What is DAHAP?

I have often felt a need for a collection of images from the history of astronomy, for use in research and teaching. DAHAP is a resource that aims at filling this need.

Most of the pictures in the collection were scanned from old works. Note, however, that I make no guarantee that these pictures are in the public domain; I advise you to check the copyright status of a picture before using it. Use them at your own risk. Some of the pictures have been determined to be copyrighted; you will have to settle the details with the copyright owner before using such a picture. These pictures are noted as being copyrighted in the documentation of the archive.

If you publish a picture (in print, a computer application or any other media), state the source, and send a copy of the publication to me. If you publish the picture on a webpage, you should put a link to the DAHAP page (http://www.kunskapsbolaget.com/DAHAP/) by the picture.

Whatever use you put the archive to, I would like to hear from you!


DAHAP evolves in a stochastic manner. Therefore, you might very well find many important astronomers, instruments etc. missing, while there are several lesser figures included. Of course, the selection is also a reflection of my own interests and what materials I have at hand. Hopefully, this skewness will become less apparent as the archive increases in size.

The level of documentation is varying. The minimum of information provided is the source of the picture, and a short note identifying the content of the picture. Sometimes more information might be supplied.

The pictures are provided in two formats. Grayscale pictures are saved in jpg-format, whereas drawings and engravings are saved in gif- format, as it seems that jpg-files must be in 256 colours. Saving the linedrawings as gifs allows them to be saved in 2 or 16 colours. This mix of two formats is somewhat annoying, but it reduces space in the archive.