29 June 2007
On January 9, 2007, Steve Jobs announced iPhone at the Macworld convention, receiving substantial media attention. Jobs announced that the first iPhone would be released later that year. On June 29, 2007, the first iPhone was released.
What device, a tool for studying astronomical phenomena, uses the fact that when a material is heated to incandescence it emits light that is characteristic of the atomic makeup of the material?