Introduction
The TAUVEX mission is a collaborative project between the Indian Institute of Astrophysics (Prof. Jayant Murthy) and Tel Aviv University (Dr. Noah Brosch) to fly a set of three UV imagers aboard the GSAT-4 spacecraft. A MOU was signed between Madhavan Nair (ISRO Chairman) and Aby Har-Even (then Director-General of the Israeli Space Agency) to this effect on December 25, 2003 and many subsequent meetings have taken place between ISAC and ElOp - the Prime Contractor for TAUVEX.

Most interface issues have now been settled and the instrument will be delivered to ISAC around March, 2006 in preparation for a late 2006 launch aboard the GSAT-4 satellite.

This report is a summary of the current status of the TAUVEX activities at the Indian Institute of Astrophysics. Our activities focus on the maximization of the science from the mission and therefore subsume many other tasks including software development and mission planning.

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Science
The TAUVEX instrument will perform an imaging survey of much of the ultraviolet (UV) sky to a depth greater than any previous mission. Despite its importance to many areas of astronomy (see Barstow 2004, Astronomy & Geophysics 45, 5.), the UV sky has remained largely unexplored because of a number of technical issues. The only survey of the entire sky was made in the early 1970s using the TD-1 instrument aboard the ANS satellite in three bands from 1400 - 3200 Å. Although the sensitivity (11th magnitude) and spatial resolution (1') are both low by modern standards, TD-1 data are still the primary source of data for any large scale work in the UV (see, for example, Sujatha et al. 2004, BASI, 32, 151).

Fig. 1: The UV sky as observed by the TD-1 all-sky survey. The sensitivity of the instrument is only about 11th magnitude. Our sensitivity will be higher by more than a factor of 1000.

More recently (2003), the Galaxy Evolution Explorer (GALEX) was launched by NASA to investigate the evolution of galaxies at low redshifts. GALEX is comprised of one telescope with a dichroic to split the light onto two different detectors, one in the FUV (1300 - 1800 Å) and the other in the NUV (1800 - 3000 Å). Although the original intent was to survey the entire sky, GALEX will now not do so, primarily because of lifetime constraints.

Unusually, but not uniquely, for a science mission, TAUVEX will scan along lines of celestial latitude. This results in a more complex science plan which must account for both the importance of the science and the feasibility given the pointing constraints.

The high-level science planning is led by Prof. N. K. Rao. The general considerations in this science planning is that:

1. The observations further our understanding of front-line problems of astronomy and astrophysics.
2. The scientific goals are feasible given our observational and instrumental constraints.
3. The data are unique; i.e., they have not been better addressed by other satellite data, such as that from GALEX.
4. The problems are of interest to the Indian scientific community.

To this end, we have identified a number of key areas with interested astronomers who will take the lead in defining the science problem and how best TAUVEX can address that problem. A meeting of interested astronomers from different institutions was held at IIA in July 2005 and the conclusions are summarized in the Science Plan Document.

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Software
One of the main responsibilities of our team at the Indian Institute of Astrophysics is to develop the software for the TAUVEX mission. We note that the data for the UVIT instrument is essentially identical to the TAUVEX data, with the exception of the input format, and, therefore, all programs written here will be used without modification for the UVIT data pipeline.

There are several aspects to the software development which must all be addressed to maximize the science return from the mission:

1. Development of simulations to model the instrumental data. These simulations will be used both to test the pipeline and for the mission planning.
2. Development of the pipeline software to transform the data from the instrumental data sent through the spacecraft telemetry system into science data products usable by scientists.
3. Development of an archival system to allow external scientists or, in fact, any interested party to download the data and the software. We have adopted the principle that, unless the data have been obtained as part of a user proposal, the Indian share of the data belongs to the Indian public and therefore should be accessible to everyone.
4. Development of an analysis system to allow scientists and others to extract useful scientific information from the data. Although we cannot meet the needs of every individual, we will, on a best effort basis, support the creation of general purpose tools to ease the examination of the data.

We have completed the first two items in the list above: the simulation of the data and the processing into usable science products. Of course, as part of our verification process, we have found many errors of differing severity and are now rectifying these problems.

Considerable effort has been spent in ensuring that all TAUVEX software is readily available and usable. All modules are well-documented and are available through the TAUVEX website. We are also developing web interfaces for each program so that they can be run with no programming expertise yet without sacrificing flexibility. One such module is shown in Fig. 2, a screen shot of the TAUVEX Exposure Time Calculator (ETC). Simply by entering the spectral type and magnitude of any star, the user can make an estimate of whether his or her object will be observable with TAUVEX. Other tools include both mission tools such as the Sky Simulator and more general science tools such as a model of the interstellar radiation field at any point in space.

Fig. 2: The TAUVEX Exposure Time Calculator (ETC) is one of the online tools available for users and potential users of TAUVEX data.

All TAUVEX modules are available under the GPL and have been posted on the TAUVEX website. While we have made every effort to ensure that all routines are well-tested, we realize that the real validation can only come from the user community. We have put a professional system for program development using CVS and Bugzilla through which we plan to be responsive and responsible to the user community.

The primary interface to the TAUVEX mission is through the project website (http://tauvex.iiap.res.in) and we have made a special effort to ensure that our website is accessible and attractive to both professional astronomers and to the public. It already contains a considerable amount of documentation about the design and implementation of the software pipeline and we are adding mission tools as they are being developed.

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Outreach Programs
While TAUVEX is a serious scientific instrument which will provide unique data and insights into many scientific problems, we must not forget that the prognosis for astronomy is quite poor in the country. As a discipline, we have underperformed and have significant problems in recruiting and retaining active researchers. We have also lost sight of the fact that most of the people in academics, both students and faculty, are in universities where the environment is not conducive to research.

We have made a special effort to reach out to the general community, particularly the student community from whence the next generation of astronomers will come. J. Murthy has given talks at many different institutions in Bangalore and outside in which TAUVEX has been emphasized (Appendix). This has resulted in two press interviews - in the Deccan Herald and the Hindu.

Also as a result of these talks, there have been more than 20 students from colleges both inside and outside Bangalore who have worked on parts of the TAUVEX mission. While most of them have gone to careers in industry, they have nevertheless become brand ambassadors for TAUVEX and, more broadly, for the Indian Institute of Astrophysics and even astronomy in general.

A noteworthy event was the exhibition on Observatories of the World at the Visveswariah Industrial and Technological Museum (VITM). With the help of the museum staff, we produced a TAUVEX poster which was displayed for several months at the museum and is now traveling around the country. We have also produced two further posters, which we plan to print and distribute.

We have held two workshops for scientists from around the country. These have garnered considerable interest and a number of people have submitted prospective observation programs. The first RESPOND proposal has just been accepted with Ranjan Gupta (IUCAA) as P.I. This proposal will use a neural network to classify TAUVEX sources. Prof. Gupta is now hiring a JRF who will, hopefully, continue on to a PhD with TAUVEX data.

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Personnel
The TAUVEX project probably consists of the largest group of UV astronomers in the country. The science lead is Jayant Murthy with Sujatha N. V. and Rekhesh Mohan as Post Doctoral Fellows. We will shortly make offers to three more Post Doctoral Fellows who will work in different aspects of the mission such as Mission Planning and User Support.

P. Shalima has just finished her PhD thesis and will remain at IIA for another year working on TAUVEX related scientific problems and Abhay Karnataki has joined recently as a PhD student. As part of a collaboration with Prof. B. R. S. Babu of Calicut University, Veena Sivaram, a student at Calicut, is also involved in TAUVEX related science.

Finally, the coding for the TAUVEX software is being done by 3 software trainees (M. Fayaz, Vaishali Sharan, and Geetha L.) under the supervision of Dr. Rekhesh Mohan. Part of our Institute mandate is to provide training for qualified technical people at the start of the careers and there can be no better or more exciting training than participating in the development of a new space mission.

Of course, there are many scientists from other institutions also involved - some of whom are named in the Science Plan document - but we expect still more involvement upon the launch of the spacecraft when real data are acquired. As mentioned above, one such example is Prof. Gupta who has begun a TAUVEX related project at IUCAA.

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Future Work
It is to be noted that the TAUVEX science group has been extraordinarily productive with a total of 5 refereed publications and several conference papers. This included a considerable amount of preparatory work which is beginning to bear fruit with several more publications to appear shortly. This science work is crucial to the utilization of TAUVEX data and will continue.

There is still a considerable amount of project related work, particularly in the completion of the software development, not just the pipeline but also the archival and analysis programs. Increasing focus will be given to both mission planning and to user and science support, particularly with the hiring of new PDFs.

The IIA TAUVEX team will participate fully in the testing and integration of the TAUVEX instrument with the GSAT-4 spacecraft at ISAC and will support all activities through launch and, of course, flight and the collection of the science data.

Finally, we recognize that the true measure of TAUVEX success can only come through the participation of the Indian science community and we will continue to hold workshops including actively recruiting University faculty and students, where the future of Indian astronomy must lie.

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Acknowledgements
Many people have contributed to the success of the TAUVEX project. Dr. K. Kasturirangan and Dr. P. Goel were instrumental in ensuring that TAUVEX was considered for flight. Mr. V. K. Kaila, Dr. V. K. Agrawal and the TAUVEX project team at ISAC have put in extra work to clear all the TAUVEX interfaces with GSAT-4. Dr. P. Sreekumar has also helped in many TAUVEX issues as have Dr. Chakravarty and Mr. Chandrasekhar at ISRO HQ.

There are many people at IIA who have been involved in different parts of the TAUVEX mission and have provided encouragement at different phases including N. K. Rao, A. K. Pati, H. C. Bhatt, D. C. V. Mallik, B. R. Prasad, and S. Sengupta.

In addition, many of our colleagues from other institutions have supported TAUVEX in many ways and we hope they will be involved increasingly in the future.

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