As much as many people dream of being an astronaut when they are young, being an astronomer is no guarantee someone will also want to become an astronaut.

I personally know of a handful of astronomers that aspire to be an astronaut, but for the most part, many of us are content to study space from afar, grounded on Earth.

To become a professional astronomer or astrophysicist, many people complete an undergraduate degree (often in maths, physics, astrophysics, engineering or computer science, though not always, it can depend on the research field. One of my majors was geoscience) and one or more postgraduate degrees (like a masters or PhD) and then get a job at a university, a telescope, or some other type of research institution.

To become an astronaut is a very different process.

In many cases you have to be a citizen of the country whose space program you are applying to join. Australia currently doesn't have a crewed space program, although these rules may change as commercial space endeavours become more popular.

Although the undergraduate degrees fields of interest are similar to those for an astronomer there are a few others: engineering, maths, physics, chemistry, biology, geoscience, computer science, medicine and then relevant experience is also required. The crews need to have a range of people with a range of skills to make sure they are properly prepared and will have a safe and successful mission.

Since a lot of the work astronauts currently do is on the International Space Station (ISS), it's also important they can communicate with their colleagues, and so many have to learn an additional language, such as Russian. This is especially important, since missions on the ISS can last close to a year!

There are multiple roles for astronauts: mission specialists have a variety of science, technical and medical skills; pilots need to have some of the same technical background and over 1000 hours of experience piloting a jet aircraft - as such many pilots traditionally had military (air force and navy) backgrounds.

There's also a lot of training in zero-gravity, training as an analogue astronaut (training on Earth but with all the gear you'd need in space), plenty of training underwater (astronauts often get scuba licences while training), as well as training for how to handle the different scenarios you might encounter once in space.

So even though an astronomer could be academically qualified to be a mission specialist astronaut, there are further qualifications you have to get to become an astronaut, and it is highly competitive, with only 20 or so spots opening every few years, and with 1000s or applicants each time.

So if you don't think being an astronaut would be right or you, remember you can always enjoy space and astronomy from right here on Earth, and you don't even have to be a professional to enjoy it, just take some time to wonder at the night sky and you're already well on your way!