Il Nuovo Cimento C

, Volume 15, Issue 6, pp 1193–1198 | Cite as

Doppler experiments with Cassini radio system

  • G. Comoretto
  • B. Bertotti
  • L. Iess
  • R. Ambrosini


The proposedK a band link on the Cassini orbiter can be used for very accurate Doppler tracking. A two-wayK a band coherent link, near opposition, or more complex schemes involving theX-band link also, can virtually eliminate the noise due to interplanetary plasma, giving an accuracy Δf/f better than 10-15 for time scales of (103 ÷ 104) s. To achieve this accuracy, the other error sources, mainly the tropospheric delay and the clock stability, must be accurately controlled. This sensitivity will allow for the first time for a search for gravitational waves of reasonable amplitude.


04.80 Experimental tests of general relativity 


95.55 Astronomical and space-research instrumentation 


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Copyright information

© Società Italiana di Fisica 1992

Authors and Affiliations

  • G. Comoretto
    • 1
  • B. Bertotti
    • 2
  • L. Iess
    • 3
  • R. Ambrosini
    • 4
  1. 1.Osservatorio Astrofisico di ArcetriFirenzeItalia
  2. 2.Dipartimento di Fisica Nucleare e Teorica dell’UniversitàPaviaItalia
  3. 3.Istituto di Fisica dello Spazio Interplanetario del CNRFrascatiItalia
  4. 4.Istituto di Radioastronomia del CNRBolognaItalia

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