In terms of aerospace-related facilities on Tanegashima, the Space Center in Minamitane Town quickly springs to mind, though Nakatane Town has the Masuda Tracking and Communications Station.
This facility is mostly used for tracking and controlling artificial satellites and the premises are dotted with parabolic antennae.
I wasn't able to get very close, but I did get a sense of them from a distance.
The facility also has public displays for civilian visitors.
If you're interested in space, the exhibit room, with models of satellites, explanations of the observation facility, more details on satellites, and an outline of a day in the life of an astronaut, will feed your curiosity. Probably the most exciting booth is the one that lets you make a postcard of yourself wearing a space suit.
What I loved best was, if you fill out a survey, you can get trading cards with pictures of antennae.
These cards are only available at JAXA facilities around Japan and there are different ones at each location.
I was overjoyed to be able to get a souvenir not sold in stores.
The Space Center is full of energy and activity, but the Masuda Tracking and Communications Station is less known and enveloped in tranquility.
Nevertheless, like the Space Center, it still makes you feel like a kid again.
If you want to get up close and personal with space, I think this is one good destination.