HomeESA spacecraft may help unravel cosmic mystery
When Europe's comet chaser Rosetta swings by Earth tomorrow for a critical gravity assist, tracking data will be collected to precisely measure the satellite's change in orbital energy. The results could help unravel a cosmic mystery that has stumped scientists for two decades.
Since 1990, scientists and mission controllers at ESA and NASA have noticed that their spacecraft sometimes experience a strange variation in the amount of orbital energy they exchange with Earth during planetary swingbys. The unexplained variation is noticed as a tiny difference in speed gained or lost during the swingby when comparing that predicted by fundamental physics and that actually measured after the event.
Full article in ESA web portal -- Daniel
4 comments | "ESA spacecraft may help unravel cosmic mystery"
02-07-2010 • 17:56:05
How Often do the Ground Station is used for other matters than tacking Spacecraft.
13-11-2009 • 07:34:23
In my previous posting, I made a typo. "The empirical formula found by Mbelek et al..." should read ""The empirical formula found by Anderson et al..."
13-11-2009 • 06:39:33
The problem is more complex than that. Mbelek's paper is known also to the control team at the space agency and is not considered to provide the conclusive answer to the "flyby anomaly mystery". Fact is that The empirical formula found by Mbelek et al predicts a residual acceleration in at least one case where in reality none could be observed.
The case should be considered "still open".
12-11-2009 • 17:54:43
I believe there is a good case that the mystery is already solved: Jean Paul Mbelek of Service d'Astrophysique has shown that the formula Anderson et al found empirically is obtained by considering "the SR time dilation, the SR transverse Doppler shift and the addition of velocities (to account for the Earth’s rotation)" (citation from the e-print at http://arxiv.org/abs/0809.1888). It will be interesting to see if something new is learnt from this last Rosetta Earth swingby, now only some 14 hours away...