Thursday, October 04, 2007

More on the Pioneer Anomaly

Here's the abstract from a new preprint: Physics Engineering in the Study of the Pioneer Anomaly
The Pioneer 10/11 spacecraft yielded the most precise navigation in deep space to date. However, their radio-metric tracking data received from the distances between 20--70 astronomical units from the Sun has consistently indicated the presence of a small, anomalous, Doppler frequency drift. The drift is a blue frequency shift that can be interpreted as a sunward acceleration of a_P = (8.74 +/- 1.33) x 10^{-10} m/s^2 for each particular spacecraft. This signal has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained.
Recently new Pioneer 10 and 11 radio-metric Doppler and flight telemetry data became available. The newly available Doppler data set is significantly enlarged when compared to the data used in previous investigations and is expected to be the primary source for the investigation of the anomaly. In addition, the flight telemetry files, original project documentation, and newly developed software tools are now used to reconstruct the engineering history of both spacecraft. With the help of this information, a thermal model of the Pioneer vehicles is being developed to study possible contribution of thermal recoil force acting on the two spacecraft. The ultimate goal of these physics engineering efforts is to evaluate the effect of on-board systems on the spacecrafts' trajectories.

Here's a previous post on the Pioneer Anomaly.

30 Rock

I haven't actually watched this show, but it's having a season premier this week. As I understand it, Alec Baldwin does a good job playing Jack, a crazy network executive in the show. There's a review in the New York Times Sophomore Jitters and Seinfeld Vision :
Jack has decided to increase advertising revenues by digitally inserting Mr. Seinfeld into NBC shows like “Law & Order” and “Deal or No Deal.” Jack calls his computer-generated fakery “SeinfeldVision.” The counterfeited comedian shows up at Rockefeller Center to complain, and that’s when the show goes a little wobbly: Mr. Seinfeld is strangely ill at ease playing himself, making his self-impersonation unpersuasive.

Tina Fey is the creator of the show and also appears in it. In real life she has a family and a very busy schedule - here's a quote from a recent interview:
"At home,” she added, “I cry” — about, among other things, not being home enough.