MARS stands for Machine learning, home Automation, Robotics and Space exploration.
Miller, an IT consultant who has worked for companies like Stanford School of Medicine, got wind of the event when he saw a Blue Origin rocket sticking up over the hotel's hedge. He immediately recognized what it was and who it belonged to.
But the event wasn't exactly a secret. People were tweeting out various pictures, mostly of the robots.
According to someone who works for the upscale Parker Hotel, in Palm Springs, the conference lasted three days and Amazon booked out the whole resort.
Amazon held MARS 2016 a year ago at the same locale, where 130 invitees from tech and Hollywood showed up. The event included a fireside chat with author Dan Brown and director Ron Howard.
Here's what we could see of this year's conference.