PHILAE Science Team, Venice LTS phase: the LS standpoint prepared by HBO LTS phase: from end of FSS (mid Nov. 2014) to end of Rosetta mission (31 Dec. 2015), i.e. from ~3AU before to 2AU post-perihelion limiting factor may be lifetime of PHILAE, rather than ROSETTA (current estimates: ~2 AU pre-perihelion?) SC objectives: Objective 8 = long-term science (but also other PHILAE objectives are followed up during LTS) LTS science objectives: all PHILAE experiments have LTS science objectives HBO expectation: FSS gives a taste of cometary science, LTS provides synopsis of cometary science for future text book chapters

PHILAE Science Team, Venice 20092

3 LTS phase: the LS standpoint prepared by HBO LTS phase minimum success criterion: measurements for at least four about equally distributed solar distances when the comet approaches the Sun from 3 to 2 AU, i.e. between mid Nov to end March 2015  2.75, 2.5, 2.25, 2.0AU  ~ once a month reasoning: non-linearity of T increase, gas & dust production (strong increase of H2O plus organics), change of surface structure, decoupling of cometary surface from interaction with solar wind, day-night cycle  sampling by ‘more than 3 data points  LTS + FSS should cover activity onset by at least 5 measurements per experiment for the characterization of the comet behaviour

PHILAE Science Team, Venice LTS phase: the LS standpoint prepared by HBO Experimenters’ expectations: typically every 0.1AU  ~ once every two weeks (also more frequently)  possibly a mixture of more continuous measurements (MUPUS, ROMAP, SESAME) and periodic ones (APXS, CIVA, COSAC, PTOLEMY, ROLIS, SD2) and campaign-like ones (CONSERT) might be a reasonable approach An updated thermal model of PHILAE would be useful to have

PHILAE Science Team, Venice LTS phase: the LS standpoint prepared by HBO LTS operation modes: operation modes defined by LTS engineering group survival is prime aspect science and battery charging are key aspects trade-off between short-term science and long-term prospect of science through battery usage is important  it is worthwhile considering science by a low power user instead of continuous battery recharging at inefficient level expectation: MOST tool allows the analysis the Lander LTS operation options  experimenters have to accept that lander survival and long- term science prospect rules over immediate experiment objectives

PHILAE Science Team, Venice LTS phase: the LS standpoint prepared by HBO Impacts on SDL & FSS phases:  SDL - landing site selection should consider optimized location for LTS, i.e. from solar illumination and power point of view  FSS – consider – as an option - battery usage for early LTS operations phase 2.75AU) Landing site selection: * safety of descent, landing and survival * scientific criteria * operational criteria