Thats no Moon, Thats a space station!
If you need new pads anyway now is the time to swap them over as its not hard and you can check the sensor setup then.
My car did this recently and it was beacause the connector to the brake pad wasnt clipped on so wasnt making a full connection.
Audi S3 8L BAM 225 2002 - Ming Blue : Silver Heated Leather, Armrest, RNS-E - Bose, Alloy Mirrors, 18" RSTT`s, Sunroof, Cruise, AutoDim Mirror & Usual S3 Extras.
Mods : Badger 5 Stg 2 Custom Map, FMIC, 3" DP & 200 Cell Cat, 007P, Jetex Filter & 80mm TIP & Heatshield, Complete LED Kit, Gen VW Aero Wipers, Full Powerflex Kit, R32 RARB, AP Shocks & Springs, 15mm Front & 20mm Rear Spacers, BB Uprated Actuator, N249 Delete & Catch Can, AP TVR 4Pot Brakes & DS2500`s, Sachs Carbon/Kevlar Clutch