[meteorite-list] Venus Express Anomaly

[Ron Baalke]

http://blogs.esa.int/rocketscience/2014/12/05/venus-express-anomaly/

Venus Express anomaly
ESA Rocket Science Blog
December 5, 2014

On 28 November 2014, the flight control team at ESOC reported loss of 
contact with Venus Express.

It is possible that the remaining fuel on board VEX was exhausted during 
the recent periapsis-raising manoeuvres (see blog post here) and that 
the spacecraft is no longer in a stable attitude (the spacecraft's high-gain 
antenna must be kept pointed toward Earth to ensure reliable radio contact).

Repeated attempts to re-establish contact using ESA and NASA deep-space 
tracking stations have been made since then, and there has been some limited 
success in the period since 3 December.

Although a stable telemetry link is not available, some telemetry packets 
were successfully downlinked. These confirm that the spacecraft is oriented 
with its solar arrays pointing toward the Sun, and is rotating slowly.

The operations team is currently attempting to downlink the table of critical 
events that is stored in protected memory on board, which may give details 
of the sequence of events which occurred over the past few days. The root 
cause of the anomaly (fuel situation or otherwise) remains to be established.

We will provide an update as soon as something more concrete is known.

Today, Venus Express is in the eighth year of its fantastic mission -- 
pretty good for a satellite originally designed for just two years of 
orbiting in Venus' challenging conditions.