Day off. The week flew by. I requested dynamics for experiments with the PSN, EFO equipment, and for filming the refraction of the setting Sun with the film camera, otherwise the ground conserves fuel and we have to catch moments in free drift for this work. And that’s not so simple. The station has to be facing the horizon with exactly the porthole on which the instrument is mounted, so that the Sun or stars fall within its field of view, and so that during filming they don’t drift to the edge of the porthole where they can’t be tracked by the instrument, since the station drifts with residual angular rates of up to 0.1 degrees per second. So it doesn’t always work out to finish what you planned. But life teaches you to work your way out of any situation, and we adapted to damping these residual rates without expending fuel, using a completely different method — venting air from the airlock chambers, of which we have two along the perimeter of the work compartment’s large diameter. We got the hang of it, and it worked. Admittedly, we’d get absorbed in experiments and forget to equalize the pressure in them with the station afterward, which put Mission Control in a quandary: what’s going on aboard, why does pressure drop in the airlock chambers outside the visibility zone, while in the zone it’s constant. So I wanted to at least perform these filmings calmly on the day off, under normal conditions, with proper orientation.

The ground gave the go-ahead for dynamics for these experiments, but at the same time asked us to evaluate, using the Moon, the deformation of our docked assembly — transport ship plus station — and the alignment accuracy of their sights. For this, at the end of the work, we drove the Moon into the center of the station’s optical sight and observed its position in the transport ship’s optical sight, which is aligned along the same axis. In both sights, the Moon was centered — meaning the sights are co-axial. The ground needed to know this to confirm the feasibility of performing orientation and orbit correction of the Soyuz-T6 — Salyut-7 — Progress-15 complex using only the transport ship’s systems, since it still had plenty of fuel remaining, which of course they wanted to use.

We did everything except film the Sun. As it descended behind the atmosphere, I lost it while tracking with the film camera’s telephoto lens, whose field of view is nearly equal to the Sun’s angular diameter, and the dense filter of a thousand-fold reduction also hindered observation.

In the evening, we met with our families as we passed over the Far East. It was already dawning there. It seemed to me Lyusya was in a bad mood. Vitalik is doing great: he got six A’s and one B for the week. Back on Earth, he never delighted us with such results. Are they lying? Maybe it’s part of our psychological support. Lyusya told me that my friend Oleg Zebrov found my first teacher in Leningrad — Nadezhda Ivanovna — and on Teacher’s Day came to her home with flowers to congratulate her on my behalf. Today we said goodbye to our comm operator Volodya — his program has him starting airplane flights. The thing is, communications at Mission Control are handled by our guys from the cosmonaut corps. We fly, while someone else prepares — they still have everything ahead of them. Wished him all the best.