In 1901 Nikola Tesla published an article in which he describes the possibility to communicate with other planets through radio waves. His hypothesis can be seen as part of a speculative field shaped by spectral theories based on a common ground where scientific and spiritual beliefs were indistinguishable. Are there messages hidden in chemical elements that we could trace though spectral lines? More than a hundred years later intriguing signals coming from the universe challenge skeptics and ask for attention. Are we being mesmerised, our brains directly affected by extraterrestrial electromagnetic radiation?