What do these figures refer to?
- his theoretical paper "Free Space" was finished
- he suggested the 16-step plan for the human space exploration
- the age when he got ill which resulted in his partial deafness
- he got the teacher’s certificate
- his paper "Free Space" was published
- he went to Moscow at that age
- the year of his death
- the year when the work which discusses the idea of rocket space exploration was published
- the number of children in his parents’ family
- Jules Verne’s book "From the Earth to the Moon" was published
- the age at which he died
- his science fiction novel about asteroid mining and orbital stations was published
Look at the list of theories and ideas. Tick those that were put forward by Tsiolkovsky. Look back in the text if necessary.