The Chandra Astrophysics Institute (CAI) is an opportunity for students in grades 9-11 from a wide range of academic backgrounds to train for and undertake astronomy projects. The students are mentored by MIT scientists and use observations from the Chandra X-Ray space telescope.
On October 5, 1644 (or according to the old julian calendar September 25), Danish astronomer Ole Christensen Rømer was born. He is best known for making the first quantitative measurements of the speed of light.
On October 2, 1608, German-Dutch lensmaker Hans Lippershey applied to the States-General of the Netherlands on October 2, 1608, for a patent for his instrument "for seeing things far away as if they were nearby".