First view of Omega Centauri through my friend's 10", I was absolutely gobsmacked! I had no idea that such a view were possible through your average backyard observing night. From then I was hooked! It was also the first elusive object I found by myself in the sky besides Jupiter and Venus.
Partial Lunar Eclipse last December. Absolutely blew me away! I was so excited about seeing it, I travelled to the coast on a work night by myself just to view and photograph it.
Not Celestial per say but astronomy related. Getting up at 4:30am one Saturday morning to watch the very bright ISS pass overhead. I could barely contain myself from jumping up and down
I'm very new to astronomy so I haven't seen much else. But hope to in the future!