A timeline of the most crucial activities related to separation, descent and landing on 11 and 12 November.

What does Philae do during descent? Credit: ESA/ATG medialab

What does Philae do during descent? Credit: ESA/ATG medialab

It has been compiled with inputs from the Flight Control Team at ESOC and the Science Operations Team at ESAC and is accurate as of now. PLEASE remember: many of these times are subject to change and confirmation, given the extremely dynamic nature of this delicate and complex operation. We’ll do our best to update this as we receive firm information, but on 12 November the live webcasts from ESA TV and ESA’s social media accounts (Twitter!) will be the best ways to get the latest information.

Admittedly, this timeline is a little dense, but we thought it better to provide more detail for those who – like us! – are extreme Rosetta & Philae fans (and you know who you are!). We’ll publish a lighter version in the main ESA website later today and there’s also a high-level version in the press kit (PDF; page 63 or in SlideShare here). And for those who wish, here is the opposite: an even more detailed version as a PDF, or also in Slideshare.

Review the notes/legend underneath for acronyms (no space mission can succeed without them!). There’s also a diagramme illustrating the delivery orbits.

ROSETTA AND PHILAE OPERATIONS TIMELINE AROUND COMET LANDING 11-12 NOVEMBER 2014

All times are subject to change and should not be assumed confirmed. Actual times may vary considerably. Please follow ESA TV, the Rosetta website, the Rosetta blog and ESA social media for the latest updates. All are linked via https://rosetta.esa.int

One-way light time (OWLT): 00h:28m:20s
Earth distance: 511 million km
CET/UTC offset: 01h:00m:00s
Updated 8.11.2014 to correct 12/11 04:28UTC event and add 01:00UTC event
Updated 12.11.2014 to indicate new GO/NOGO time for Philae lander, now at 02:35 UTC / 03:35 CET

 

Date

UTC
on Earth

CET
on Earth

Event

11/11 01:48:49 02:48:49 BOT ESA New Norcia (NNO)
11/11 03:10:00 04:10:00 BOT NASA DSN Canberra
11/11 12:25:00 13:25:00 EOT Canberra
11/11 13:40:00 14:40:00 BOT DSN Madrid
11/11 13:58:05 14:58:05 BOT ESA Malargüe (MLG)
11/11 14:00:00 15:00:00 Flight Dynamics Team at ESOC begin orbit determination procedure to accurately fix Rosetta’s precise trajectory
11/11 14:30:17 15:30:17 EOT ESA NNO
11/11 18:33:20 19:33:20 Lander switch-on. Includes switching on Electrical Support System, which controls orbiter communication interface with the lander
11/11 19:05:20 20:05:20 Lander batteries and compartment heating
ADS Tank (Active Descent System – provides cold gas thrust upwards to avoid rebound upon landing) opening
11/11 19:25:20 20:25:20 Lander Primary Battery conditioning start; about 28 mins
11/11 19:00:00 20:00:00 EOT DSN Madrid
11/11 19:30:00 20:30:00 GO/NOGO1 – Last full orbit determination; ESOC Flight Dynamics confirms Rosetta trajectory is correct
11/11 20:03:00 21:03:00 Rosetta starts slew to pre-delivery manoeuvre attitude (expected loss of signal)
11/11 20:20:00 21:20:00 BOT DSN Goldstone
11/11 20:43:00 21:43:00 End of Rosetta slew
11/11 20:52:20 21:52:20 Start Lander flywheel operation – provides stability during descent
11/11 23:25:00 00:25:00 BOT DSN Goldstone
11/11 23:40:00 00:40:00 BOT DSN Canberra
12/11 00:00:00 01:00:00 EOT DSN Goldstone
12/11 00:00:00 01:00:00 GO/NOGO 2(a) – Confirm telecommands to control delivery sequence are ready
GO/NOGO 2(b) – ESOC confirms Rosetta is ready
12/11 01:00:00 02:00:00 ESOC uploads commands to control spacecraft for Lander delivery operations
12/11 01:03:20 02:03:20 Lander generates final telemetry (TM) on-board prior to GO/NOGO for SEP decision
12/11 01:35:00 02:35:00 (EXPECTED AT 02:35 UTC / 03:35 CET) GO/NOGO 3 – Confirm Philae is ready for landing
12/11 01:46:10 02:46:10 BOT ESA New Norcia
12/11 03:02:50 04:02:50 EOT ESA Malargüe
12/11 04:03:20 05:03:20 Lander – start of Separation, Descent & Landing (SDL) activities
Start switching Lander instruments ON; ROMAP first
12/11 04:28:20 05:28:20 Rosetta – Start executing on-board commands for delivery operations
12/11 04:34:20 05:34:20 Start heating Lander batteries to separation temperature
12/11 06:03:20 07:03:20 Rosetta – Earliest start pre-delivery manoeuvre (thruster burn)
Burn will be followed by loss of signal due to subsequent slew for separation
Manoeuvre expected to be about 0.46m/s & about 6 mins duration

Date

UTC
on Earth

CET
on Earth

Event

12/11 06:35:00 07:35:00 Earliest GO/NOGO 4 – final decision to go for landing
12/11 07:03:20 08:03:20 Rosetta – Latest start pre-delivery manoeuvre
12/11 07:35:00 08:35:00 Latest GO/NOGO 4 – final decision to go for landing
Following MVR, ESOC Flight Dynamics Team conducts rapid assessment of MVR performance to verify burn results
12/11 07:49:20 08:49:20 Lander – Switch on MUPUS
12/11 07:52:20 08:52:20 Start MUPUS operation and switch-on CivaRolis
ÇIVA and ROLIS are imaging systems; ÇIVA makes panoramic images, ROLIS looks down
12/11 07:55:20 08:55:20 Start CivaRolis operation and switch-on SESAME (dust sensor)
12/11 08:04:20 09:04:20 Start SESAME operation
12/11 08:46:20 09:46:20 Start MSS (Mechanical Support System), which executes the mechanical separation from the Orbiter
12/11 08:46:20 09:46:20 Separation Motors ON
12/11 08:49:20 09:49:20 Start CONSERT Orbiter operation
12/11 08:50:20 09:50:20 Start CONSERT Lander operation
12/11 08:51:20 09:51:20 Start MSS sequence – internal autosequence to prepare for landing
12/11 08:53:20 09:53:20 Lander now on internal battery power
12/11 Screws in Separation Motors start to rotate and impart deployment speed to push Lander away, retrograde .21 m/s
12/11 09:03:20 10:03:20 PHILAE SEPARATION (Forecast; 94-sec window)
Separation confirmation received on ground via ESA’s NNO New Norcia station
12/11 09:04:12 10:04:12 Lander (ÇIVA) obtains first images of Orbiter (FAREWELL1)
12/11 09:06:17 10:06:17 Lander (ÇIVA) obtains seconds images of Orbiter (FAREWELL2)
12/11 09:12:17 10:12:17 Lander / Orbiter separation distance now ~100m
Earliest autodeployment of landing gear and ROMAP boom antenna
12/11 09:25:50 10:25:50 Lander starts rotation of 14 degrees to stable landing orientation
12/11 09:43:20 10:43:20 Rosetta performs post-delivery manoeuvre
Burn will be followed by loss of signal due to subsequent slew back to nominal pointing
Manoeuvre magnitude to be determined on 12/11
12/11 09:47:17 10:47:17 Lander completes all post-separation activities
12/11 10:53:20 11:53:20 Acquisition of signal (AOS) from Rosetta
Expected AOS; link with Rosetta now re-established
12/11 11:59:20 12:59:20 Start of stored data downlink from Rosetta & Philae
12/11 12:20:00 13:20:00 EOT DSN Canberra
12/11 13:15:00 14:15:00 BOT DSN Madrid
12/11 13:55:00 14:55:00 BOT ESA MLG
12/11 14:27:00 15:27:00 EOT NNO
12/11 14:58:57 15:58:57 Lander – switch-on Anchor & CivaRolis

Date

UTC
on Earth

CET
on Earth

Event

12/11 15:01:57 16:01:57 Lander – start imaging landing site and switch on ADS (Active Descent System)
12/11 15:07:02 16:07:02 ROLIS begins imaging
12/11 15:17:15 16:17:15 On board Lander, systems conduct final pre-touch-down operations
12/11 15:22:20 16:22:20 Start of Lander touch-down window
12/11 16:02:20 17:02:20 EXPECTED LANDING and receipt of signal (Forecast; 40 min variability)
12/11 Upon landing – start post-touch-down operations including:
* ADS thruster fires for ~15 sec to avoid rebound
* Harpoons (X2) fire to secure Lander to surface
* Flywheel off
12/11 16:07:12 17:07:12 ÇIVA-P panoramic imaging on
Lander obtains first images of surface and transmits same (forecast; depends on landing time)
12/11 16:07:14 17:07:14 Separation, Descent & Landing (SDL) science observations continue: Ptolemy & COSAC begin science gathering; data collected during descent and initial surface observations will be uploaded
12/11 16:39:39 17:39:39 Lander completes SDL operations; upload of science data
12/11 17:49:07 18:49:07 Lander begins First Science Sequence (FSS) Block 1; runs about 7 hours
12/11 19:00:00 20:00:00 EOT DSN Madrid
12/11 19:03:00 20:03:00 End of Lander/Orbiter first communication window
13/11 01:43:00 02:43:00 BOT ESA NNO
13/11 02:59:00 03:59:00 EOT ESA MLG

Keen for more details? Download the extended version of this timeline here.

Notes:

BOT Begin of track
EOT End of track
NNO ESA – ESTRACK 35m New Norcia tracking station, Australia
MLG ESA – ESTRACK 35m Malargüe tracking station, Argentina
LDR Philae Lander
ROS Rosetta Orbiter
LCC Lander Control Centre, DLR/Cologne
ESOC Rosetta Control Centre, ESA/Darmstadt
ROLIS Rosetta Lander Imaging System (ROLIS): CCD imager designed to return images of the landing site before and after Philae has landed
ADS Active Descent System (ADS) – this system emits cold gas thrust at touchdown to avoid rebound.
BOT Indicates when station is pointing & ready. Actual acquisition of signal may come only afterwards
DSS 25 NASA – DSN 34m Goldstone tracking station, California, USA
DSS 45 NASA – DSN 34m Canberra tracking station, Australia
DSS 55 NASA – DSN 34m Madrid tracking station, Spain
DSS 54 NASA – DSN 34m Madrid tracking station, Spain
MVR Manoeuvre – a thruster burn to change direction and/or speed
MSS (Mechanical Support System) is the lander side of Philae which executes the mechanical separation from the orbiter.
ESS ESS (Electrical Support System) is the orbiter part of the lander. The ESS controls the orbiter communication interface with the lander. ESS itself operates as usual as power and data interface to the Orbiter.

Link to Lander science instruments via https://www.esa.int/Our_Activities/Space_Science/Rosetta/Lander_Instruments

CIVA, CONSERT, COSAC, PTOLEMY, MUPUS, ROLIS, ROMAP, SD2, SESAME

 

Labelled diagram indicating Rosetta’s trajectory from the end of October until early December. Credit: ESA

Labelled diagram indicating Rosetta’s trajectory from the end of October until early December. Screenshot from video. Credit: ESA