Your exposure is a little long as the stars have tails - this happens because the earth has moved during the exposure.
Not sure which you are trying to capture here - is it the stars in the sky or the aircraft?
Firstly for any night time photo I would suggest using manual mode so you have full control over the exposure and the focus (i.e. manually focus as well).
If it is the stars - I would suggest opening your aperture up as wide as you can - not sure what the Sony RX100 max aperture is but something around F2.8 is good.
Then try a 25 second exposure to see if there is no tails on the stars - may even have to go lower but increase your ISO.
If it is the aircraft - I would suggest an aperture of F8, shutter speed of around 20 seconds (or longer), ISO around the 1600 mark and use a light source to paint the aircraft in.
Here is an image of mine where I have light painted the building in.
Canon 6D with the Samyang 14mm F2.8 lens shot at F2.8 @ 25 secs ISO 3200 and an external light source on the building.
Same image without the light painting with the same settings as above.
I hope this helps.
Karl
