World Space Week is a kind of holiday that is held from the 4-th up to the 10-th of October. This type of celebration was established by the United Nations General Assembly. This international celebration of science and technology is well-known to scientists and those who are interested in scientific research. It is not a professional holiday or whatever, but almost all students and teachers of science, for instance, physics, knows this famous World Space Week and it is broadcast on the news, for example, some discoveries during this week.
The World Space Week`s beginning and end recognize the launch of the first human-made Earth satellite, Sputnik 1,on the 4-th of October in 1957, and the Outer Space Treaty which was signed on the 10-th of October in 1967. Anyway, if you try to Search some information about this event on the Internet, I am pretty sure that you will find it on different websites. Except for the information presented on the Internet, you might find pictures and photos of space, spacecrafts, and lunar rover, for example.
So, I suppose that the topics of such kind are also important to discuss with students in English, certainly if they are major in science because it will be easier for them to understand the message of the presentations and they will get interested in answering the questions concerning space.