Rosetta space mission - Philae probe due to land on comet on 12th Nov 2014
- Thread starter editor
- Start date
farmerbarleymow
I'm Petee's spirit animal
Excellent news! That's cheered me right up. 
Steel Icarus
ersatz maven
Excellent news! That's cheered me right up.
Me too. I even like the cutesy tweet 'from' Philae - "How long have I been asleep?"
2hats
Dust.
Short conversation of mainly housekeeping data (*). Sounds like it is in reasonable health with sufficient power to commence science operations. It appears it had been collecting data for several days before and attempting to uplink it but pass geometry and operational issues precluded this happening. There is quite a lot of locally stored data which will take a little bit of time to relay back and process.
e2a: * an 85 second chat, half of which provided data according to the CNES.
e2a: * an 85 second chat, half of which provided data according to the CNES.
Last edited:
TheHoodedClaw
acknowledging ur soup leg
Tonight's edition of The Sky at Night is a Rosetta special too.
2hats
Dust.
A little more information from the Rosetta mission manager: Philae is currently at -36 degC and has 24 Watts of power available (it needs to be above -45C and have more than 19W available in order to operate). The next step is to establish a stable communications pattern between Philae and Rosetta and then (within about a week or so) planned lander science operations can probably recommence.
2hats
Dust.
Looks like the theoretical relay window (lander-orbiter) is around 2 minutes every 10 hours at the moment. It will take some time to dump the backlog of data from Philae to Rosetta in such circumstances(++). Possibly there is some leeway for optimising Rosetta's orbit to widen this window(*), based on refined location data derived from the radio signal, and without compromising science data collection by the orbiter itself (to any significant degree).
e2a: * ESOC have indeed confirmed that they are currently working on modifying the trajectory of Rosetta to achieve this($$).
2e2a: ++ I calculate ~10 days at a rate of one 2 minute conversation every 10 hours.
3e2a: $$ amusingly the science team were together in Rome last week for a meeting specifically about optimising Rosetta's orbit to improve communication with Philae. So those ideas are now being implemented.
e2a: * ESOC have indeed confirmed that they are currently working on modifying the trajectory of Rosetta to achieve this($$).
2e2a: ++ I calculate ~10 days at a rate of one 2 minute conversation every 10 hours.
3e2a: $$ amusingly the science team were together in Rome last week for a meeting specifically about optimising Rosetta's orbit to improve communication with Philae. So those ideas are now being implemented.
Last edited:
2hats
Dust.
And as luck would have it there's a Sky at Night update on the Rosetta mission tonight at 8pm on BBC4. Except it was brewed up before the news today so here is a quick update to go with it.
Impossible Girl
Time traveller and Companion
Oh hello Philae, so long no see... nice to hear from you
coley
Well-Known Member
2hats
Dust.
Update from the lander control centre: all lander sub-systems are working correctly. They have sufficient data from a full day-night cycle to determine that Philae is sunlit for around 3 hours each 'day' (12 hours) - the solar panels are able to charge the battery for about 135 minutes of that. The lander's internal temperature is around -5 degC; the project manager stated "it appears that the lander is in as good a condition as we could have hoped". Currently they are working to retrieve just over 2MB of data stored on the lander which may have been taken over the last few days or even weeks. The plan is then to conduct 'passive' science (ie no drilling or hammering) until the local environment and power situation is fully characterised (and there is sufficient power to drive the drill/hammer without compromising any other activity).
(Edited to correct quantity of stored data).
(Edited to correct quantity of stored data).
Last edited:
brogdale
Coming to terms with late onset Anarchism
2hats
Dust.
An update: nothing was heard from Philae Monday through Tuesday morning but this is not unexpected as, due to the fact that it was taking preplanned science data observations, Rosetta's orientation and position were unfavourable for hearing the lander. This morning a manoeuvre is being conducted to lower Rosetta's trajectory from just over 200km down to 180km altitude, a second burn will follow on Saturday. The idea is to reproduce the geometry of the first contact, at a closer range and with optimum orientation (during each daily communications window Rosetta will be pointed towards the lander) in order to maximise the data return from Philae.
There's an ESA press conference "Rosetta - discoveries and expectations" being broadcast live from the Paris Air Show (link), which starts shortly at 0830BST this morning.
e2a: replay of the press conference here.
There's an ESA press conference "Rosetta - discoveries and expectations" being broadcast live from the Paris Air Show (link), which starts shortly at 0830BST this morning.
e2a: replay of the press conference here.
Last edited:
2hats
Dust.
'Moons' of Comet 67P - four small pieces (tens of centimetres) broken off from the comet nucleus have been spotted in bound orbits around the comet using Rosetta's OSIRIS camera (images taken in September 2014). Unbound objects have also been spotted (the one identified in the image below is actually one such; the streaks are very small specks of dust/ice moving close to the camera, momentary points of light most likely cosmic ray hits on the detector). It is suspected that they (the bound objects, obviously) may have been accompanying the comet from (at least) the last perihelion passage (closest approach to the sun) since either side of perihelion there is insufficient insolation (solar energy input) to eject material of this size (or larger) from the surface of the nucleus (see first paper).
More details.
Also, MIRO, a microwave instrument on Rosetta has been mapping water in the coma, the near-nucleus environment:
More details.
More details.
Also, MIRO, a microwave instrument on Rosetta has been mapping water in the coma, the near-nucleus environment:
More details.
Last edited:
2hats
Dust.
The DLR lander control centre report that during this afternoon's 19 minute long conversation (minus a couple of short interruptions) they established that Philae is in good health, internal battery operating at 0 degC. This means it can store energy and now operate overnight. The data also indicate that Philae was awake in early May but wasn't able to contact Rosetta at that time.
2hats
Dust.
ESA have confirmed funding for the Rosetta extended mission up to September 2016 at which point the orbiter will be commanded to slowly spiral down and land on the surface of the nucleus (perhaps able to send data right up until landing). It will also probably execute some very low flybys in 2016, after the upcoming perihelion (when activity and thus risk from dust/gas/other ejecta has substantially reduced), in order to image the lander Philae on the surface.
Similar threads
