The second half of 2016 has been rough for International Space Station mission planning. All of the visiting vehicles that service the outpost have had some delay or another.
First, in early August the Japan Aerospace Exploration Agency announced their Kounotori 6 spacecraft would be postponed from its Sept. 30, 2016 launch date due to a "slight leak" found in the pluming of the cargo ship. After fixing the problem, the Japanese space agency is now targeting Dec. 9.
Kounotori 6 will be launching to the ISS six new lithium ion batteries to replace the existing nickel-hydrogen batteries. At least two spacewalks will be required for astronauts to install them.
These extravehicular activities were originally expected to take place in October during Expedition 49. Now that the Japanese cargo ship has been delayed, they are now expected sometime in December or January during Expedition 50.
On Sept. 1, a SpaceX Falcon 9 rocket exploded on the launch pad during a fueling test. This prompted the NewSpace company to postpone all future Falcon 9 launches until they cause of the explosion is identified.
In a recent statement, SpaceX said it is nearing the conclusion of their investigation and hopes to resume launches in mid-December.
Not long after the Sept. 1 explosion, it was discovered the Soyuz MS-02 spacecraft had short circuit requiring replacement. This delayed that launch by nearly a month. The crew finally launched Oct. 19, docking with the ISS a couple days later.
Delaying the Soyuz MS-02 had a cascading effect that has since delayed the Progress MS-04 cargo ship from mid-October to Dec. 1, 2016. Additionally, the launch of Soyuz MS-03 carrying NASA astronaut Peggy Whitson, Russian cosmonaut Oleg Novitskiy and European Space Agency astronaut Thomas Pesquet has been bumped by a couple days to Nov. 17.
Throughout all of this were the ongoing delays of Orbital ATK's Antares rocket carrying the company's OA-5 Cygnus. The upgraded rocket was originally targeting June 2016 for flight. However, more testing ultimately delayed the launch to July, August, September, and finally, Oct 18.
After launching, Cygnus spent a week in free-flight before being captured and berthed Oct. 23 to the Unity module of the ISS. It is expected to remain there until late-November.