I have a Konica too, a slightly different model SLR, and a Konica rangefinder. Nice cameras. I don't know what lens/lenses you have.
For just about any subject you should get some nice pictures with the Konica, but yeah, astrophotography seems to be rather specialized. Try searching on here, I think J Secord is one that does that, does long exposures, night sky, etc.
It might be a bit of a jump if you aren't familiar with film cameras to go from learning to load film etc. to doing astrophotography. But try
Film Photography Project | An Internet Radio Show & On-Line Resource for Film Shooters Worldwide - they have fun videos on topics like how to load film and other basics. They sell film too, sometimes have specials, etc. Or I buy film from
Adorama,
B&H,
Home | Freestyle Photographic Supplies , but for this weekend you'd probably need to go with what you can get where you live.
Before the weekend maybe practice some without film in the camera, and then practice loading and shooting a roll before you go. You wouldn't have time to get it developed but that would I think give you a feel for it. Those of use who learned on film had to learn how to see what's in the viewfinder and frame shots and think about what it would look like, if it will make a good picture.
Getting a proper exposure would be what you'd need to learn too. My starting point is f8 and 1/125 or 1/60, depending on the sync speed of the camera (usually in red on the dial); that's where I usually reset the camera when I'm done. For me f8 is a nice midrange aperture, and I can quickly open or close the lens a couple of stops either way. I don't usually go below the sync speed because for me, slower than 1/60 means finding a way to set up the camera somewhere stable or get myself braced to avoid shutter blur.
I usually use 400 speed (ISO/ASA) film indoors, lower light (evenings), 100 or 125 daytime outdoors.
Use the meter to tell you if you're getting enough light coming into the camera. If the needle bounces up and shows there's way too much light, you need to go to a faster shutter speed or shut the lens down a stop. (Still too much? adjust again.) If the needle doesn't move much or is showing not enough light, open the lens more or go to a slower shutter speed. I'd start out probably adjusting one setting at a time, then meter again, and go from there.
I'm just sharing suggestions etc. in case you want to do some general daytime pictures while you're there. Do you by chance have a shutter release that camera with the camera? something like this?
Midwest Photo Exchange PROMASTER 20'' Manual Cable Release I'm thinking I'd probably try to figure out a place to set the camera so it would be stable and use a release to minimize movement and guesstimate a few seconds' exposure and do a few shots, maybe varying the exposure time for each. But then I like to experiment.