Conference on

The Pioneer Anomaly

- Observations, Attempts at Explanation, Further Exploration -

ZARM, Bremen 18. - 19. May 2004


Time and Place



Schedule + Talks








Recently, the observation of an anomalous behaviour of massive bodies in weak gravitational fields attracted some interest. The most prominent example is the Pioneer anomaly. Another example concerns the rotation curves of galaxies. On the phenomenological side this behaviour has been related, e.g., on a phenomenological level, to a theory with a modified Newtonian dynamics (MOND theory) or, on a more fundamental level, to a bi-metric theory. Also its relation to dark matter and dark energy has been discussed.
In this meeting the status of this area and possible approaches for further exploration and clarification will be discussed.

Time and Place:

Begin: Tuesday, 18. May 2004 at 9:45
End: Wednesday, 19. May 2004,

The lectures will be held at
Center for Applied Space Technology and Microgravity (ZARM)
University Bremen
Am Fallturm
28359 Bremen


Lämmerzahl, Claus

University of Bremen
Am Fallturm
28359 Bremen

Phone: +49 (0)421 - 218 - 8687
Fax: +49 (0)421 - 218 - 2521

Conference Fees:

We will take conference fees of 30 Euro. We are able to accept credit cards.

These fees cover lunchs, coffe breaks and the conference dinner.

Schedule and Talks:

Monday 17.5.


approx. 18:00

Short visit of the City of Bremen



Dinner for those who already arrived

Tuesday 18.5.


09:45 - 10:00



Overview lectures


10:00 - 10:45


The Pioneer effect: History and overview


10:45 - 11:45


Finding the origin of the Pioneer anomaly


11:45 - 12:30


Overview: proposed mechanisms to explain the Pioneer anomaly and missions to test it


12:30 - 13:30


Attempts at explanations


13:30 - 14:15


Attempts at explanations within standard physics


14:15 - 14:45


Pioneer anomaly, braneworlds and scalar fields


14:45 - 15:15


The Pioneer anomaly is just a cosmological Berry phase


15:15 - 15:45


Pioneer acceleration, light acceleration and time acceleration


15:45 - 16:15

coffee break

proposed missions


16:15 -17:00


A proposed mission to verify the Pioneer anomaly


17:00 -17:30


ENIGMA - a mission exploring the Pioneer effect


17:30 - 18:00


Testing for the Pioneer anomaly on a Pluto-exploration mission


18:00 - 18:30


Dark Matter Explorer Mission


18:30 - 19:00

Ni / Lämmerzahl

Deep space mission ASTROD: MOND and the Pioneer anomaly



Conference Dinner

Wednesday 19.5.
Detection of forces


09:00 - 09:45


Testing Newton force law at short and long distances


09:45 - 10:05


Atom interferometer based inertial sensors for long term missions?


10:05 - 10:25


Atomic interferometry with coherent ensembles


10:25 - 11:00

Coffe break


11:00 - 11:30


Sagnac Revisited: A Spacetime Perspective


11:30 - 12:00


The Cosmological Constant and Non-Newtonian Gravity


12:00 - 12:30


ESA Study on Gravity Control and its Influence on Space Propulsion


12:30 - 13:30


Other missions


13:30 - 14:00


The LATOR mission


14:00 - 14:10


Fast solar system escape missions using non-futuristic solar sails


14:10 - 14:40


Cassini measurement of gravitational time delay


14:40 - 15:15

Drop-tower tour


15:15 - 15:45

Coffe break

Fundamental physics at NASA and ESA


15:45 - 16:15


NASA Fundamental Physics


16:15 - 16:45

de Matos

Perspectives in Fundamental Physics in Space


16:45 - 16:55


ESA call: cosmic vision 2015


16:55 - 18:30





Dinner and end of workshop

(subject to changes)


Angonin, Marie-Christine (Paris, France)
Bertolami, Orfeu (Lisboa, Portugal)
Blome, Hansjoachim (FH Aachen)
Bordé, Christian (Institute Poincarée, Villetaneuse, France)
Boyer, Philippe (Orsay, France)
Brihaye, Yves (Univ. Mons, Belgium)
Dachwald, Bernd (DLR, Köln, Germany)
Dittus, Hansjörg (ZARM, Univ. Bremen, Germany)
Duif, Chris P. (Delft Univ., The Netherlands)
Genet, Frank (Paris, France)
Hartmann, Betti (International Univ. Bremen, Germany)
Hehl, Friedrich W. (Univ. Köln, Germany)
Johann, Ulrich (Astrium, Friedrichshafen, Germany)
Kent, Barry (Rutherford Appleton Laboratory, Chilton, UK)
Kleihaus, Burkhard (Univ. Oldernburg, Germany)
Kunz, Jutta (Univ. Oldernburg, Germany)
Lämmerzahl, Claus (ZARM, Univ. Bremen, Germany)
Mashhoon, Bahram (University of Missouri-Columbia, USA)
Matos, Clovis de (ESA, Paris, France)
Mehls, Carsten (ZARM, Univ. Bremen, Germany)
Nieto, Michael M. (Los Alamos, USA)
Páramos, Jorge (Lisboa, Portugal)
Penanen, Konstantin (JPL, USA)
Peters, Achim (Humboldt-Univ. Berlin, Germany)
Perlick, Volker (TU Berlin, Germany)
Ranada, Antonio F. (Univ. Madrid, Spain)
Rasel, Ernst M. (Institute for Quantum Optics, Univ. Hannover, Germany)
Rathke, Andreas (ESA, Noordvijk, The Netherlands)
Reinhard, Rüdeger (ESA, Noordvijk, The Netehrlands)
Reynaud, Serge (Univ. Paris VI, France)

Rosales, Jose Luis ( Madrid, Spain)
Schäfer, Gerhard (Univ. Jena, Germany)
Schalinski, Cornelius (OHB Systeme, Bremen, Germany)

Scheithauer, Silvia (ZARM, Univ. Bremen, Germany)
Schleicher, Alexander (ZARM, Univ. Bremen, Germany)
Seboldt, Wolfgang (DLR, Köln, Germany)
Selig, Hanns (ZARM, Univ.
Bremen, Germany)
Theil, Stephan (ZARM, Univ.
Bremen, Germany)
Touboul, Pierre (ONERA, Paris, France)
Tucker, Robin (Univ Lancaster, UK)
Turyshev, Slava G. (JPL, USA)



There are good connections between Bremen airport and the international airports Frankfurt and Amsterdam.

Travel from the airport to Hotel Horner Eiche: Take tram No 6 (direction ''University'') to main train station, change there to tram No 4 (direction ''Borgfeld''), get off the tram at stop ''Kopernikusstrasse'' (15 stops after main station), then 2 minutes by foot to the hotel. The tram ticket costs 1.95 Euro. [Last tram at 23:44.]

From main station to hotel: take tram No 4 (direction ''Borgfeld'') and get off the tram at stop ''Kopernikusstrasse'' (15th stop), then 2 minutes by foot to the hotel. The tram ticket costs 1.95 Euro. [Last tram at 0:30.]

Web page of Hotel Horner Eiche.

Here is the travel information about how to arrive at ZARM.

From Hotel Horner Eiche there is a public bus to ZARM (bus No 32). The bus stop is in front of the hotel. The single fare is 80 Euro-cents.

Here is a map showing the location of the Hotel Horner Eiche and the Bremen Drop Tower (ZARM). This is in the north of Bremen. The distance between the Hotel and the ZARM is about 2 km.




This meeting is sponsored by EADS Astrium and ZARM.



On the observation

  1. J.D. Anderson, P.A. Laing, E.L. Lau, A.S. Liu, M.M. Nieto, and S.G. Turyshev: Study of the anomalous acceleration of Pioneer 10 and 11, Phys. Rev. D 65, 082004 (2002).
  2. J.D. Anderson, P.A. Laing, E.L. Lau, A.S. Liu, M.M. Nieto, and S.G. Turyshev: Indication, from Pioneer 10/11, Galileo, and Ulysses data, of an apparent anomalous, weak, long-range acceleration, Phys. Rev. Lett. 81, 2858 (1998). [Comment by J.I. Katz: Phys. Rev. Lett. 83, 1892 (1999); Reply: Phys. Rev. Lett. 83, 1893 (1999)].

Attempts at explanations within standard physics

  1. A.F. Ranada: The Pioneer anomaly as acceleration of the clocks, gr-qc/0410084.
  2. Y.G. Yi: On the indication from Pioneer 10/11 data of an apparent anomalous, weak, long-range acceleration, Gen. Rel. Grav. 36, 875 (2004).
  3. D. Bini, C. Cherubini, and B. Mashhoon: Vacuum C-Metric and the Gravitational Stark Effect, Phys. Rev. D 70, 044020 (2004) [gr-qc/0401071].
  4. J.L. Rosales: The Pioneer's Anomalous Doppler Drift as a Berry Phase, gr-qc/0401014.
  5. J.D. Anderson and B. Mashhoon: Pioneer Anomaly and the Helicity-Rotation Coupling, Phys. Lett. A 315, 199 (2003).
  6. M.M. Nieto and S.G. Turyshev: Finding rhe origin of the Pioneer anomaly, gr-qc/0308017.
  7. L.K. Scheffer: Conventional forces can explain the anomalous acceleration of Pioneer 10, Phys. Rev. D 67, 084021 (2003).
  8. J.-L. Rosales, and J.-L. Sanchez--Gomez: The 'Pioneer effect' as a manifestation of the cosmic expansion in the solar system, gr-qc/9810085.
    J.L. Rosales: The Pioneer's acceleration anomaly and Hubble's constant, gr-qc/0212019.
  9. J.D. Anderson, E.L. Lau, S.G. Turyshev, et al.: Search for a standard explanation of the pioneer anomaly, Mod. Phys. Lett. A 17, 875 (2002).
  10. L. Licht: The Expanding Universe, Planetary Motion and the Pioneer 10/11 Anomaly, gr-qc/0102103.


  1. J.D. Bekenstein: Relativistic gravitation theory for the MOND paradigm, astro-ph/0403694.
  2. M. Milgrom: MOND - theoretical aspects, New Astr. Rev. 46, 741 (2002).
  3. D. Ostvang: An explanation of the 'Pioneer effect' based on quasi-metric relativity, Class. Quantum Grav. 19, 4131 (2002).

Attempts at explanations with ''new physics''

  1. K. Krogh: Origin of the Blueshift in Signals from Pioneer 10 and 11, astro-ph/0409615
  2. R. Foot: Implications of the DAMA and CRESST experiments for mirror matter-type dark matter, Phys. Rev. D 69, 036001 (2004).
  3. K. Trencevski: Hubble red shift and the anomalous acceleration of Pioneer 10 and 11, gr-qc/0402024
  4. J.W. Moffat: Modified Gravitational Theory and the Pioneer 10 and 11 Spacecraft Anomalous Acceleration, gr-qc/0405076.
  5. A.F. Ranada: On the Pioneer acceleration as light acceleration, gr-qc/0403013.
  6. A.F. Ranada: The light speed and the interplay of the quantum vacuum, the gravitation of all the universe and the fourth Heisenberg relation, Int. J. Mod. Phys. D 12, 1755 (2003).
  7. M. Cadoni: An Einstein-like theory of gravity with a non-Newtonian weak-field limit, gr-qc/0312054.
  8. O. Bertolami, J. Páramos: The Pioneer anomaly in a bimetric theory of gravity on the brane, gr-qc/0310101.
  9. A.F. Ranada: The Pioneer riddle, the quantum vacuum and the acceleration of light, Europhys. Lett. 63, 653 (2002).
  10. M.A. Ivanov: Non-Dopplerian cosmological redshift parameters in a model of graviton-dusty universe, Class. Quantum Grav. 19, 1351 (2002).
  11. J.Q. Shen: Gravitational analogues, geometric effects and gravitomagnetic charge,Gen. Rel. Grav. 34, 1423 (2002).
  12. M.A. Ivanov: Possible manifestations of the graviton background, Gen. Rel. Grav. 33,: 479 (2001).
  13. R. Foot, R. R. Volkas: A mirror world explanation for the Pioneer spacecraft anomalies?, Phys.Lett. B 517, 13 (2001).
  14. E. Schmutzer: Distribution of Dark Matter around a Central Body, Pioneer Effect and Fifth Force, Astronom. Nachr. 322, 93 (2001).
  15. Dag Østvang: An Explanation of the "Pioneer Effect" based on Quasi-Metric Relativity, Class.Quant.Grav. 19, 4131 (2002).
  16. G. Modanese: Effect of a scale-dependent cosmological term on the motion of small test particles in a Schwarzschild background, Nucl.Phys. B 556, 397 (1999).

Proposals for new missions

  1. J.D. Anderson, M.M. Nieto, M.M. and S.G. Turyshev: A Mission to test the Pioneer Anomaly, Int. J. Mod. Phys. D 11, 1545 (2002).
  2. J.L. Rosales: The Pioneer anomalous acceleration: a measurement of the cosmological constant at the scale of the solar system, gr-qc/0307042.
  3. O.,Bertolami and M. Tajmar: Gravity Control and Possible Influence on Space Propulsion: A Scientific Study, ESA CR(P)4365.Lett. A 315, 199 (2003).
  4. O. Bertolami and M. Tajmar: Hypothetical Gravity Control and Implications for Spacecraft Propulsion, gr-qc/0207123

Some pictures from Bremen

ZARM with Drop tower
(146 m)




City Hall



Market square with "Roland"

residential area

downtown Bremen

The Bremen flag.

This flag has its origin in the middle ages. The red and white stripes symbolize the liberty of the citizens of Bremen. It is told that the American flag is modeled on this flag.

areal view


Bremen town musicians

Windmill in downtown Bremen



Typical countryside architecture

Some more information on Bremen can be found on


Welcome to Bremen!