At the Green Bank Telescope the radio telescopes are so sensitive to radio waves that any possibility of radio frequencies interface is readily taken into account. Spark plugs are a source of man-made radio waves which interfere with the radio telescopes at the National Radio Astronomy Observatory. Most vehicles with spark plugs are not permitted to drive near the telescope, so diesel cars have to be used like the Checker Marathon seen above. Telescope Radio Sparkplug Oldschool Blackandwhite Green Marathon Checker National Observatory Waves Allnight Uvatrip Parked Interfaces Frequency Science Nightsky Follow Stars Galaxy Car Vintage Transport Instadaily instafollow instagood picoftheday ztprod