ATV Georges Lemaître has delivered its 100 kg of oxygen to the International Space Station as reported via the ATV Control Centre during the first, second and third transfer from ATV-5's tanks to the Station. After questions on Facebook the team at ATV Control Centre even took time to explain how the amount of oxygen released is calculated.
But how does an oxygen transfer work for the astronauts on the International Space Station? ATV-5 loadmaster and ESA astronaut Alexander filmed the process from his weightless abode for our viewing pleasure:
International Space Station in 2011 with ATV-2. Credits: ESA/NASA
An update from Jean-Michel Bois, head of ESA's mission team at ATV Control Centre, on today's debris avoidance:
This evening the ATV Control Centre performed the first-ever International Space Station Predetermined Debris Avoidance Manoeuvre (PDAM) using ATV Georges Lemaître to boost the orbiting science complex 0.5 m/s at 17:42 GMT (18:42 CET).
The objective was to avoid an object – 34881 (COSMOS 2251 debris) – set to cross the Space Station's orbit at 20:13 GMT (21:13 CET). The slight change in the Station's orbit due to the undocking of the Progress 51P this morning was not enough to avoid the debris.
The PDAM time computation did not put the Space Station in a risky situation with respect to other debris (in particular, object 31289 from FENGYUN 1C, that is passing close but that was not critical in the Station's initial orbit).
A PDAM procedure was initiated by the Station's international community in 2012 in response to a late detection of debris - just 6 hours before conjunction!
A PDAM activates a predefined manoeuvre with a unique boost value. This 'coarse' manoeuvre is enough to avoid a specific debris object and avoids the long computations necessary to define a tuned trajectory and boost value. The previous PDAM used the Russian Progress cargo vessel thrusters, but since ATV-4, ATV-CC can do the procedure as well.
This manoeuvre demonstrates again the reliability of ATV and the skill of the joint ESA/CNES ATV operations teams. ATVs have delivered all services they were designed for over the course of their five missions.
The Laser Infra-Red Imaging Sensors (LIRIS) demonstration, developed by Airbus for ESA tested new rendezvous sensors during a special flyunder manoeuvre 8 August, four days before ATV Georges Lemaître docked with the International Space Station.
The LIRIS sensors were activated during ATV-5's mission and monitored at the ATV Control Cetnre with experts on the LIRIS team confirming that the sensors were working correctly.
LIRIS team at ATV-CC after docking and switch-off (Credits: ESA)
The data from LIRIS was not used by Georges Lemaître itself nor sent to ground control straight away as a large amount of data was generated. Instead data was saved on dedicated recorders. ATV-5 relied on the usual optical sensors (videometers and telegoniometers) for navigation to achieve a perfect docking with the International Space Station - an accuracy of less than 5 mm!
We have mentioned the 'new-car smell' of a fresh Automated Transfer Vehicle before, but never wondered how long it takes for it to dissapear. ESA astronaut Alexander Gerst and ATV Georges Lemaître loadmaster provides the answer in this tweet:
Both @astro_reid and I recently noticed that #ATV5 has finally traded the scent of a brand new space ship for a neutral #ISS scent
This 3-minute video shows excerpts of how ESA astronaut Alexander Gerst and Roscosmos cosmonaut Sasha Skvortsov monitored the docking of ATV Georges Lemaître with the International Space Station on August 12.
An ATV docking is a mix of high-tech and low-tech. Lasers on ATV Georges Lemaître give extremely accurate distance readings but these readings are double-checked by Alexander and Sasha using a simple ruler placed over the monitoring screen.
Speaking in Russian, you should hear the astronauts say “Системы в норме” and “Мишень внорме” meaning “all systems are nominal” and “target is nominal” (this editor's Russian is admittedly not spaceflight-worthy).
After docking the two largest spacecraft around, Alexander has time to record a quick soundbite before a well-deserved congratulatory hug with Sasha.
Impression of Station flying in XVV normal attitude, seen from ATV or moving away from the viewer.
Charlotte Beskow update on ATV-5's important task for today's spacewalk:
Today on the International Space Station Barry Wilmore and Reid Wiseman will change out a sequential shunt unit during a spacewalk (EVA28). NASA TV will show it a bit later, once it gets underway . It is extra nice for the ATV team since Barry Wilmore worked on the ATV project during its development phase a few years ago.
Normally the Space Station flies in what we call XVV where the velocity is along the X axis (ie the axis that runs right along the Station's body) from ATV-5 in the back to Node 2 in the front and with the truss with the massive Solar Arrays sticking out on both sides. For this spacewalk, the International Space Station will change to fly sideways, in a –YVV, ie the truss will be in line with the ground path. To v isualise it you can walk forward with arms outstretched, then turn 90 degrees to your right while still moving in the same direction so your left hand leads. ATV-5 make this attitude change happen and for that reason we all got up very early this morning as operations started around 5:00 GMT.
Astronomer-photographer extraordinaire Thierry Legault has featured before on this blog, but wanted to take images of the International Space Station with ATV Georges Lemaître visible. Taken from a Paris suburb in France, the results are outstanding. Click on "read more" for more pictures and even a high-definition video of the Station passing the Sun in real time (it lasts 0.7 seconds).
ATV-5 solar panels blocking ESA astronaut Alexander Gerst's sunlight. Credits: ESA/NASA
From Eric Conquet at ATV Control Centre:
Today the scheduled reboost has been successfully performed. Ignition of ATV thrusters #1 and #3 was commanded at 09:13 GMT by the Russian Service Module. A delta-v of 1.22 m/s was measured after the manoeuver, just as targeted when planning the manoeuver.
Good job ATV!!