Learn English – word or short phrase used to describe being impressed with someone’s accomplishment while also clearly expressing a lack of understanding

(This is my first time on this forum, so I apologize in advance if I fail to articulate my query effectively or break site etiquette out of ignorance. I'll endeavor to be as thorough as possible here because I feel as though my question might be quite obscure, so this post will likely be very long.)

I am in a situation where I feel the need to congratulate someone for something they recently achieved and were formally acknowledged for by others. However, the accomplishment lies in a field I am grossly unfamiliar with, and so I am unable to make any specific compliment due to my lack of knowledge and experience in that area. This also extends to the award itself in that I am unsure just how significant it is overall (my intuition and a quick internet search suggest that it is a fairly big deal).

What I am after is the most concise way (preferably a single word or short phrase) that I can express through writing as sincerely as possible that I am impressed by their achievement (and it's obvious acknowledgement by others relevant in the field), while also letting them know that, while my compliment is genuine, it holds no basis in my own understanding and that I find myself equally amazed and confused to the point where I recognize a job well done, but can't really say much else.

I was unable to find any other relevant information – it looks like I might be the first person to ask about something like this.
I do recognize that saying something to the effect of 'That's impressive, congratulations!' then just briefly explaining my ignorance might be sufficient, but I would very much like to know if there is a better way to approach this.

(Thank you for reading, I hope that was clear enough and made sense.)

EDIT: I suppose that it doesn't help that I wasn't specific enough as to the exact intended usage.
The individual I mention is a musician, and not involved in a scientific discipline as some of you have speculated. I have asked for a way to congratulate him in a way that intentionally exaggerates my position as an outsider to add a comedic overtone to an otherwise sincere compliment. The difficulty is that I have to do so in writing, and I was just after some ideas.