It’s been quite a historic day here on ISS: the last of the Automated Transfer Vehicles of the European Space Agency, ATV-5 George Lemaitre, has just departed and is now safely separated from the Station, on track for a destructive reentry into the atmosphere tomorrow: it’s taking away tons of waste and discarded items, thus giving us quite a relief on ISS in terms stowage space.
But we’ll have time to talk about the departure of ATV and all the pre-departure ops in a future logbook, today let’s go back a few days and look at the departure of another vehicle earlier this week: Dragon! Last weekend was really busy here on Station as we got the last things ready to be loaded. I wrapped up the “Epigenetics” experiment on Saturday, fixating the last generation of our C. Elegans worms for return to Earth. Scientists on the ground took a look at the culture bags in the camera and reported that, judging from the color, the worms had been growing just fine, so hopefully there’s now three generations of space-born C.Elegans on Earth.
The weekend was also the time to reinstall in Dragon a number of cold-stowage facilities, called Polar and Glacier: these moveable fridges fly up and down powered by the Dragon power supply, but in between they are actually installed on Station. Moving them is quite time-critical, because we don’t want them to remain unpowered for more than 30 minutes, so Terry and I worked together on a timed choreography that allowed us to operate in parallel, minimizing power-off time.
Last but not least, there was a last-minute entry on our timeline on Sunday morning: the removal of a fan-pump-separator (FPS) on a EMU, the suit for spacewalks. In Logbook L+16,L+17 I have told you about the FPS, since Butch and I replaced one back in December. Unfortunately, the FPS has failed on another suit. We don’t currently have spares onboard, but it was decided that the failed one should be removed and returned on Dragon for analysis on the ground. Doing it the second time was not as daunting as the first time, especially since we did not install a new one, but it was still a challenging task to remove all the hard-to-reach, non-captive screws and washers! We were glad when we were done and could hand it over to Terry, so he could properly pack it for return.
Talking about packing, that was the big task for Monday. In the morning it was cold-stowage ops again, as Terry and I packed and loaded six cold bags with samples from our MELFI freezers. Cold bags are like coolers with a very thick insulation, in which samples for return are stowed together with cold bricks to keep them cool until they can be retrieved on Earth and put in an actual freezer again. For each cold bags we had diagrams which showed exactly how they had to be packed and, in some cases, in what precise orientation.
Unfortunately, that’s one of those things that works a lot better with the help of gravity, because up here there’s nothing to keep all those items where you put them, until of course the bag is full and the lid will press everything in place. Also, as you can imagine, packing cold bags is necessarily a last minute operation: we packed them on Monday morning and on Monday afternoon we closed the Dragon hatch. Terry and Butch then installed the controllers for the motors that drive the bolts keeping Dragon attached to ISS while I, In the meantime, took a trip to ATV to install the Break-Up Camera, which will actually observe the breakup of ATV from inside tomorrow!
Tuesday, of course, was release day. After a successful leak check of the hatches, making sure that neither Dragon nor ISS would have a leak when demated, Butch drove out the bolts, disconnecting Dragon from us, and then controllers on the ground started to fly the robotic arm to move Dragon to the release position.
In the early evening, Terry and I were ready at the robotic workstation in the Cupola to perform the release and send Dragon on its way home. At the release time, I ungrappled it and backed away the arm to a safe distance of about 4,5 meters. At that point, Terry sent the Depart command and Dragon performed its first burn, commencing a slow but clearly visible separation from ISS. Really strange to see it go, after having had it as our neighbor here in Node 2 for several weeks. But hey, we’ll get another one soon!
Futura mission website (Italian): Avamposto42
avamposto42.esa.int
(Trad IT) Traduzione in italiano a cura di +AstronautiNEWS qui:
https://www.astronautinews.it/tag/logbook
(Trad FR) Traduction en français par +Anne Cpamoa ici: https://spacetux.org/cpamoa/category/traductions/logbook-samantha
(Trad ES) Tradducción en español por +Carlos Lallana Borobio aqui: https://laesteladegagarin.blogspot.com.es/search/label/SamLogBook
(Trad DE) Deutsch von https://www.logbuch-iss.de
14/02/2015