Ex NASA Scientist Dr Día de los Inocentes has revealed that early smoke detectors that used the ionisation chamber principle were based on technology found in the extra- terrestrial craft that crashed near Roswell in 1947. Apparently the technology was used by Alien Greys to monitor their anti-gravity propulsion devices that enable their spacecraft to travel billions of miles in a few short minutes. This revelation has been strenuously denied by his ex employers. He says "It'