Real photos of solar systems.
I think I put the idea together myself before reading it from scientists. If a star is the heaviest object around, and massive amounts of rocks or dust are circling so fast they won't be sucked in, then gravity might coax that much debris to conglomerate and congeal. Not into one big mass, but in patches, with some variation depending on the speed and distance of whatever formed. That explains how a chaotic mess with only a star, given vast time, could become a solar system. Discovering this was accepted science was a thrilling affirmation, but had I even considered I'd see a real photograph of this process? I don't think I even dreamed it.
The image here seemed too extraordinary that I assumed the actual it the artist's rendition, and after a double take, I hunted further for the disclaiming caption. Look at that thing. It's real.
That's one of two photos taken with the Very Large Telescope's "SPHERE" instrument, specialized to illuminate a system by selectively blocking the light of its star.
The second, with a subject also hundreds of light-years away, is also breathtaking: an actual image of a system with two visible planets. (Plenty of extrasolar planets have been cleverly detected, but actually photographing them is rare; I think this is the first image ever of two in one system, differentiated from the background stars by their movement.)
These are significantly larger and farther out than Jupiter. What does that imply? More dust that was swirling thinner and faster, to maintain that distance and collect over time into such gas giants?
That's only my first speculation as an amateur, but even the basic premises on which to base such speculations wouldn't have been available some decades or centuries back, and only this era are these "real-world" examples shedding light on the range of possibilities.