First release of Footprint Services

[Tamas Budavari]

Hi Everyone,

We are happy to announce the first release of Footprint Services for the
Virtual Observatory. In case you missed the ADASS in Tucson last week,
below please find the abstract of the talk that introduced the new portal
at
	http://www.voservices.net/footprint/

I am delighted to see that our recently published online repository is
being used as intended and people have already started submitting the sky
coverages of various surveys. Thank you! The list now includes SDSS, 
GALEX, UKIDSS, CFHTLS and more. Enjoy!

We'll keep improving the site, the web services and the content over time
and we hope you all will find it useful. Feedbacks, as usual, are welcome!

Cheers, T.
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(O4a.1) Footprint Services for Everyone
	Tamas Budavari (The Johns Hopkins University)
	Laszlo Dobos (Eotvos Lorand University)
	Alex Szalay (The Johns Hopkins University)
	Gretchen Greene (Space Telescope Science Institute)
	Jim Gray (Microsoft Research)
	Arnold Rots (Smithsonian Center for Astrophysics )

There is much more to astronomical observations than just source catalogs. 
For example, when working with multiple observations at different 
wavelengths, knowing their precise coverages is just as important, e.g. to 
look for dropouts, and can be very difficult in case of the most 
significant observations that are often the most complex, as well. This 
functionality has been missing almost entirely from the toolbox of many 
astronomers until today.

We present high-level user and Web services for dealing with astronomical 
survey geometry of arbitrary complexity. Based on our high-performance 
spherical library, we built an online public repository of footprints 
preloaded with the coverage of some of the most widely used datasets today 
including the Sloan Digital Sky Survey (SDSS), the Galaxy Evolution 
Explorer (GALEX) and the Hubble Space Telescope (HST) exposures. We 
publish a Web based toolkit that enables advanced spatial searches for 
regions of interest on the sky, Boolean operations on selected footprints 
(union, intersection), on-the-fly visualization, and exact area 
computation. We also provide an easy-to-use interactive footprint editor, 
as well as a simple upload facility. The results of the searches and 
region manipulations can be saved and published on the footprint server or 
downloaded in various formats including ASCII and the VO compliant 
Space-Time Coordinate (STC) region representation.
___

Tamas Budavari

Dept. of Physics and Astronomy       
The Johns Hopkins University         
3400 N. Charles Street 
Baltimore, MD 21218                    
Phone: +1 (410) 516-0643
Fax: +1 (410) 516-5096
http://www.sdss.jhu.edu/~budavari