Following the rollout of the rocket for China's Shenzhou 10 space launch on June 3 (China time), many facts have been officially disclosed about the upcoming mission. The flight of Shenzhou 10 will last more than two weeks and will be China's longest astronaut mission to date.

We have a fairly good idea of what to expect for Shenzhou 10, but some major parts of the puzzle still remain to be disclosed. China has a habit of keeping information about its space launches under wraps, and sometimes does not disclose facts until the last hours before launch, if at all.

At the time of writing, we have had no official word on the date or the exact time of launch for Shenzhou 10. For technical reasons, Shenzhou 10 can only launch during fairly brief "launch windows" which appear roughly every two days. This is caused by the plan to dock with the Tiangong 1 space laboratory, which has been in orbit since late 2011.

Tiangong must be in the right position with respect to Shenzhou's launch site in order to make a rendezvous and docking practical. It is generally expected that Shenzhou 10 will launch in the evening of June 11 (China time), but this is still not confirmed, and it is still not the only option available to China.

In turn, our uncertainty over the launch date also affects our knowledge of the timetable for the rest of the mission, including the docking with Tiangong and the return to Earth. Once the launch date is known, it will be straightforward to roughly estimate the time of some of these events, but for the moment, we can't be precise about anything.

Another prominent "missing part" is the official identity of the crew. China has made no secret of the fact that Wang Yaping, a female astronaut, will be aboard the spacecraft. This was publically disclosed long before China usually nominates its crews in a typical pre-launch timetable.

However, the identity of the two astronauts who would accompany her on the mission was not disclosed when Wang was named, and their identities still remain officially unconfirmed. Analysts have speculated on their identities, based on crew rotation patterns, but we could still be potentially surprised when the names are announced.

We know that the Shenzhou 10 spacecraft will spend around 12 days docked to the Tiangong 1 space laboratory. However, we know very little about the tasks the crew will perform aboard the laboratory. It has been disclosed that the astronauts will conduct a televised lesson program for school students, which will probably involve showing what it's like to live on board the laboratory and how strange things happen in weightlessness.

We also know that some experimental samples will be taken back to Earth when the expedition to the laboratory is complete. We can speculate that some of these samples will include tissue and body fluid samples from the astronauts themselves. Beyond this, we don't know very much.

This analyst has previously noted that media coverage of Shenzhou 10 seemed to be very cagey. Space analysts are used to working with slim leads from the Chinese media, but this time, there has been even less information than usual on some fronts. Too many pieces are still missing from the puzzle.

Dr Morris Jones is an Australian space analyst who has covered the Shenzhou program since 1999 for Spacedaily.Com. Email morrisjonesNOSPAMhotmail.com. Replace NOSPAM with @ to send email. Dr Jones will answer media inquiries.