Title update, sources and source evaluation

After doing some preliminary research I have decided that evaluating different spacecraft propulsion systems wouldn't be a suitable study as there are simply too many types to evaluate. Furthermore, I could not find a suitable reason to only evaluate a select few either.

For my new topic I have decided to instead to research the effects of cosmic rays on the health of astronauts on a long distance space expedition, for example a mission to Mars.

There is suitable information available on the topic since NASA and other space agencies are currently deep in research about getting humans to Mars, and the issue of radiation protection is important.

I will divide my topic into several sections:

What are cosmic rays?:

 - describe different types

 - what are they and where do they come from

How do cosmic rays affect humans?:

 - List, describe and explain health effect

 - Cite various studies

How will the astronauts be protected?:

 - List current and developing methods

 - Evaluate and compare

Conclude and assess if a long distance mission is worth it considering the health risks coupled with available protection.

I have also done about two hours of source research for each of the sections and I am currently compiling a list of potential sources for my essay and I am assessing each source to make sure it is reliable and trustworthy.