We received a nice note yesterday from ESA's Jean-Michel Bois, Mission Director at ATV-CC, explaining details on the work involved with planning and scheduling communications with ATV-2.
Since ATV separated from its Ariane launcher on 16 February, all communications between ATV Control Centre (ATV-CC) in Toulouse and the vessel - receipt of telemetry and sending of telecommands - have been achieved via data relay satellites. Two relay satellite systems are in use: NASA's Tracking and Data Relay Satellite System (TDRSS) and ESA's own Artemis satellite.
During the current 'phasing' period (i.e. manoeuvring so as to match the ATV orbit with that of the ISS), ATV is communicating primarily via NASA's TDRSS. ATV-CC is using Artemis as a back-up and as a complement when TDRSS communication slots are not available.
The TDRSS satellites can ensure communication during ATV's complete orbit (about once every 90 minutes) thanks to the fact that the system comprises multiple satellites. These are set in a ring in permanent geosynchronous orbit with at least one looking down on all regions the Earth (and on ATV as well!).
ESA's single Artemis satellite is also in geo-orbit, located at 21.4ºE, and offers around 40 minutes of continuous contact during each of ATV's orbits. ESA's Redu station, in Belgium, houses the Artemis mission control room (more details here).
At ATV-CC, it's the task of mission planners and the 'Ops Manager' on console to prepare and manage the communication coverage; this team works in very close coordination with their NASA and Redu counterparts.
Jean Michel Bois in ATV-CC just prior to launch 16 Feb 2011
A short but very pleasant note came in this morning from ESA's Jean Michel Bois, head of the ESA team here at ATV-CC, who was on shift as Mission Director in the main control room during last night's launch and LEOP (launch and early orbit phase). He wrote:
The Sun's up this morning and the LEOP phase of ATV-2 is over. What a fabulous night! ATV Johannes Kepler is now in the sky and ready for its first manoeuvres to chase after the ISS.
After the disappointment on the 15th when the Ariane countdown was stopped a few minutes before the lift-off, yesterday was a perfect Ariane 5 mission - ending with a very accurate injection into orbit. The level of pressure at ATV-CC was very high as our teams waited for ATV's separation from the upper stage, ready to take control of the vehicle. When the first telemetry from ATV was received by our computers, we knew that launch - a major step - was a success.
Then, one after the other, we could watch the pre-planned events happening on our screens as ATV's systems came to life! These included:
Approximately 15 media from Germany and Belgium were present, and the Q&A session - with Mission Director Capelle, Head Engineer Leiseifer and astronauts De Winne and Gerst - was quite lively. Listen to the audio recording below and click on 'continue reading' to access the PPTs.
ESA Mission Director Kris Capelle: ATV’s mission uncovered
We met last week at ATV-CC with ESA's lead Mission Director, Kris Capelle, who oversees all operational aspects of the Johannes Kepler mission. In today's video, he talks us through the complete ATV mission profile from launch to reentry, and provides an authentic, 'working-level' view into the challenges of flying Europe's sophisticated ISS cargo vessel.
When Artemis talks, Johannes Kepler listens
Redu station: 13.5 m tracking antenna is part of ESA's ESTRACK network
There's a nice report this morning in ESA's Telecoms website on the role of the Agency's Artemis data rely satellite in ATV communications.
During phasing, rendezvous, docking, undocking and reentry, ATV primarily communicates via NASA's Tracking and Data Relay Satellite System (TDRSS) - and uses Artemis as backup. During the docked or attached phase, ATV uses Artemis as its main relay. A little later, we'll post a more detailed overview of all the ways in which ground controllers and astronauts can communicate with ATV.
After Ariane 5 lofts ATV Johannes Kepler into space on 15 February, ESA’s Artemis data relay satellite will be ready for action. Artemis will provide communications between Johannes Kepler and the ATV Control Centre (ATV-CC) in Toulouse, France. Hovering some 36 000 km above the equator at 21.4ºE, Artemis will route telemetry and commands to and from the control centre whenever the satellite sees the International Space Station or ATV. During every ATV-2 orbit, there is close to 40 minutes of continuous contact.
Times in UTC
6/05 - ATV-4 moves to the BAF for final preparations
8/05 - ESA Operations Readiness Review
20/05 - Late-cargo loading
31/05 - Launch Readiness Review (planned)
5/06 Lift-off VA213 (planned) All dates subject to change