This lists the logos of programs or partners of NG Education which have provided or contributed the content on this page.
Content Created by
-
The idea of concentrated solar power is 100 years old. Explore the journey from Philadelphia a century ago to the Sahara of the future.
Classroom educators and outreach professionals can register to download HD segments for free by visiting the Educators section of the Earth: The Operators' Manual website.
Media Credits
The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
Courtesy
Last Updated
Nov. 19, 2013
For information on user permissions, please read our Terms of Service. If you have questions about licensing content on this page, please contact ngimagecollection@natgeo.com for more information and to obtain a license. If you have questions about how to cite anything on our website in your project or classroom presentation, please visit our FAQ page.
Media
Some media assets (videos, photos, audio recordings and PDFs) can be downloaded and used outside the National Geographic website according to the Terms of Service. If a media asset is downloadable, a download button appears in the lower right hand corner (
) of the media viewer. If no button appears, you cannot download or save the media.
Text
Text on this page is printable and can be used according to our Terms of Service.
Interactives
Any interactives on this page can only be played while you are visiting our website. You cannot download interactives.
Funder
This material is based in part upon work supported by the National Science Foundation under Grant No. 0917564. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation.