Visually impaired students often find the study of astronomy difficult because so much of the content is presented visually. One method of providing access to astronomy information is to create raised line drawings or other tactile graphics of images such as star charts and planetary maps. Another is to create three-dimensional models to represent objects such as planet spheres.
Online resources, including those described below, are available to help instructors and support staff make the study of astronomy more accessible to students with visual impairments.
The Space Exploration Experience (SEE) Project for the Blind and Visually Impaired  website provides space image downloads that can be easily made into tactile graphics and integrated into instructional activities in astronomy courses. SEE Project staff developed and tested these tactile hands-on materials.
Adapted Curriculum Enhancement  (ACE), a joint program of NASA and the Mid-continent Research for Education and Learning, has developed learning modules specifically for students who are blind. Educators can download instructions and materials to support classroom lessons.
An extensive listing of resources for teaching astronomy to students who are blind is included in the article Resources for Making Astronomy More Accessible for Blind and Visually Impaired Students  by Noreen Grice.
The Tactile Graphics Assistant  (TGA) is a program created at the University of Washington to aid in the tactile image translation process. The TGA separates text from an image so that the text can later be replaced by Braille and inserted back onto the image. You can view an example of a final product of accessible images for people who are visually impaired in the text An Introduction to Modern Astrophysics .
Accessible versions of astronomy text-based materials may also be available from Bookshare.org .
-  Space Exploration Experience (SEE) Project for the Blind and Visually Impaired
-  Adapted Curriculum Enhancement
-  Resources for Making Astronomy More Accessible for Blind and Visually Impaired Students
-  Tactile Graphics Assistant
-  An Introduction to Modern Astrophysics
-  Bookshare.org