Operational history

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The major operational phases and milestones are:

1. Launch and transfer to orbit: (provide date, and summary overview)

Planck was launched from the Centre Spatial Guyanais in Kourou (French Guyana) on 14 May 2009 at its nominal lift-off time of 13:12 UT, on an Ariane 5 ECA rocket of Arianespace2. ESA’s Herschel observatory was launched on the same rocket. At 13:37:55 UT, Herschel was released from the rocket at an altitude of 1200 km; Planck followed suit at 13:40:25UT. The separation attitudes of both satellites were within 0.1 deg of prediction. The Ariane rocket placed Planck with excellent accuracy (semimajor axis within 1.6% of prediction), on a trajectory towards the second Lagrangian point of the Earth-Sun system (“L2”). After release from the rocket, three large manoeuvres were carried out to place Planck in its intended final orbit. The first (14.35 ms−1), intended to correct for errors in the rocket injection, was executed on 15May at 20:01:05 UT, with a slight overperformance of 0.9% and an error in direction of 1.◦ 3 (a touch-up manoeuvrewas carried out on 16 May at 07:17:36 UT). The second and major (mid-course)manoeuvre (153.6ms−1) took place between 5 and 7 June, and a touch-up (11.8 ms−1) was executed on 17 June. The third and final manoeuvre (58.8ms−1), to inject Planck into its final orbit, was executed between 2 and 3 July. The total fuel consumption of these manoeuvres, which were carried out using Planck’s coarse (20N) thrusters, was 205 kg. Once in its final orbit, very small manoeuvres are required at approximately monthly intervals (1 ms−1 per year) to keep Planck from drifting away from its intended path around L2. The attitude manoeuvres required to followthe scanning strategy require about 2.6 ms−1 per year. Overall, the excellent performance of launch and orbit manoeuvres will lead to a large amount (∼160 kg, or ∼40% of initial tank loading) of fuel remaining on board at end of mission operations.

2. Calibration and Performance Verification: (provide date, and summary overview)

3. Nominal Mission: (provide date, and summary overview)

4. Extended Mission: (provide date, and summary overview)

5. LFI-only phase: (provide date, and summary overview)

5. End-of-life: (provide a vague estimation)

Provide a description of the product Planck Operational State History.

European Space Agency

(Planck) Low Frequency Instrument