How general should my introduction be? I'm a high schooler (rising senior) writing a research paper on astronomy for the Siemens and Regeneron STS competitions coming up in the fall. My research advisor at my high school wants me to start my introduction very generally (basically almost wants me to write a review of modern astronomy) before diving specifically into my research, whereas every single other research paper I've seen (competition submission or one in my field) starts broad in the first sentence and gets specific immediately.

I'm not sure whose advice to follow. Besides their websites, I can't find much guidance or past successful papers for these competitions (only have found 2 total papers and an outdated ScienceBuddies blog post), so I'm reaching out to you guys. Should I start very general and slowly hone into my topic or should I focus on my specific the entire way through?
Thanks!
The introduction of a paper has many important tasks. It introduces the topic you will discuss, it gives an overview over the field, etc. One important point, that is sometimes forgotten when strictly following the formal rules, is that a good introduction should answer the readers question "Why should I care about this?". For this, you need to know your reader, you need to know who is your target audience. If you are writing for a broad audience, then it is good to first introduce the general setting, as proposed by your advisor. If, on the other hand, you are writing for a very specific audience of experts, they might get bored if you spend two pages telling them what they already know. Thus, step one should be to figure out who you are writing for. Once you have this figured out, ask yourself how you can motivate them to read your work, to be interested in your results. Do your results have some sort of impact on their life, on their work? If yes, this should be made clear in the introduction. 

In short, a good introduction covers all needed points (overview of the field, content of the paper, etc.) and furthermore motivates the reader to keep reading. Note that this motivation is also influenced by your writing style, your language skills, etc.



edit: Regarding the question who is right, your instructor or the other authors: I googled STS and found the term "Society for Science &amp; the Public", so it looks like it might be for a public audience. However, I'd advice you to look into it a little more before deciding, maybe also ask your advisor about it.