Hi Steve,
I run into a lot of challenges at work, particularly when I start a new project. When I start working on a project in an area that I have never studied before, I need to do a lot of reading to find out the current state of knowledge in that area. New scientific papers are published almost every day, so developing a solid background in past research, while keeping up with the new research as it is published can be very difficult. When I start new projects I may also need to learn new computer programming skills and analysis methods, or use electronics skills that I haven't used since college. Fortunately, I have access to a large library and the Internet, so I can read books and articles to help me learn the skills that I need. I also know lots of other scientists who I can ask for help.
The thing I find most disappointing about being a scientist is how much politics affects my ability to do research. My work is primarily funded through research grants from government agencies like NASA and the National Science Foundation. When I have an idea for a new research project, I need to submit a proposal to programs sponsored by these agencies. Unfortunately, the budgets of these agencies and which programs they sponsor are strongly influenced by the policies made by Congress and the President. It can be very frustrating to have an idea for an interesting project, but not have any money to do it because the project's topic is not currently a high priority for NASA or the National Science Foundation. Getting research funds can be difficult, so many scientists work on 2-3 different projects at the same time and are constantly looking for new projects. This way, if money to support one research project runs out, we have other projects in areas that are well-funded.
Kris