China has recently disclosed some more developments in its space laboratory and space station program. We can expect China's next space laboratory, Tiangong 2, to launch in 2016. The large Chinese Space Station will be launched around 2022. The overall structure of these plans has not changed from previous announcements but the dates seem to be slipping. Should we be concerned?

Not really. China's space station program is still on track. The station was originally expected to be launched "around 2020", so the latest timeline is still fairly consistent. We had expected Tiangong 2 to be launched in 2015. A slip like this isn't really a big deal.

What has prompted these developments? It's probably just some mundane engineering issues. This analyst suspects that the root cause is not the space hardware to be launched but the rockets that will be used in these programs.

Tiangong 2 is expected to use the same sort of short, stubby module as Tiangong 1. This is a small pressurized cabin with a single docking port. However, the mission will be changed. Tiangong 2 will receive a visit from China's first cargo spaceship, Tianzhou, which is itself based on the design of the Tiangong module. Ironically, the cargo ship is larger than the space laboratory it will visit.

Tiangong 2 is expected to receive one crew expedition. This will probably consist of three astronauts launched aboard the Shenzhou 11 spacecraft. Tiangong 1 received two crews.

The Tiangong 2 module will be launched atop a Long March 2F/G rocket, which is a modified version of the Long March 2F. The 2F/G has only flown once before, and that was the launch of Tiangong 1. The Shenzhou 11 spacecraft will be launched atop the Long March 2F rocket, which has proven its worth with every launch of a Shenzhou spacecraft. It has never failed.

Now to the rest of the fleet. The Tianzhou cargo spacecraft is too large and heavy for any Long March 2F variant. It will use the Long March 7 rocket, which is still under development. The heavy modules for the Chinese space station will use the powerful Long March 5 rocket, also a work in progress. These new rockets are expected to fly from China's new launch site on Hainan Island, which is still under construction.

There's a lot of untested infrastructure in this mix. This analyst believes that China has hit some problems in the development cycle, and needs more time to fix them. Fair enough. This always happens when new rockets make their debut.

Overall, there's more good news than bad news in the latest batch of media releases from China. The human spaceflight program is still on track. It's moving slowly, but this is typical of the way China runs things. We just need to be patient. It will be worth the wait.

Dr Morris Jones is an Australian space analyst who has written for spacedaily.com since 1999. Email morrisjonesNOSPAMhotmail.com. Replace NOSPAM with @ to send email. Dr Jones will answer media inquiries.