How to get the index files required to run the Astrometry.net code
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2007 September                                 Astrometry.net team

1. Preamble

One of the goals of the Astrometry.net project is to "organize,
annotate and make searchable all the world's astronomical
information."

We have put a lot of effort into building our solver, and we want to
distribute the source code and the data files that make it tick.  Our
project is all about making data accessible, and if we want to become
a central part of astronomical data processing and storage, then our
system must be transparent.  Also, by releasing our source code we
hope to unleash the creative power of our users, who will adapt and
extend it to their own purposes, doing things we haven't even thought
about.

We want our code to be open.  However, we want to avoid a situation in
which people use our code in ways that don't lead to data becoming
more accessible.  We're trying to encourage universal data
availability by attaching some conditions to our data files.

Our code is distributed under the GPL, and we won't impose additional
conditions on its use or distribution.  However, we are also
distributing data files that are required to run the solver, so we are
applying conditions on the distribution of these files.

2. Conditions

Astrometry.net are making available a set of data files ("indexes") under
the following conditions:

 * NOT-FOR-COMMERCIAL-USE: Because the indexes represent a re-release of
   data originating in the USNO-B Catalog, the indexes may not
   be used for any commercial purpose whatsoever without prior written
   consent from our team.  Our consent will only be granted to
   commercial users for use in public, not-for-profit projects they
   are engaged in or supporting.

 * CREDIT: If the indexes are used in a system which provides a public
   web service, then any web page that makes use of the results must
   clearly display the following text:
   "This service uses tools provided by Astrometry.net.
    For more details visit http://astrometry.net/ ."

 * PUBLIC SERVICES MUST BE OPEN: If the indexes are used in a system
   which provides a public web service, then any astronomical images
   solved using the indexes (alone or in conjunction with other data)
   must be made available to any other interested party including the
   Astrometry.net team.  The image files may be made accessible by
   providing a list of URLs, by granting network access to a source
   control repository or database, or by giving access to or sending
   physical media.

 * ACADEMIC CITATION: If the indexes are used in any scholarly work,
   research grant proposals or other scientific or academic
   publications, the Astrometry.net project must be properly cited and
   acknowledged.  The paper to cite is the Lang et al paper on our
   bibliography page http://astrometry.net/biblio.html .  The
   acknowledgement text is "This research made use of tools provided
   by Astrometry.net."

 * NO REDISTRIBUTION: Redistribution, copying, posting, mirroring, or
   hosting copies of the indexes or information sufficient to obtain
   the indexes is not permitted.  In other words, the only legitimate
   way for someone to have the indexes is for them to have obtained
   them from us directly.

3. Obtaining the indexes

Send an email to the user "code" at the domain "astrometry.net"
stating clearly your intended use of the indexes, and stating
explicitly that you have read and agreed to the conditions in this
text file.  We will return to you information required to obtain the
indexes.  That information may not be redistributed, as noted in the
conditions above.
