Application of the terminator tether™ Electrodynamic drag technology to the Deorbit of constellation spacecraft

34th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit

Volumn , Issue , 1998, Pages

  Forward, Robert L ^a   Hoyt, Robert P ^a   Uphoff, Chauncey ^b  

^a Tethers Unlimited Inc   (United States)

^b Fortune Eight Aerospace Industries   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

COMMUNICATION SATELLITES; DRAG; ELECTRODYNAMICS; ORBITS; PROPULSION; ROCKETS; SATELLITES; SPACE FLIGHT; SPACECRAFT;

CONSTELLATION ORBITS; CONSTELLATION SATELLITES; CONSTELLATION SPACECRAFT; CROSS SECTIONAL AREA; ELECTRO-DYNAMIC TETHER; LIGHTWEIGHT SYSTEMS; LOW COST AND RELIABLE; ORDERS OF MAGNITUDE;

TETHERLINES;

EID: 34548152975     PISSN: None     EISSN: None     Source Type: Conference Proceeding    
DOI: None     Document Type: Conference Paper

References (19)

1. Loftus, JP., JLoftus@ems.jsc.nasa.gov, personal communication via email Monday 10 June 199615:50:10.
2. Forward, R.L., “Electrodynamic Drag Terminator Tether'“, Appendix K, in Final Report on NAS8-40690,10 July 1996.
3. Office of Science and Technology Policy: 1995, Interagency Report on Orbital Debris 1995, The National Science and Technology Council
4. NASA Safety Standard: Guidelines and Assessment Procedures for Limiting Orbital Debris. (NSS 1740.14, August 95).
5. Space News, March 31-April 6, 1997, p 16.
6. Space News, Aug 4-10, 1997, p 30.
7. Estes, R., restes@mars.harvard.edu, personal communication via email Friday 31 May 1996 10:39:16.
8. Loftus, JP. JLoftus@ems.jsc.nasa.gov, personal communication via email Wednesday 19 June 1996 08:20:39.
9. Lorenzini, E., personal communication, 13 March 1997.
10. Johnson, L., “Propulsive Small Expendable Deployer System Mission (ProSEDS)”, OAST Advanced Propulsion Workshop, JPL, Pasadena, CA, 20-22 May 1997.
11. Gilchrist, B., personal communication, 12 May 1997.
12. Sanmartin, J.R., Martinez-Sanchez, M., Ahedo, E., “Bare Wire Anodes for Electrodynamic Tethers,” J. Propulsion and Power, 7(3), pp. 353-360,1993
13. Hoyt, RP., Forward, R.L., “Electrodynamic Hoytethers for ISS and LEO Spacecraft”, Appendix E of High Strength-To-Weight Tapered Hoytether for LEO to GEO Payload Transport, Final Report on NASA Contract NAS8-40690,10 July 1996.
14. Note that in Eq. 9, the correct velocity vector to use is the relative velocity vM=vo~®E'r cosA, between the orbiting spacecraft and the geomagnetic field, since the geomagnetic field rotates with the Earth at the rate of ooE=27t rad/day. For an equatorial orbit at an altitude of 1000 km, the velocity of the geomagnetic field is 0.536 km/s or only 7% of the orbital velocity of 7350 m/s. For nonequatorial orbits the difference is even smaller. We will ignore this small difference to keep the equations manageable.
15. By a geometric coincidence, the transverse magnetic field Bj and therefore voltage V given by Eq. 11 are both essentially constant over the entire orbit, despite the fact that the horizontal magnetic field varies from a maximum at the magnetic equator Bff(A=0) to a smaller value of Bff(A=A,) at the northernmost portion of an orbit with geomagnetic inclination A,. The variation in horizontal magnetic field strength Bfj(A) with latitude A on the Earth and the variation in the angle at which the velocity vector crosses BN, combine to produce a constant transverse magnetic field BT=Bff(A=X) over the entire orbit.
16. Jaccia, L.G., “Thermospheric Temperature, Density, and Composition: New Model,” SAO Special Report 375, Mar. 1977.
17. The results for orbits with i>78.5 assume that the tether system can carry current in both directions; if the tether system is designed to carry current in one direction only, the deorbit times will be roughly twice as long, due to portions of the day when the orbit is retrograde to the magnetic dipole.
18. Penzo, P.A., and Ammann, P.W., eds., Tethers In Space Handbook, 2nd Edition, NASA/OSF, 1989, p. 168-9.
19. Hoyt, RP., Forward, R.L., “The Hoytether: A Failsafe Multiline Space Tether Structure,” Tether Technical interchange Meeting, Huntsville, AL, Sept 9-10, 1997.