[NewCandle] More spacecraft velocity anomalies

[Keith Nagel]

Here's a little more about the anomaly.

http://www.space.com/scienceastronomy/080229-spacecraft-anomaly.html

Physical Review Letters will publish the upcoming paper.

>From the article:

"The researchers looked at six deep-space probes - Galileo I and II to
Jupiter, the NEAR mission to the asteroid Eros, the Rosetta probe to a
comet, Cassini to Saturn, and the MESSENGER craft to Mercury. Each
spacecraft flew past the our planet to either gain or lose orbital energy in
their quests to reach their eventual targets.

In five of the six flybys, the scientists have confirmed anomalies.

"I am feeling both humble and perplexed by this," said Anderson, who is now
working as a retiree. "There is something very strange going on with
spacecraft motions. We have no convincing explanation for either the Pioneer
anomaly or the flyby anomaly."

In the one probe the researchers did not confirm a noticeable anomaly with,
MESSENGER, the spacecraft approached the Earth at about latitude 31 degrees
north and receded from the Earth at about latitude 32 degrees south. "This
near-perfect symmetry about the equator seemed to result in a very small
velocity change, in contrast to the five other flybys," Anderson explained -
so small no anomaly could be confirmed.

The five other flybys involved flights whose incoming and outgoing
trajectories were asymmetrical with each other in terms of their orientation
with Earth's equator.

For instance, the NEAR mission approached Earth at about latitude 20 south
and receded from the planet at about latitude 72 south. The spacecraft then
seemed to fly 13 millimeters per second faster than expected. While this is
just one-millionth of that probe's total velocity, the precision of the
velocity measurements was 0.1 millimeters per second, carried out as they
were using radio waves bounced off the craft. This suggests the anomaly seen
is real - and one needing an explanation.

The fact this effect seems most evident with flybys most asymmetrical with
respect to Earth's equator "suggests that the anomaly is related to Earth's
rotation," Anderson said."