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 ("index
files") under the following conditions:

 * NOT-FOR-COMMERCIAL-USE: Because the index files represent a
   re-release of data originating in the USNO-B Catalog, the index
   files 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 index files are used in a system that 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 index files are used in a
   system that provides a public web service, then any astronomical
   images solved using the index files (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 index files 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 index files or information sufficient to
   obtain the index files is not permitted.  In other words, the only
   legitimate way for someone to have the index files is for them to
   have obtained them from us directly.

3. Obtaining the index files

Send an email to the user "code2" at the domain "astrometry.net"
stating clearly your intended use of the index files, 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
index files.  That information may not be redistributed, as noted in
the conditions above.  If you don't get a reply to your email within
24 hours, please send us a reminder.
