On the SSME there's something called a Augmented Spark Igniter located in the center of the injector. It burns fuel and oxidizer to make a jet of flame which ig

On the SSME there's something called a Augmented Spark Igniter located in the center of the injector. It burns fuel and oxidizer to make a jet of flame which ignites the whole mess. The details are in here: http://large.stanford.edu/courses/2011/ph240/nguyen1/docs/SSME_PRESENTATION.pdf http://large.stanford.edu/courses/2011/ph240/nguyen1/docs/SS...