MEETING

meeting date 9-12th March 2009 ref./réf. page/page 1 date de la réunion 18 meeting place ESA-ESTEC, ERASMUS Auditorium chairman Jason P Hatton (ESA HSF-US) lieu de la réunion présidant minute’s date 19th March 2009 participants See Attendee list dates de minute participants subject/objet Minutes of Meeting – Jules Verne copy/copie John Ellwood (ESA D/SRE) Multi-instrument aircraft campaign intermediate science results description/description action/action due date/date limite

Monday 9th March 2009

Introduction from John Ellwood (ESA, ATV Project Manager): John Ellwood thanked the science team for their hardwork in performing the campaign. There had been a Long standing interest in doing observations of ATV reentry during ATV development, but initial assessments were not feasible. JV-MAC campaign proposed in late 2007 & succeeded in obtaining detail observations of the reentry

Introduction from Tomasso Sgobba (ESA, Chairman of ATV Reentry Safety Panel): Proposed this workshop should be the start of a series of workshops to discuss reentry safety. Future missions may include HTV.

Mike Steinkopf (ESA, ATV Mission Director for Reentry Operations). “ATV-CC Mission operations & MAC team interfaces during re-entry observation” See PDF presentation #1 Presented mission operations. Explained modification of post undocking mission to facilitate reentry observations during night which was a requirement of the JV-MAC mission. Also ISS observations (FIALKA) required phasing manoeuvres to put ATV under ISS at time of reentry. The result was a delay of 24 days from undock until reentry. Coordination of JV-MAC reentry observations with ATV-CC, required close cooperation to ensure mission success. This was done through an interface control document, with first trajectory data provide at R-27d, then updates at intervals until R-1day. Also inflight updates of trajectory information were provided by satellite phone to both aircraft. Communications tests identified some off nominal communications issues, but this resolved by retrying & troubleshooting in the case of the Gulfstream V Inmarsat phone.

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ESTEC JV-MAC-MoM-9-12Mar2009-v5- Keplerlaan 1 - 2201 AZ Noordwijk - The Netherlands draft Tel. (31) 71 5656565 - Fax (31) 71 5656040

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Jason Hatton (ESA, JV-MAC coordinator on ESA side) “Jules Verne MAC observation campaign: overview of mission concept, planning & operations” See PDF presentation #2. The general concept of the mission was presented, including instrument package objectives, general organisation & a brief overview of the raw instrument data Q. from audience – how was ATV apparent attitude (eg. elevation / azimuth) data aquired = A. star field + GPS & astrometry of fragments position relative to star field.

Jim Albers (SETI Institute, Aircraft flight planning) “ATV Reentry – Aircraft flight planning, execution & lessons learned”. See PDF presentation #3. Flight planning – presented general concept & planning. The aircaft needed to be turned to follow ATV. Effect of wind had to be incorporated into planning, to ensure aircraft pointing in the correct direction. For the Gulfstream V, the most critical parameter was timing of the turn, uncertainties in trajectory were of less concern. Conversely for the DC-8 the trajectory variation (long or short) would require the angle & duration of turn to be varied. Therefore, it was necessary to react in real time to any variations in trajectory. During mission the trajectory of the main fragment was longer than predicted, DC-8 tried to react but increased turn too late to adequately follow main body. Inflight a spreadsheet was used to update the reference points for the aircraft manoeuvres. Three waypoints were provided by satellite telephone which were then input into the spreadsheet. For the GV manoeuvre this was practiced during observation flight approx half hour prior to reentry. Exchange of trajectory data prior to mission practiced & verified. Actual flight paths presented. There was a significant cross wind (100kt) which resulted in some differences in position WRT original plan. This was compensated by flight crew, pointing of aircraft WRT ATV was correct. Actual initial points shifted, but pointing of aircraft was relatively insensitive to absolute position. Also some replanning in Tahiti, GV position moved back to provide better coverage by some instruments (aircraft positioned ~20km further back to permit Clay Center Observatory spectrograph to cover entire trajectory) Lessons learned: Generally went well, but some improvement possible. Good coordination with ATV-CC. First time aircraft turned during observations in a MAC mission, this generally worked well but some constraints particularly for DC-8. Better coordination needed between observers & flight planning early in process. Some aircraft pointing errors. Internal comms in GV good in cockpit, but difficult to get feedback from observers & GV cockpit. In DC-8 inputs from observers to crew through headset, but 1-2 people between observers & pilots which delays transfer of information.

Peter Jenniskens (SETI Institute: JV-MAC Principle Investigator). “Overview of status of analysis & key results to date – ATV-1 Jules Verne MAC” See PDF presentation #4 Overview of status of analysis & key events. The overall timeline was presented which shows the key events. The main explosion resulted in a glowing cloud. The ATV intensity did not increase according to the theoretical light curve. No clear indication of tumbling in photometric data. A number of flares were observed prior to explosion. Brightening faster than predicted may be result of ablation processes. Slitless was spectroscopy used extensively, permitting direct imaging plus spectra. Visual example is DSLR slitless spectroscopy, the AlO & Sodium spectra are quite apparent on the image. A Series of flares & flashes seen preceeding the main explosion, the earliest flares had a very strong emission of magnesium. Later flares prior to main explosion released a lot of AlO. Main explosion at 13:36:19UT 29Sep2009. The Main explosion overexposed most instruments, but in INT instrument

MEETING meeting date ref./réf. page/page 3 date de la réunion 18 recorded an unsaturateds reflection in window. After explosion a very strong signal was detected, which turns out to be Lithium this is part of one of the three main objects. Lead object visible after last main fragment break up has a strong line emission. Explosion cloud has a defined brightness

Review of HDTV video’s by Peter Jenniskens & Jason Hatton The video’s from the Gulfstream V and DC-8 were show. The general features & events were explained & how data can be exploited. Antoine Bavandi (ESA, TEC; HDTV camera operator on DC-8) “Number of fragments for E-HDTV recording”. See PDF presentation #5 Fragments were counted from the Utah State HDTV recording. This was compared to the HDTV from NASA-Ames, Antoine’s / Mike Taylor’s camera & low light / intensitifed cameras. When Compared to low light camera images, this does not show significantly more bright fragments. Therefore, the HDTV record can be used for fragment counting, this is important for comparison to models. Estimate 400-500 fragments detected. Q. What is the minimum size of fragments that can be detected. This needs to be calculated based on size & surface area. Perhaps spectroscopy can be used to identify specific fragments (eg. batteries) as a reference to cross calibrate size. Fragment sizes were counted by hand.

Hans Stenbaek-Nielsen (Univ. Alaska Fairbanks; HFRS instrument PI): “ATV Re-entry path by triangulation”. See PDF presentation #6 Triangulation of trajectory from tracking camera’s. Used data from the WATEC camera’s. GPS recordings provide position and time to within a few tens of meters. Look angles determined from background stars. Used software developed by Hans Nielsen, originally developed for chemical cloud tracking (Aurora / upper atmosphere research). Star fitting, reference to SAO catalogue includes spectra characteristics. Calibration for brightness. Images are relatively flat, except at edge of field of view. Distortion of field is not a significant problem for this analysis since field of view is quite small. Data available from both camera’s for a part of trajectory. Initial calculations done for each 10s on main fragment. Each image set presented & calculate triangulated trajectory. One challenge for two point observations is that the same fragment may look different (eg. different brightness) from the two different view points. This can make identification of individual fragments difficult. Text file of look angles available. Accuracy calculations: Pixel resolution gives 100-600m resolution at distance of ATV. GPS accuracy approx 100m. This also defines how many individual fragments can be seen in tracking camera’s. Star field astrometry is a few pixels (eg. limited by refraction effects). The ATV is moving at ~8km/s. Therefore each frame = 250m along track uncertainty (however comparison with high frame rate imagers would allow more accurate along track determination). Refraction is important for negative elevation angles, where stars are not readily visible. Calculated this effect & effect is to shift altitude by ~1km. For brightness estimates most data is saturated. However, this is not a significant problem, since the brightness of the object is expected to follow a Gausian profile, so it may be possible to use this on the ATV data. Software used for this analysis can in principle be used with any imaging data.

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Ed Barker & Mark Mulrooney (NASA JSC; JSC Intensified video camera team) “Analysis of faint fragment photometry and astrometry aquiried via na intensified video camera”. See PDF presentation #7 See presentation. Currently analysed RA/DEC positions. approximately 90 faint fragments extracted. Photometry limited by oversaturation. Relative motion tracked, differences in motion indicative of ballistic coefficient. Some indication of clusters of fragments which may be from a common origon. Interesting light curve (u-shaped), brightens then fades. The mechanism is not clear. Data needs to be converted to lat,long, altitude by comparison to Nielsen trajectory & look angles. Fragments trajectory & brightness data should be compared with spectroscopy data.

Detlef Koschny (ESA, D/SRE. SPOSH camera PI): “Trajectory reconstruction of the ATV reentry from the SPOSH camera images. See PDF presentation #8. This was flight test of SPOSH camera, which is a 120° field of view f0.9 breadboard camera intended for use on spacecraft. Trajectory reconstruction employed adapted code normally used for meteor orbit calculation. The original software was designed for fixed station (not moving airplane) & not below 15degree below horizon. Modified software used for ATV, allowing measurement from moving platform & close to horizon. First camera to detect ATV on horizon. Object was bright & satured later in reentry, also limitation with framerate (~2 frames/sec) & 200-400ms exposures. Limiting astronomical magnitude of +6 to +8mag. Some internal reflections in the window, but not a problem for astrometry. Raw data converted to individual FIT’s files, then astrometry via MaximDL. Astrometry for stars 40-50”for DC-8 (optical window), 80-90” for GV (normal window, some distortion). Trajectory analysis via MOTS (Meteor Orbit & Trajectory Software), implemented via Python. Calculated trajectory, appears lower than reference trajectory, covers only part of trajectory prior to explosion (ie. 90-80km) range. This was subsequently identified as a problem in refraction correction. When the correction was applied the trajectory fitted close to the predicted trajectory. Problems to calculate astrometry after explosion via normal commercial software, since software appears to consider fragments as stars & fit to catalogue fails. Currently testing amateur software (astrorecord) which permits manual fitting. Error bars with position 2-5km (combination of image scale & relatively long exposure). Refraction effects need to be fitted. Ongoing analysis – can do photometric analysis of explosion cloud & light curve of ATV prior to explosion.

Jim Albers (SETI, Aircraft planning): “ATV Reentry – Lead object trajectory determination”. See PDF presentation #9 A Preliminary cross check was made inflight of the observed trajectory recorded on video relative to bright stars (eg. Alpha Centauri). The Inflight assessment from GV looked fairly close to nominal, but from the DC-8 trajectory looked long since this aircraft was positioned close to end of trajectory. Comparisons done to previous trajectory determinations, at DC-8 position the trajectory was comparable with a “long”nominal trajectory even further down the track. Comparison of triangulated trajectory with predicted (Nielsen data) showed good agreement early in trajectory, but main object carried on further. This suggested a high ballistic coefficient than the predicted (mean) trajectory. Predicted trajectory was approximately 200kg/m2. Actual trajectory was closer to 600kg/m2 which corresponds with average for ATV as a vehicle. A predicted trajectory for a 600kg/m2 object was generated for direct comparison with images. A bright point object which was spotted, which may not be ATV fragments – these may be a sunlit satellite. This can be verified by comparison with all satellite search of USSPACECOM data. This is not ISS

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Some interesting fragments looked at, including a bright object above main fragment cloud in DC-8 data, need to cross correlate with GV data. Separate starlike moving object spotted, which appears to be a satellite but cannot discount this is not part of ATV since the view would be heavily foreshortened. Main body impact point is 2.5 degrees of latitude further south (300-400km further along track). Q. How was reference trajectory calculated – A. Probably generated from nominal impact point, which is an average (~40kg/m2) = center of impact point. Toe point = 4000kg/m2 which corresponds to the docking adaptor. For future mission planning it would probably better to use a higher ballistic coefficient for the reference trajectory. Comments: Koppenhwaller – ballistic coefficient may change during reentry as material is lost, it could increase as the object changes shape. In SCARAB mass/shape are calculated at each data point. Could the bright object be the docking adaptor???? Only image in NASA-JSC data, so no cross colleration with datasets. Object visible at 13:39, perhaps it is in the DC-8 SPOSH data (no data does not run that long on DC-8, GV camera had stopped working at this point). Need to check other video data.

General Discussion: Trajectory determination (All) Tools exist to do trajectory analysis. Absolute position determination can be done by triangulation & relative position of individual fragments can be be correlated with this. ATV-CC would like a synthesis of current data at end of meeting. CNES Flight Dynamics – expectation of data. (i) Delta V of fragments from explosions (ii) Estimated ballistic coefficient of fragments. Concerning preliminary analysis of main fragment by Jim Albers, with high ballistic coefficient it appears that the impact point is well within the expected impact footprint. Koppenwalher – very interested to know where explosion occurred – in the main propulsion compartment? or in interstage??? Perhaps the spectroscopy data can provide information on this. Need good cooperation between modellers & observers for ongoing analysis. Peter Jenniskens – Q. to Ed Barker, can you calculate early fragment trajectories back to predicted solar panel disruption.

Tuesday 10th March 2009 Tomasso Sgobba (ESA, ATV Renetry Safety Panel Chairman): “ATV re-entry observation campaign results to improve re-entry safety assessment”. See PDF presentation #10 Safety assessment for reentry – improvement of models with observational data. Mir reentry was observed by amateur video & only limited data obtained (single observation, no triangulation, clouds in view). Nevertheless, important parameters were extracted from these limited observations. For the ATV reentry a detailed safety assessment was performed – it was estimated that 25-38% of the ATV mass would survive reentry. Manouvres were planned to ensure a safe reentry. Defined a safety reentry area = area where probability of fragment falling outside of area is less than 10-5, this ensures a safey for the public of better than 10-7. Declared reentry area = area of exclusion for air & sea traffic (10-2 probability). Also did evaluations of off-nominal situations, including unsafe reentry (controlled but overland, eg. premature shutdown of propulsion system during deorbit) & uncontrolled reentry. ACTA performed an independent assessment of reentry risks for the general population, including effect of shelting inside buildings for different building materials. Overall risk assessment from ESA & independent assessment were similar ~2.4 to 3.4 x 10-5. However, there were some detailed differences. The reentry observing campaign results will provide data to improve the models.

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Suggested priorities for safety assessment; Re-entry operations planning ƒ Size/location of ground footprint ƒ Selected fragments trajectories ƒ Altitude of explosion ƒ Delta-V imparted by explosion Risk assessment update ƒ Number of surviving fragments Validation of models ƒ Full fragment characterisation (materials, demise, ballistic coefficient, trajectory reconstruction) Follow on analysis planned by ESA as part of GSP/GSTP programme It is important to improve the risk assessment, since results from STS-107 accident show that risk to commercial aircraft was ~1:1000. May have a similar risk for uncontrolled re-entries. Q. Is it possible to assess the mass of fragments. A. P.Jenniskens in principle yes, using same principles as for meteor study.

Peter Jenniskens (SETI Institute, JV-MAC PI): “Spectroscopic analysis of reentry events: preliminary results from Echelle, ASTRO and INT”. See PDF presentation #11 Spectroscopic analysis of reentry events. This mission was the first time spectroscopy was used to observe a destructive reentry. Very useful technique for understanding processes occurring during fragmentation. Echelle spectrograph is slitless system, sensitive from 350nm to 880nm. Only selected spectra can be used due to motion blur. Small sequences of spectra taken, with adjustment of exposure between each sequence to adapt to changing object brightness. Approximately 80 useful spectra obtained. Early spectra mainly air plasma emission, early flashes have Mg, later flares have AlO prior to main explosion, After explosion a strong Li signal. Explosion spectra determined from internal reflection in Gulfstream V window. Explosion spectra presented. Spectra of explosion appears to show little or no hydrogen, but some problems calibrating spectra. Q. from Hans Nielsen: What is the lifetime of H atoms at the altitude of the explosion. A. Atoms rapidly stopped with collisions with upper atmosphere. This suggests that fuel did not explode, but explosion was apparently was very strong. Therefore, at this time we cannot say if the fuel did explode. Strong Li released shortly after explosion. There is also a CN band visible before & after explosion. Comment from Heiner Klinkrad: Carbon is found in external insulation. Li signal seen approximately 3-4s after explosion. Perhaps this could indicate the exposure of the batteries at this point. CN signal seen early on the reentry, this would be consistent with ablation of thermal insulation. Also detected Mg, Ni, Ca+, Mn, Ti, Cr, Zn, Ba+, AlO. Slides show spectra just after explosion (black line) & later with fragments at lower altitude (blue line). Comment from Heiner Klinkrad: Cr is consistent with docking adaptor components. Time variation of spectra: prior to explosion – CN, airplasma Na & K (13:35:52UT). Early in reentry primarily air plasma emissions, these can be easily modelled & confirm pre-flight modelling. However predicted N2+ emission not seen. Just after explosion, CN is detected quite strongly. Also strong increase of Na after explosion. Comment from Heiner Klinkrad: ~200kg of Urine in water tanks in the interstage, this could be a good source of Na.

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Very strong line at ~510nm which has not been identified yet. In near IR (760nm) telluric absorption of oxygen. Three fragments separated after explosion, difficult to analyse due to overlapping images in Echelle. Only one of two fragments has Mn present. Also one fragment has no Ti, whereas the other two has a lot of Cr At end of the reentry a lot AlO is detected, as well as continuum – this is not well understood. One spectrum from Astro instrument, due to instrument problems. However, one spectra obtained which has very high dispersion. Shows AlO, Mg, Ti etc. This is useful for determining the excitation conditions in AlO (what is the application of this information). Comment by Peter on heel / toe of footprint. Toe defined by main lead fragment (but needs to be confirmed), heel defined by solar array fragments (detected in JSC intensified data??) Emissions of atomic elements are only from the gas phase – ie. material which was ablated. Q. T. Lips: Is it possible to look for Colubium/Niobium, these are found in the main engines. This would be an excellent marker for the propulsion compartment. (Note this metal does not have a strong spectra, so it is not easy to detect in data)

Mike Taylor (Utah State Univ. NIRSPEC1 instrument): “Near infrared imaging of the destructive reentry of the ESA “Jules Verne”automated Transfer Vehicle”. See PDF presentation #12 Visible & Near-IR imaging, with spectroscopy. Used Xybion camera’s which are intensified camera’s in the visible range & InGaAs camera’s which work in the 0.9 to 1.6uM range. Prior experience of the team included the Leonid MAC missions & Genesis / Stardust SRC reentries. Performed slitless spectroscopy, including first spectra in near-IR of a meteor. Participated in Aurigid MAC & obtained near-IR spectra. For Stardust did near-IR spectroscopy & obtained balck body radiation, C lines from PICA heatshield material. For the ATV mission Two Xybion camera’s were used with two different focal length lens. The InGaAs camera was used with a Grism (combined prism & grating) operated at 30fps, but with a 1ms exposure which helped in preventing saturation of spectra. Also a conventional HDTV camera was operated, as well as low light guiding camera. The system was configured to permit some flexibility, since there was uncertainty in how the object would appear in the sky. Results: In visible region spectra of fragment train & of head fragment in 2ry spectra were obtained. In the Xybion imaging data lots of faint fragments are visible as gain is increased after passage of main fragment train. Breakup of last main fragment occurred at approximately 51km altitude. Although the main body is over exposed the small fragments are easily detected & tracked. InGaAs spectrum (main lead fragment) – AlO detected in near-IR, time evolution can be followed. Also a strong continuum was detected. After disintegration of last main fragment, there is an object which appears to pull ahead of the main fragment. This has a distinct spectra with emission lines. Spectra have been calibrated. Two bands detected 673.6nm & 773.4nm, this indicates Li & K, which is suggestive of a battery. This is also a transient release. Interestingly there is almost no sodium . Comment from audience: Where is Li is used? Batteries, perhaps some instruments. A large Ni/Cd battery was included in the download cargo Comment from Marek Kozubal: It would be useful to know what is the anode of the battery, since these often have many trace metals which could confirm the presence of a battery in the fragment. Comment from audience: What is the minimum concentration of materials need to be detected in spectra. A. from Peter Jenniskens. In principle this could be calculated, but requires some calibration for brightness.

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Faint fragments detected for 50s after passage of main fragment. Some fragments can be followed for some time. A bright object is seen in the Xybion data, it is still unclear whether this is a part of ATV or a satellite. This needs to be confirmed by trajectory analysis & cross check with satellite catalogue (if it is ATV, perhaps it could be the docking adaptor). ISS is seen later. Lots of spectra (~40,000 images) therefore need input from ESA on which aspects to focus. Comment from Hans Nielsen: Identification of late bright object seen during aircraft turn – will perform a quick cross check to see if this could be part of ATV (eg. docking adaptor).

Ricarda Wernitz: (IRS, Stuttgart: SLIT spectroscope team). “ATV-1 Jules Verne airborne observation campaign: SLIT”. See PDF presentation #13 This instrument was operated on the DC-8 through an optical window. The spectrometer is a slit setup, this is coaligned with a videocamera and telephotolens. The FOV of the fibreoptic cable that connects to the spectrograph only has a FOV of 0.45degrees. The CCD system uses a fibreoptic bundle which connects which integrates over all bundles, these are then binned vertically. Video presented which shows time evolution of spectra compared to video.After passage of main body some brief spectra of fragments detected. Data evaluation: Some limitations due to narrow field of view & 700ms exposure time may result in some mixing of fragments. Approximately 200 spectra obtained. Good coverage of most of reentry, including the explosion events. Detected Al, CN, K, Ca & Na. Some simulation of molecular radiation performed, expect to see CN & N2+ emission. Explosion assessment: 13:35:56, see Na, Al & perhaps Ca+. Molecular radation from N2+, background not understood. Weak signal detected which is expected to be OH which is strongly adsorbed by atmosphere, therefore important to compare with ISS data. Main explosion: 13:36:19 See Ca, Al, K? & a strong unknown peak. Exposure is 700ms, so the 13:36:19 & 13:36:20 overlap the explosion. Need to cross check exposure times with actual explosion time (starts at 19.08s, reaches maximum at 19.18s) Fragment spectra at 13:37:31. So far have identified several species. Emission from N2+ seems weak Comment: Peter Jenniskens: Strong peak at 384nm, this might be magnesium. Comment: Mike Winter 13:37:18 spectra – some strong bands at 336nm, this could be NH??? if so this could be indicative of the missing fuel?

Michael Winter (UC Santa Cruz/ Ecole Centrale Paris; FROG instrument PI) “Multiband imaging photometry of the Jules Verne Reentry with FROG”. See PDF presentation #15 The principle of the FROG instrument was narrow band imaging with rotating filter wheel. Filters for H- alpha, O, Al, CN, N2+, Al, and CH were used. The spinning filter wheel required a synchronisation of rotation with CCD camera frequency. The system was used in combination with a grating. The spectrum turns into a line due to rotation of wheel. Due to limitations of the data storage device, it was only possible to collect data during a minute at time, followed by 45s data download. The explosion missed since the object moved outside the field of view. Following reaquisition the object was heavily saturated. Results: Strong scattering in O, is this indicative of real fluctuations. Strong peak for Al for one of the flames Comment: Jim Albers – do you see fluctuations in intensity with stars which pass through field of view. Mike Winter: Will check this.

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For H-alpha, there appears to be no real H-alpha emission, since background (wide band filter) has almost the same intensity. There is a strong peak for Aluminium at 13:36:02 this corresponds to one bright flare prior to the explosion. Filtered data has been subject to some image analysis, some fragments show up in some filters & not in others. This potentially allows identification of materials. Some show strong Al signals, others show only strong O emission. Spectra were quite faint prior to explosion, only 3 spectra visible. There was some variability in the filter wheel rotation, only when the wheel slowed is the exposure strong enough. After explosion there are good spectra signal, which are not saturated. Calibration being performed. Start of second order spectrum also recorded. Spectra recorded from 350nm-700nm, second order spectra starts to overlap beyond 700nm. There appears to be an underlying continuum, this should be from solid objects & so could give surface temperature of objects. Data analysis is ongoing, most analysis only performed prior to explosion.

Ron Dantowitz / Marek Kozubal (Clay Center Observatory, NIRSPEC 2 Team). “NIRSPEC2 and VIS-SPEC Instrument results: Fragment composition and identification”. See PDF presentation #14 Ron Dantowitz made the presentation via iLINC/Telecon with Marek Kozubal providing support directly in the meeting: The NIRSPEC2/VIS-SPEC instrument. includes conventional coaligned 12bit cameras that can run at 60fps, plus an InGaAs operating in the 0.9 to 1.7um range. The instrument was setup to have coaligned overlapping spectra from 0.4 to 1.7uM at 30fps. Objective was to do high temporal & spectra resolution, including looking at time evolution of spectra. with the goal to identify fragments. Visible range spectral resolution was 0.24nm/pixel. Main instrument on GV, one visible instrument on DC-8. A zero compression recording system was used to record 14bit data at 30fps. Data showed emission lines & continuum. Initial observation, three main fragments – top fragment does not have Ti, trailing fragment is very rich. Each spectra changed with time, sometimes evolving within a second. Integrated data with time. Analysis of fragments with time allows spectral tomography = look at different side of same fragment as it tumbles. The instrument recorded spectra of explosions!!! There were very rapid changes in spectra at time of explosions. Lots of lines appear. This was seen before and after many flashes & explosions. These last only a few milliseconds. Main explosion recorded. This was bright, but did not saturate, multiple lines seen. Some preliminary identification of lines, including telluric oxygen absorption, K, O. Also see material streaming out of ATV at time of explosion (need to confirm this is not 2nd order). Also an expanding shell of material detected after explosion, it is not clear if this is an emission from a cloud or reflection on the cloud from the main explosion. Once fragments separate along track it is possible to get individual spectra for each fragment. On slide 12, front fragment (at left on image) lacks Titanium but has a lot of Mg, 2nd piece has no Chromium, three piece has lots of Chromium & AlO bands. Fragment 4 (bottom) has a lot of Titanium – a tomographic image (to see different sides of the same fragment) was constructed, which had a lot Titanium, with a lot Chromium & magnesium. Tumbling was easily recorded in spectra, since the object was not saturated. Detailed spectral analysis performed showing lots of materials. Cross referenced data to imaging data, resolution is sufficient to allow certainty in identification of individual fragments.

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Tomographic data from lead fragment shortly after explosion. A strong lithium line appears transiently. Sodium, Mg & Aluminium are seen. Object darkens significantly shortly after end of Lithium signal, then a fragment detaches from the lead fragment, which takes the Lithium with it. Comment: Mike Steinkopf – checked waste manifest. Found a russian battery of 75kg in ICC (pressurized compartment). Identity of battery unknown (Lithium or Nickel.Cadmium), but size suggest that this should be a Nickel-Cadmium battery. ATV has 4 Li batteries of approx 18kg in the interstage area which are non rechargable. 4x Nickel-Cadmium batteries of approx 70kg which are rechargeable. Only source of Li onboard the spacecraft are the 4 ATV Li batteries. From tomography data it is possible to graph the time evolution of each element / molecule seen in the spectra. 4th object has a spectra that changes every 1/30s (rapid tumbling) changes from Ti to Cr, then Mg & back again. Li release at 13:36:23 – data has high signal to noise ratio at 12bit. also since the recording is a video frame rate it is possible to see exact moment Li is released. This occurs almost instantounsly. Possible to also do ratio of each chemical species. For the Li signal, chaotic tumbling can be seen. Prior to main explosion, a large flare of Mg is seen – time course shown for Mg, Na & Li. A continuum is also seen. Additionally, it was seen that Mg is seen first, then Li release as the object tumbles. This suggest that the Li source was attached to a Mg structure, until it breaks loose. In trail a number of point sources of pure Li are seen in spectra. These can also be seen in the HDTV video. {Li release initial from fragment #1, then goes over to fragment #2} Mg/Na ratio has some perioidicity Release of yellow gas from one fragment (#2) = 565nm line emission & broad band down to 50nm shorter frequency with several emission lines (about 10 lines). Also see material streaming from fragments, see a point source with Li. Last fragment released from final main fragment (#1) – has a very strong Li signal, this is therefore one final battery, which was probably sheltered during the reentry. Difference in release of Li probably as a result of different release times of individual batteries. Spectral lines also seen in InGaAs spectra. 3-D animation of HDTV video available can also be performed by this team.

Chris Kitting (Cal State Univ. Long focal length imaging): “Project SCOPE on NASA mission ATV-1 MAC”. See PDF presentation #16 The objective of instrument was to image long focal length imaging of trailing fragments. Did an initial test of imaging system by imaging ISS, resolved ATV attached to ISS in July 2008. Imaging setup was on DC- 8 looking through a standard window. Aircraft window had inner pane removed to improve view & also polished windows. Camera was used with a grating, as a slitless spectrograph. Calibrations were made on the Moon and Jupiter, with the zero order & first order spectra visible simultaneously. Aircraft window introduced significant aberrations to the image. Diffraction of object by window was approx 50”, so limiting factor was window quality. May have made earliest detection of ATV from DC-8 with tracking camera on horizon. Some stacking & image processing used to attempt to improve signal to noise, but did not improve resolution of image. DSLR images taken of fragments & main body. Attempted some sharpening of the object in processing. Exposures ½ to 1/8s Attempted stacking & deconvolution. Image shape is elongated – is this a real shape??, assumed that this was resulting from aberration in the image. Image is 3 x 6’, rather than the actual object it might be the ionisation cloud. Persistent trail was not detected.

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Comment from Ron Dantowitz: At the time of this image, the vehicle had already fragmented so what should have been visible would be a fragment cloud. Attempted bioluminescence imaging of ocean using image intensifier, for 20’after reentry to see if major impact created a glow in the ocean. However, clouds over ocean blocked view of sea surface.

Detlef Koschny (ESA, D/SRE) “ATV in infrasound?” See PDF presentation #17 Collaboration with KNMI (Läslo Evers) for infrasound measurements. The principle of the system is to pick up high frequency sound, used to detect bolides. For ATV reentry the atmosphere state was not favourable for propagation of infrasound signature. Therefore, there was no detection of any signal from the ATV reentry. Atmosphere state prevented any of the sound reaching the ground. Update on SPOSH presentation from yesterday – incorporated refraction model into astrometric measurements. Now this is much closer to the reference trajectory. . Small shift in the ground track, which might be the conversion error.

Roundtable discussion: spectroscopy. open discussion on spectroscopy data. Jean-Carlo – Magnesium in Russian provided compartment, this is part of the docking assembly. This would be attached to the ICC (pressurised compartment). Other sources of Mg Main S/C structure ICC - = 2219 alloy, Cu 6.3%, Fe, Ti 15%. Remainder is aluminium Mg can be in 2224 alloy, 1.6% Mg. Lithium Alloys not used in S/C since these are brittle. To identify materials in main fragments there is a clear need to have input from ESA of the material list. Mike Steinkopf – presents waste manifest list. Confirmed that Russian waste battery is a Nickel-Cadmium battery (block 800 battery, consisting of 22 cells). This is an electrical component of the RS-ISS, mass is 75kg. Does not contain any liquid components, has an aluminium case. Also this object is discharged prior to download. Downloaded mass of waste – 264kg of Urine in 2 tanks Dry cargo – 816.4kg No refuelling & propuslsive support left remaining Total integrated dry cargo including racks, shelves etc = 2115.6kg Mass at reentry = 12718kg (+/-131kg) basesd on telemetry. Remaining mass of propellant = 867kg (+/- 87kg) for PRSS+29kg ATV project/CC is interested in history of breakup & fragmentation. Also estimate how much survived to the surface? Need this in a summarised version – i.e. identify fragments, then cross correlate to identified fragments. Explosion – we see a very obvious event that disrupts the entire vehicle, yet there are no obvious signatures in the spectroscopy (N,H,O,C etc). Ron Dantowitz has spectra of explosion, many lines visible. Also interesting events before & after flash. Q. from Jim Albers – what coatings or paints are present on the spacecraft??? The Aluminium components are anodised, perhaps this could provide trace elements in spectra? Quick analysis of Dantowitz spectra of explosion shows no H in explosion. Is there any possibility that H emission could be quenched or hidden – A. from Peter Jenniskens – No, if H is present then it should be seen. Hans Nielsen, questions whether H would be detected at this altitude. Peter – this was seen in

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Stardust, but the entry speed was fast. CN is detected, but this appears to come from the MLI since it is seen continuously. I.D. of fragments: Engine has inconel which has lots of Chromium. Docking adaptor has Titanium.

Wednesday 11th February

Christina Giannopapa (ESA, TEC-MMG); “High speed imaging of fragmentation events and tumbling: image extraction and analysis”. See PDF presentation #18-1 ESA High frame rate imager. Two systems flown. “Teras”camera system could operate simulatously 3 cameras’for up to 20 minutes at 500fps. This system was installed in the DC-8 because of power & weight capabilities. The fastcam system had a limited recording capacity, but was adapted to run from a laptop. This system was run on the Gulfstream V. Both systems observed the reentry. Good data from the Tera’s system on fragmentation events. New high framerate camera being developed. Bas van der Linden (Eindhoven University of Technology): “Automated Fragment Extraction and Trajectory from Images”. See PDF presentation #18-2 Development of an algorithm for automatically detecting & tracking particles. Presented video & stills from each camera. Fastcam showed light curve of explosion. Tera’s shows tumbling of main fragments & small fragments tumbling in wake. Flashes are well recorded & tumbling. Lots of frames of Li rich lead fragment after separation can be followed for many fragments. Since the camera runs at 100fps, it is possible to follow high frequency tumbling (eg. faster than possible with video & Ron Dantowitz 30Hz rate spectroscopy). Comments: Identification of fragments are tentative, it is possible that some objects are inside, which are then released into the fragment stream. Particle detection with software & automatic tracking was developed by the university of Eindhoven. This can be applied to any of the video data. Threshold setting needs to be varied to ensure good tracking and it is sensitive. The algorithm can be extended as multi-scale to fine-tune finding smaller and larger fragments. After the automatic detection a tree like structure can be applied to describe the movement and splitting of identified parts and speeds. Can analysis fragments in time & plot in 3-D which is useful for interpreting timecourse. Comment: Expect only source of potassium would be in some high temperature alloys in the propulsion compartment

Hans Nielsen (Geoff McHarg): “High frame rate spectrometer (HFRS) initial results for ATV-1” High frame rate imaging & spectroscopy. Data shows scintillation of stars at 7-10hz. Therefore, we have to be careful in interpretation of tumble rates at this frequency. Spectra – see Na, Zn? (636nm), unknown at 652nm, 721nm, O- airplasma, 830nm (could be Cl). High altitude spectra Raw frames images are averaged (11 frames) to improve signal to noise ratio. Prior to explosion, there were strong emission lines. Explosion was saturated, but 2nd order spectra is detected. Video’s presented. Light curve of main explosion – rises quite sharply, then slower fade, apparently with steps. Data gives good light curve, but some problems with saturation. DC-8 data detects spectra of explosion cloud, which will help identify material in cloud. First look it appears to have a continuum (eg. could be NO)

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Comments: Peter Jenniskens Explosion cloud has two parts, one part that fades rapidly the other slowly. This maybe provides a clue to the parts of the explosion, with perhaps a different cause for the early part of the explosion (Note this seems to be confirmed by the Gulfstream V HDTV video which shows a rapidly fading glowing patch immediately after the main explosion in the wake).

General Discussion: Jason Hatton: We have lots of data. Good initial analysis, we have an initial triangulated trajectory of reentry for main fragment. Some analysis of relative trajectory of fragments, we have good tools to do this. Spectroscopy provides detailed information processes occurring & materials, data is probably sufficient to identify main fragments. Explosion mechanism is a mystery since there is no signature of fuel, yet is clearly a powerful event. High framerate imaging provides light curve which gives clue to sequence of explosion (multistepped).

Peter Jenniskens: Discussion of events. Early in reentry main body & trailing fragments, suspect these are solar panels. NASA-JSC data may provide information when these separated. After explosion, three main fragments. Last main fragment has high ballistic coefficient (600kg/m2), which then falls aparts. Maybe a final bright fragment which defines the te fragment. Explosion: could this be an oxidiser explosion? Post explosion cloud shape may provide clue to shape of explosion. Are fuel signatures detectible by spectroscopy? We do not know what the spectrum of fuel combustion? Mike Winter suggests that we need to get a spectrum of a thrusters with the same fuel. Peter Jenniskens: Continuum spectra of explosion cloud might be Nitrous Oxide, this would point to involvement with oxidiser. However, this still requires fuel of some sort. Tomasso Sgobba: Believe that tank design results in leakage of tanks, rather than explosion. Therefore, need to compare the observations with physics of tank failure. Tanks were qualified to leak before exploding. However conditions are different inflight to on the ground (eg. higher temperature & pressure). We need to understand the energy involved in the explosion. Can this be calculated from the delta V imparted to fragments at the explosion. Marek Kozubal: Alternative hypothesis for explosion. This could be a “slow” explosion from combustion of aluminium & perhaps magnesium with N2O4 as a result of the oxidiser tank rupturing & ignition of molten aluminium. Spectra is consistent with this, with a large production of AlO at the time of the explosion. Lithium is not released in explosion, this seen shortly afterwards. Immediately after explosion two fragments. Initial Li release from lead fragment (#1), which splits into two fragments. The Li signature follows the second fragment (#2). Fragment #1 perhaps consists of primarily the ICC. Fragment #3 has a small flare, followed by a release of a yellow gas cloud (which has a distinct spectroscopic signature). This probably corresponds to the propulsion compartment Fragment #2 falls apart & releases several Li fragments. This probably corresponds to the interstage area. Docking adaptor may be one bright fragment above the main body. Perhaps this detaches with the upper cone of the ICC giving a lower ballistic coefficient initially until this ablates away. This catches up with the main mass, but is lower & becomes brighter. This could be the bright object seen late in the reentry. This appears to break off shortly after main explosion. Fragment #4 detaches from fragment #3, seems to be associated with propulsion bay.

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JPH: Li seen in both fragment #1 & fragment #2. This suggests an asymmetric separation of interstage area with at least one Li battery staying with fragment #1. Fragment #1 completely disrupts & sheds many small fragments, which may be cargo/waste. Tomasso Sgobba: Why does ICC go ahead of more dense parts of the spacecraft. Are the tentative identifications consistent with the observe spectra? Center of gravity was close to the center of cargo bay, so vehicle would be expected to be stable after some tumbling. Not clear with this c.g. that it would be pointing front forward or backwards. Telemetry data provides best estimate of fuel load at reentry which can be used for c.g. calculations. Q. Does telemetry give clues to solar panel separation. ISS/Fialka data should cover this area very well, but we are still waiting release of data from Russians. We expect this in the next few weeks. An iLINC discussion could be performed for the group at this time to discuss the results.

Koppenwahler – brief presentation of Scarab – How does this relate to the observations obtained during the meeting. Analysis of ATV reentry prior to actual mission, therefore did not duplicate actual conditions of JV mission. Reviewed explosions of launch vehicles. Looked at conditions for autoignition of fuels. Explosion will interact with shock front & alter flow field around the vehicle. Analysed likelihood of explosion, eg. fuel tank leakage or rupture. Developed an explosion model, some uncertainty – how many pieces are generated. This was specifically applied to ATV for various reentry scenario’s. Li batteries are clustered on the same location (TBC). Tanks are interconnected. Model has a materials specific mass budget. ICC is Al alloy. Scarab uses material lists in the model. Suspect some Al-Li alloys might have been used which could explain the weak Li signal. Explosion altitude probability calculated. This took into account when leakage in feed & drain valves might occur. This is as a function of temperature. Threshold set at 600K, since most valve seals would fail by this time. Compared to observed explosion this condition would occur at a lower altitude than observed explosions. Tank filling & burst considered. A full tank acts as heat sink & so takes longer to heat up, whereas a partially filled tank will heat more rapidly. Modelling suggests explosion in the 40-60km altitude range, valves fail at higher temperature. Explosion likelihood increases as altitude decreases. Modelling of fragments following explosion done in a simplified manner compared to main body. Assume entire ATV destroyed in explosion However, observations show that ATV only partially destroyed. Therefore, modelling approach does not match actual event. Nevertheless, the model can be adapted to actual fragments generated. Fragment survival analysis. Did breaking stress analysis for solar arrays, taking into account the tumbling of ATV. It appears breaking can occur at around 95km. Tumbling becomes chaotic below 75km, looses some material then becomes stable at lower altitude. In this particular simulation condition the ATV does not explode & largely remains intact. Can calculate surface temperature of components at each step in reentry. Input data to model for explosion fragmentation comes from in orbit explosions = NASA standard model (evolve model). Conditions during reentry may be different, which is why observational data from JV- MAC campaign is useful to cross check the model. Comment from Hans Nielsen: Sodium emission may actually come from atmosphere (in the mesosphere from 85-100km altitude), so the4 passage of ATV through the atmosphere may excite sodium from the atmosphere. PJ: Meteors often source of Sodium. Fragment naming convention: suggest a family tree naming convention.

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Heinz Waterenberg joined meeting to provide information on spacecraft materials & composition. Peter Jenniskens presented a summary of the working hypothesis of ATV breakup & explosions. Working hypothesis substanciated by spectra of individual spectra. Fragment #1 – has a lot of magnesium Fragment #2 – has Ti & Cr Fragment #3 – has Ti & a lot of Cr.

Magnesium found in all fragments, but is more abundant in Fragment #1. It is known that a lot of Mg is Li batteries. The 4 batteries are distributed over two separate plates. Heinz showed that these are infact on the top of the propulsion compartment. This changes the working hypothesis. The Ni-Cd batteries are on the wall of the interstage. Phase-C/D team input: There are several hundred kg of wiring harness which contain Cu. This is seen in spectra, this is present both at time of explosion & after explosion. Spacecraft consisted of several bolted sub-units, rather than welded. Therefore, these could be weak points for fragmentation. The three main segments are bolted, as well as the subunits of the propulsion compartment. Often these are made of stainless steel or Titanium bolt. Docking adaptor is quite likely to be bright object seen briefly in Mike Taylor’s video during DC-8 turn. If this is the case it is still visible down to perhaps 30-40km altitude. This could also be the bright object seen above the main fragment cloud. Also there is a fragment visible in Julian Nott’s DSLR data where there is a spectrum, which might be the docking adaptor. Niobium is in the engines/thrusters, but it appears that Niobium does not have a strong spectral signature. However, there is a heatshield material to protect the spacecraft which might be ceramic, perhaps this could be a signature. Marek Kozubal presented more detailed analysis of alternative explosive hypothesis. During reentry a lot of molten Al & Mg may be available in propulsion compartment, along with N2O4 oxidizer. Spectral tomography plot covering period leading up to, including & after explosion (8s prior to explosion & a few tens second after). Precursor flare (8s prior) is rich in Mg, but weak Al. Also some Li, which is probably an impurity in the Al alloy. This prexplosion shows several emissions, including Al, AlO, strong Mg, Na, O, Li, K. One suspected O emission seen in explosive events, which may be a highly excited state of oxygen. Key points are Al/Mg rich environment, lots of oxidiser (N2O4, approx 500kg). Main explosion has similar signature to other flare events. A mystery line at 650nm is seen, but O is absent except at flash. AlO emission increases after explosive / flare events. Three unidentified lines appear at time of flare. If these can be identified then this will provide clue to mechanism of explosion. Hypothesis is that N2O4 provides oxidiser for deflagration of molten aluminium/magnesium resulting in explosive event. Excited O line may be associated with N2O4 reaction with Al?? Lots of as yet unidentified events at time of explosion, but major spike of excited O Comment from Mike Winter: Would require a lot of energy to get O in this state, via a chemical reaction. However, it should be possible to see other energy levels as well. Could these be other lines? Think it may be unlikely if this is excited O. Very little C is seen, but this should show up in the near-IR. Need to look at this data (Ron Dantowitz & Mike Winter) Early flares seem to be more associated with Mg release, while later events are associated with Al release.

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All flares have similar light curve – 100ms rise & 600ms fall. This suggests a similar mechanism for these events. Similar emission lines observed in multiple events. Modelling of reaction is also need to verify if model is valid, and also give indication of combustion products. Comment: Koppenwahler – data from ablation would be useful for input into model & correlation with modelling. Comment: Tobias Lips – how much material is required to generate the metal signature observed? Is it possible to calculate the physical amount of material corresponding to the observed signature? Mike Winter – Requires some calculation, but is very sensitive to temperature a small difference can result in several hundred fold difference. Therefore it is not possible to provide an absolute amount, but relative changes are probably proportional to actual amount assuming no large change in temperature. PJ: Conversely for molecular bands it is in principle to get an estimate of absolute amount, since the temperature can be derived from band slope. Peter Jenniskens/Jim Albers – need exotic elements to identify components. Response from ATV project – if we are working with only small components there are many components. For example there is Berylium in the thrusters assembly. This would potentially a good marker for thrusters if these are good spectral emitters. What paints are used on the spacecraft, including paints from Russian components? These might provide useful signatures.

Tetsuya Yamada (ISAS/JSPEC/JAXA) “Overview of Hayabusa return and observations”. See PDF presentation #22 General overview of JAXA organisation. Hayabusa mission is a asteroid sample return mission. Asteroid samples returned in a sample return capsule. Rendevous & sampling performed, but spacecraft contact lost for some time afterwards. Spacecraft control recovered in Feb 2006. As a result return to earth was postponed by 3 years to 13 June 2010. This date should remain confidential. Reentry is during nightime (at midnight!), entry velocity = 12km/s. Spacecraft bus makes a destructive reentry. Landing site is Woomera on a dry lake (Lake Parakylia). Sample return capsule separates heat shield & back shell to deploy parachute. A beacon assists in localisation. Reentry conditions: 12km/s. Capsule High heat flux, up to 12MW/M2, heat shield may reach 3000°C. Heat shield is a carbon phenolic ablator, not Pica. SRC capsule is 40cm in diameter, smaller than Genesis and Stardust SRC’s Spacecraft bus separates at R-3h with a separation velocity of 20cm/s. This results in a 2km distance behind SRC, at 100km distance this results in a 1degree angular distance separation. It is not anticipated that anything will explode, nor material survival to ground. There are some tanks, including Xenon propellant. A key question is which object will be brighter. Altitude, relative track plot presented. Max heat flux expected at 60km altitude. Expected brightness of SRC is -5 astronomical magnitude viewed from front at two ground locations. Two optical observation stations on the ground are planned (Red lake haunted house & contrave 6). Ballistic coefficient of capsule in hypersonic regime is estimated to be 120kg/m2. Comment from PJ. Would place aircraft for airborne observation near 40km altitude point. This would give a good view of the approaching SRC. There would be a potential issue of overlap of the view of the SRC & spacecraft bus. Therefore, maybe it is better to place the aircraft off to one side. Recovery operation strategy presented. There is a strong interest in having airborne observation for capsule tracking, especially in contingency situations to assist in localisation of capsule. Plan to have optical trajectory determination within 1h of

MEETING meeting date ref./réf. page/page 17 date de la réunion 18 reentry. There will be postflight analysis of TPS material & spectroscopy of reentry parameters. Also interested in infrasound analysis. Ground impact with parachute is 7m/s, without parachute 45m/s without parachute & failed separation of heatshield. Outstanding issues for making airborne observations. Need to coordinate with Australian Civil Aviation Safety Authority (CASA). Strong desire from Australian government to keep reentry date/time confidential.. A JAXA/NASA/Australian agreement needs to be setup, a draft has been made. Need a MAC team for observation. Questions: What heat temperature will the heatshield have when it hits the ground. A. It should be relatively cool as a result of convective cooling during descent. However, it should remain sufficiently warm to be potentially located with mid infrared. Peter Jenniskens: Current status of Hayabusa SRC MAC is that there are discussions between NASA & JAXA. There is strong interest in doing this on both sides.

Thursday 12th March 2009

An action Item list was drawn up with remaining analysis and activities to be done in the next few months. See separate action item list

Christina Giannopapa (ESA, TEC-MMG) – “GSP – Assessment of the ATV-1 re-entry campaign for future reentry mission”. See PDF presentation #22. The general objectives of the study were presented and how the study will serve as an interface between an work done by the MAC team in the ESA/NASA agreement and what is needed by ESA to obtain answers that are needed to decide upon future missions and prepare for follow up planned studies for GSP and GSTP and possible others that will rise as the current study will progress. The time line of the studies was shown. The GSP study is split in three parts. The most important part and it is expected to take up the biggest part of the study is the data analysis and trajectory reconstruction (Task 2). The contractor is expected to reconstruct time tagged three dimensional trajectories of all identified fragments and characterised them as much as possible. The data observed should be compared with the previous model studies. This should be done only as ‘paper report’ comparison no new runs of models are expected. In this study an evaluation of the mission is also expected and evaluation of future possible missions. From this study it is expected that the ‘What happened during the ATV re-entry?’ question will be answered better. It is expected that a list of fragments and their 3D trajectories will be obtained and the data set could be saved and be used for future use. A first estimate of what was expected and what happened via the model comparison will be given. Requirements and recommendations for future missions will be extracted from the ATV MAC mission. The needed background as expected to complete the study was explained. This background is versatile and requires knowledge from different field. Cooperation with the Principal Investigators (PI) that participated in the study is encouraged. It is essential for ESA to have all necessary questions answered by October to make further decisions. This was clearly communicated that the time schedule of this study is very important. Comments: Koppenwahler – very challenging to do. Need to get a good cooperation between team members. The PIs can be included as part of the bidding consortium and with the restriction that the USA participants can participate for a maximum of 10-15% of the total value of the study. Comments: The communication link between the PIs and the Contractor is complicated.

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Comments: If the PIs are included in the study as part of the consortium then this will ease communications and the PIs will be willing to participate and cooperate more with the contractor. Comments: The publication issues is sensitive? How will publication rights be ensured? The contractor will be able to publish togethere with the PIs papers. Publications with co-authoring with the PIs in encouraged within the GSP study.

Wrap up – Peter Jenniskens. Final meeting, in September 2009? Possibly at NASA-JSC. to proceed Manchester meeting. However, two separate meetings may be redundant. Also aim to have papers ready in this time frame. PJ/JPH as guest editors Presented simultaneous video of HDTV video’s prepared by Marek Kozubal. Suggested that this video could be annoted with fragment numbers & items. This could be compared with other video’s. Suggest to setup a simultaneous annoted video, with the two HDTV video from both planes, plus an intensified video from each aircraft.