## Monday, May 05, 2008 ... //

### Pioneer anomaly: 1/3 due to heat flux

The Pioneer anomaly, the excessive and unexplained 0.87 ± 0.13 nanometers per squared second Sunward acceleration of the Pioneer 10, 11 spacecrafts (which is now reducing the annual distance traveled by the probes by 5,000 km or so), may be caused by an asymmetric heat flux.

Slava Turyshev (JPL, NASA, preprint)
has performed a detailed analysis of the heat flux inside and outside the spacecraft (especially the heat produced by various components of the device).

The predictions of his model seem to agree with the temperatures measured at 100 points within 3 °C. The previously neglected effect can explain 28-36% of the anomaly. Turyshev believes that the probe could have been harmed by interplanetary dust which could have modified the heat flux and the whole anomaly could be explained in this way.

In six months, he could be able to confirm or rule out this hypothesis.

Bonus figure: Czech ice-hockey player Jaromír Jágr's locker. Note that Walter Isaacson's biography of a well-known physicist is given a special place in it. Jágr is already reading the 12th chapter and he is inspired by it. Jágr's Rangers have been eliminated from the play-offs - where they couldn't get for many years before Jágr's era. The NHL won't be - or wouldn't be - the same without Jágr.