эксперименты Venus Express (VEX) Conjunction № 1 1 conjunction 08 Oct 2006 – 05 Dec 2006 Результаты представлены на конференции 2013 3

ROSETTA 2010: Conjunction Geometry MARS EXPRESS 2011: Conjunction Geometry View from Earth: Ecliptic Coordinates 4

Radio-Sounding Observations 2010 -2011 • Frequencies: S-band (2. 3 GHz), X-band (8. 4 GHz) • Tracking stations: DSN: Madrid (DSS 63), Goldstone (DSS 14) ESTRACK: New Norcia (DSS 32) • Low solar activity • Frequency fluctuations: temporal spectra (power law index F), RMS radial profile: F = Bi(R / RS)-b • Range delay measurements temporal spectra quasi-periodic fluctuations 6

Results of theoretic analysis In fact thanks to the transformation of the X-band signal into S-band signal with the use the spacecraft transponder with low coefficient this scheme provides one-way sounding of the solar corona by the S-band signals with a frequency stability of the hydrogen standard 7

Радиальные зависимости σf и спектрального индекса αf ROSETTA 2010 σ fi = DOY 284 DOY 297 -β B fi (R/R S ) fi i = s, x, d ROSETTA Ingress + Egress s: βfs = -1. 828 Bfs = 17. 119 x: βfx = -1. 764 Bfx = 6. 473 d: βfd = -1. 808 Bfd = 15. 222 Kolmogorov v a l u e: 2 / 3 MARS EXPRESS Ingress s: βfs = -1. 986 Bfs = 29. 315 x: βfx = -1. 957 Bfx = 14. 430 d: βfd = -2. 083 Bfd = 36. 809 Egress s: βfs = -1. 607 Bfs = 7. 895 x: βfx = -1. 612 Bfx = 3. 732 d: βfd = -1. 642 Bfd = 8. 084 9

Enhanced frequency fluctuations at coronal sounding during solar conjunctions of ROS in 2010 and MEX in 2010/2011 № R/RS Limb (tmax n-tmax 1) σFmax / calc. days σFnom Year DOY Date 1 ROS 2010 284 11 Oct 10: 22: 20 13. 53 East 0 0 4. 61 2 ROS 2010 297 04 Oct 13: 00: 40 21. 88 West 13. 11 (~0. 5 Tsin) 13. 13 2. 86 3 MEX 2010 365 31 Dec 06: 56: 23 30. 78 East 80. 86 (~3 Tsin) 80. 54 11. 32 4 MEX 2011 028 28 Jan 14: 52: 18 07. 15 East 109. 18 (~4 Tsin) 108. 32 3. 65 5 MEX 2011 041 10 Feb 18: 06: 27 06. 41 West 122. 36 (~4. 5 Tsin) 121. 82 4. 32 6 MEX 2011 068 09 Mar 05: 49: 04 26. 40 West 148. 81 (~5. 5 Tsin) 148. 5 11. 03 event UTmax (tmax n-tmax 1) meas. days S/C It is follows from Table that the enhanced frequency fluctuations were observed at time shifts relatively to the first conjunction (DOY 284, east side) proportional to n×T or to m× 0. 5 T , where T is sinodic period of the Sun rotation (T=27 days) in this case the enhancement of the frequency fluctuations is connected with the same region of the Sun surface 18