![]() ![]() Ptolemy and COSAC begin science descent data transmitted to Rosetta Note: times for subsequent events are relative to actual landing time.ĬIVA panoramic imaging (transmitted to Rosetta immediately) Thruster fires for 15 seconds harpoons fire flywheel turns off. Lander completes pre-touchdown operationsĮxpected Landing (time approx). Start imaging landing site switch on active descent system (cold jets that will push lander against surface) Start CIVA and ROLIS switch on lander anchor Start of downlink of stored data, including CIVA "farewell" imageĮarliest possible release of NavCam and/or CIVA "farewell" images Lander completes post-separation activities Rosetta divert maneuver loss of signal due to slew Lander begins rotation of 14 degrees to stable landing orientation Lander/orbiter separation distance 100m earliest landing gear and ROMAP boom deployment Lander CIVA camera photographs orbiter (FAREWELL2) Lander CIVA camera photographs orbiter (FAREWELL1) Separation, Descent, and Landing phase begins Lander separation, 94-second window, separation at 18 cm/s, 22.5 km from comet. Start internal automated sequence to prepare for landing Start CIVA and ROLIS switch on SESAME dust sensor Start MUPUS operation switch on CIVA and ROLIS imagers Rosetta pre-delivery maneuver (lining up for separation) ![]() Start heating lander batteries to separation temperature Rosetta start executing on-board commands for delivery operations Start switching lander instruments on ROMAP is first Go/no-go decision 3: Confirm Philae ready for landing (This decision was delayed about an hour due to problem with cold-gas jet system on lander) Lander generates final telemetry for separation decision Go/no-go decision 2: Confirm lander sequence and Rosetta ready for separation Rosetta starts slew to pre-delivery attitude (expected loss of signal) Go/no-go decision 1: ESOC Flight Dynamics confirms Rosetta on correct trajectory Lander batteries and compartment heating ADS tank openingĢ4-hour ESA #CometLanding Livestream begins Media-related events are highlighted yellow mission control events in orange and the major separation and landing events in red, most of it taken from this timeline released November 7 by ESA (PDF). What will we know, when? Below is a timeline of Philae events, and a brief summary of what Philae intends to do. In contrast, almost all of Philae's science will not come until after a successful landing. But Huygens did almost all of its science on the way down, returning all its data to the Cassini orbiter in real time, so it didn't matter whether Huygens survived its arrival on Titan's surface. ![]() We don't really know what the surface of a comet is like - is it a hard, crusty shell of rocky material? A diaphanously fluffy, almost cloud-like layer of highly porous dust? Gravelly? Crunchy? Crystalline? Powdery? Sandpapery? Slippery? Who knows? The last time we landed on a surface that we knew so little about was when ESA landed Huygens on Titan in 2004. It's just that we have never landed on anything like a comet before. To be clear, I have no specific doubts about the spacecraft or its designers. I'm not going to lie to you: I'm going to be terrified about Philae's survival until I see ESA engineers leaping from their seats and cheering. Hopefully, Philae will survive the landing, and begin to return data.Īll next week, I'll be in Darmstadt, Germany, at the European Space Operations Centre (ESOC), to witness the historic attempt at landing on a comet. Seven hours later, it will arrive at the surface of the comet. Philae has warmed up its science instruments and has even taken a couple of amazing photos of the comet with Rosetta's solar panel in the foreground, but the lander doesn't really begin to get to work until November 12 at 8:35 UT, when it will finally separate from the orbiter. ![]()
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