• ANITA-I Antarctic Travel Log

    by  • November 1, 2006 • Travel Log

    November 1-15, 2006

    The initial ANITA team arrived the first week of November, and the gondola build was in full swing by the 2nd week, and nearing completion at the end of that week. The major efforts have been focused on painting & silver -taping for thermal control, and starting the channel calibrations which will reflect the final configuration of the instrument. The weather has been very nice. There were some glitches with the new payload building, but we are assured it is much better than last year. Still no indoor plumbing though…

    November 19, 2006

    We have nearly completed all the major channel calibrations, including noise figure, system overall gain, and a complete map of the group delays of all channels. The latter measurements are almost done, with just a portion of the bicone/discones remaining.

    All of the structure is in place, with the exception of some of the deck tensioners and the deck-to-tier3 guys. Sensors are all mounted and cabled. Bicones and discones are not yet mounted pending the completion of cable calibrations. The CSBF SIP is mounted and LOS cabling is in place, but we have not yet started transmitting local LOS data.

    We are scheduled for an outdoor calibration excercise this coming Teusday, two days from now, to perform GPS calibration, and take sunsensor, magnetometer, and some RF data. Drillers have completed the primary transmitter borehole about 70 yards south of our payload hangar, and a Scott tent has been placed over it, and cabling strung out to it. We hope to test borehole-to-payload transmission on Teusday. A second hole has been drilled 10m away to facilitate antenna calibration, and another hole at 80m distance in planned. The holes are currently about 25 m deep, which is as far as we can go without hitting a saline layer.

    We understand that the ITASE team at Taylor Dome is on site, and we have heard from the PI of ITASE that they are fairly confident the 100m hole will be drilled there. We have also requested that the bottom core at 100m (1m length) be preserved for later testing (the cores are being taken, but they are sliced and melted in normal glaciological analysis).

    Weather has been unsettled in McMurdo, with light snow the last few days, and some low visibility periods along with moderate drifting of snow. Weather briefings will begin next week.

    On the lighter side, we had a local contest among McMurdo-ites for art work to paint the battery box for thermal control, and we received some excellent entries. The themes were: a hula girl (for the Hawaii group), an Antarctic theme, and an ANITA science theme. You can see the results at: http://www.phys.hawaii.edu/~gorham/ANITA/ANITA_art/

    November 21, 2006

    Today we had our first outdoor calibration test, with the complete ANITA flight system. We learned a couple of days ago that a TDRSS telemetry pass was scheduled, but in the rush to prepare the payload, we failed to inform those outside of MCM–thus the panicked effort today to get all of the databases and telemetry transfers up and running. In the future we will try to do a better job of coordination.

    We had a successful rollout overall, with most systems working very well, and a few glitches, not unexpected for the first system test since July. Marty Olevitch and Ped responded to our late requests for TDRSS support and database activation, and we did get telemetry through the system in spite of the lack of warning–a good indicator that we are well on the way.

    The gondola and structure performed very well and was easily managed by the BOSS, and in the RF and trigger system we did see pulses from the UCLA system, though we still have to sort out the GPS trigger timing.

    November 23, 2006

    The ANITA gondola and instrument are fully assembled, and calibrations of all instrumental group delays, noise figures, and gains for all channels are now complete, along with a complete set of measurements of the channel impulse response. Two days ago we had our first rollout, and got most systems working for the first time as a complete payload, along with TDRSS and LOS telemetry (including our Palestine, Texas downlink receivers). We also now have several local 25 m boreholes to use for under-ice -to payload calibration pulses, those will be exercised soon.

    Today we attempted another rollout, and after 10 min on the pad, the wind picked up dramatically and we had to come back in quickly. Within 5 minutes it went from a balmy beautiful day, to 25 kts of wind and snow blowing, and now its probably 30kts+. Still beautiful, but not for ballooning!

    Only in Antarctica!

    ANITA in the Willy Field LDB Hangar, ready to roll…

    On deck, waiting for the BOSS launch vehicle to pick us up…

    ANITA on the BOSS vehicle moving out to the test pad, Erebus in the background…

    And again, now approaching the pad.

    The test pad area, along with a Scott tent covering the borehole. A nice day, until about 10 minutes later…

    November 24, 2006

    Today two of the ANITA art contest winners, Kai Smart and Dana Grant, visited Willy to work on their thermal control artwork, and made wonderful progress. ANITA will surely be the envy of all of the payloads down here when our awesome battery box is done. If you haven’t checked out the winning entries, take a look here.

    Good progress was made in repair of some glitchy software/formware modes, and at the end of the day today, ANITA was purring along detecting ratty impulses from the NASA/CSBF Support Instrument Package (SIP), the control system that flies along with us, and does not have its EMI shielding in place yet.

    We are now scheduled to do our final “hang test” before being declared launch ready sometime late this coming week.

    November 27, 2006

    Today ANITA completed an all-day outdoor run on our “pad”–a platform about 200′ from our hangar, with a clear view of the calibration antennas, as well as the local borehole antenna, which goes down about 25m. The run was very successful, with a nice set of data taken for sunsensors and other orientation systems. We were also able to see nice pulses from the borehole antenna in this case only 70m away from the payload), and the levels appear to be adequate for us to detect it out to at least 150km or more once we launch.

    Also today, the Taylor Dome calibration team met with their mountaineer in preparation for departure later this week. The 100m deep Taylor borehole has apparently been drilled, though weather at TD has been very cold and has hampered progress for the ITASE traverse. Based on the early results with our test borehole here at Willy, the Taylor Dome pulser should be easily visible for the 1st day of the flight.

    Christian Miki (in shorts), and Andrew Romero-Wolf try to keep their balance on the payload pad…

    December 1, 2006

    As of last night ANITA completed its task list for readiness for the hang test. The test itself has been delayed a couple of days due to unsettled weather. The payload is in excellent shape, and looks ridiculously tall with the addition of the solar panels to the base, done last night as a final fit check.

    Paul Dowkontt & David Goldstein inspect the ANITA solar panels.

    The payload system and instrument have now had a complete checkout along with satellite telemetry, full calibration of impulse response, group delays for each channel, noise figure for all the receivers, and a lot of software exercising and final debugging of remaining SW issues. We have also been “torture testing” with the high levels of electromagnetic interference in the payload building–we are sensitive to pW levels on orbit, but even running with 32 dB attenuators on everything we are still getting blasted by rf noise. Thankfully we don’t expect it to follow us up after launch…

    Our “thermal art” battery box is now nearly complete as well:

    These are the two winning panels, both with a Hawaiian theme in honor of the lead institution (UH Manoa): Kai Smart’s lead 1st place panel on the right (there is another around the corner) and Dana Grant’s very close 2nd place, which says in Hawaiian “The stars are the spies of heaven”.

    McMurdo culture evolves rapidly, kind of like fruit-fly genetics. The local folks have already managed create a new form of recycling, probably the first of its kind anywhere in the world:

    December 12, 2006

    The last two weeks have been a big challenge for the local team. We finished our hang test and declared flight ready the 2nd of December. After that the waiting period began, as the stratospheric high pressure system had not yet set up over the pole, and there was no planned launch until things appeared more stable. We continued system checkout and tuning of the event prioritizer, which determines the order of events that are telemetered.

    On Teusday Dec. 5, a pathfinder balloon launch was scheduled and completed shortly after 9am local time. However, the onboard GPS tracking system malfunctioned and thus the only option was for satellite triangulation of the iridium signal, which allowed for latitude and longitude fixes but no altitude. In spite of this, the delayed iridium tracking information helped us to learn that the pathfinder did show the proper westerly trend, and this gave confidence that we were entering a period where the high was setting up sufficiently to allow for launches. On Dec. 7 a second pathfinder was launched, but even prior to that pathfinder launch, the decision was made to make a “show” for a launch attempt for ANITA the following day, Dec. 8, with a 1600 launch target time. The launch sequence went well, but marginal surface winds to the south caused a scrub of this first attempt.

    Christian Miki’s shot of the payload on the pad, ready and waiting…

    The next day, Dec. 9, another launch attempt was made earlier in the day, with a 1330 launch target , but this was also scrubbed due to a quick rise in surface winds at about noon, combined with some problems with the CSBF Universal Terminate Package (UTP) having an electrical conflict with the analog readout of the ANITA science stack. After the scrub, we spent the rest of the day debugging this problem, which was subtle but also serious. It was eventually traced to a problem in the isolation of the two signals as they entered the SIP, and we elected to solve it by cutting the analog receive lines from the ANITA science stack, which removes our ability to directly monitor the PV voltages and currents at any time when we are not up and running. Since this system was not really necessary, but more of a backup to our mains, it was not a serious loss in any case.

    On Dec. 10, we made another show at 0530, but conditions were not good enough for a rollout. Overnight tests of the fix to the UTP dropouts showed that it was rock-solid however, and the flight systems performed very well.

    Yesterday, Dec. 11, we had a 0430 show, with a 0645 pickup for ANITA. The rollout went very well, and we were on the pad early, but although surface winds were light, the pi-balls that CSBF flew showed stronger low-level winds that made a launch impossible, and we scrubbed again in late morning. Flight systems again performed very well.

    So today, on Dec. 12, we have showed four times, and rolled out three times– a lot of work with nothing yet to show for it, except a bit more polish on our launch sequence. We are all pretty wiped out, but tomorrow we have a 3am show again, with a 5am pickup! We are not complaining though, everybody is still game for a real launch!

    December 15, 2006: ANITA LAUNCHED!

    This morning we showed at 0600. There was a lot of skepticism initially, since we had shown and rolled out so many times already. Winds were light, but some ominous clouds showed in the south. However, they held off, and surface winds stayed light. At about 0815, we made the decision to roll out onto the pad. The launch preparations were smooth, and finally at about 1340 we launched into high-level cloudy skies. The launch was picture-perfect, about the best any of us had ever seen. The release was so gentle it was hard to really tell the moment when the BOSS vehicle let go of ANITA. There was no panic, just smooth, perfect operation–and a lot of hooting (we could hear it clearly from 800 ft away) from the BOSS operators after the release! They knew they had nailed it perfectly. Congratulations to Vic Davison the launch manager who engineered it so well.

    Telemetry has been smooth and steady and data has been flowing well for the first 8 hours after launch. There is a lot of interference in the vicinity of McMurdo, so we have not yet been able to open up the trigger system–we just get snowed by interference. The payload is about 150km south of us right now, moving slowly southwest at 5-6kt. The only system glitch so far is that one of our GPS units is not responding to queries for position or altitude, but we have a second unit that is performing fine so this is not a big problem.

    Here is a sequence of photos of the launch, low resolution because of the low bandwidth heading out of Antarctica. Contrast was also low because of the cloud cover.