Dale, Moscow time (MST) is UTC+3h. So, if pass time is 0430 Moscow time this equal to 0130 UTC. MST (or so called Moscow Decree Time) is standard time scale used Russian spacecraft controllers. As for term "day orbit", it is used by controllers of Mir as some convenient one. Each day ground trace of one of current orbits is passing close to the some "fictitious" ground trace which we are using as "reference". Orbit with such ground trace we are calling "1st day orbit". Ascending node of the 1st day orbit is the first one which is situated westwards of 17E and it's longitude is most close to 17E. Making few day propagation for Mir orbit you will see that there are two typical days - with 15 or with 16 day orbits. Such count is very useful for us during flight planning, including launch of Progress and Soyuz which is always take place on the 1st day orbit, standard docking strategy which foresees close approach and docking oh the 2nd day orbit etc. Depending of 15 or 16-orbit day we have all visibility zones for ground stations are on 12th-15th,1th-5th or 13th-16th,1th-5th day orbits. Best regards, Vladimir Agapov.