With the abundance of images and sources available on the internet, it can be difficult to sort through them and select images that fall under fair use and are free from copyright laws. The last thing to worry about while writing a paper or preparing a presentation at three in the morning is the credibility and authenticity of the images utilized. This guide helps in finding images ranging from stock photos to stickers to icons to high resolution digital scans of paintings. Along with images, the guide also provides information about copyright laws and how to cite images.
Gunn, Chris. Optical Telescope Element Simulator. 2015, NASA, Goddard Space Flight Center, Greenbelt, Md. Accessed 29 Nov. 2016. https://www.nasa.gov/multimedia/imagegallery/image_feature_2237.html