Although the Bullet Cluster (1E 0657-558) provides a strong evidence to the existence of a form of dark matter, our today knowledge still lacks direct empirical data on the dynamics of space-time (gravity) at very low curvatures. Perhaps it is highly appreciated to propose and perform experiments - based on current/near future technology- to observe the nature at very low gravitational acceleration.

We present two such proposals. We consider the AQUAL model, a promising model altering the dynamics of the space-time at low gravity. We report that the AQUAL model enhances the gravity at the sub-micrometer ranges around the gravitational saddle points in a way that so far had been unnoticed. This enhancement can be measured by implementing today's micrometer gravity tests within the gravitational saddle points of the solar system. We also notice that a general relativistic extension of the AQUAL model enhances the precession of a gyroscope embedded in the gravitational saddle point of the Sun-Jupiter system, and the near future technology can detect the enhancement.

IPM Larak Building, School of Astronomy