In the spring of 2003, I wrote an article that described the experiences and impressions of my first six months as the NRAO Director. Now, twenty-one months later, as I am in my third year at the NRAO, this second installment of the Director’s perspective is long overdue. My tenure as Director so far has been fascinating and always humbling. Owing to the remarkable range of responsibilities undertaken by the Observatory, my schedule continues to be extremely busy, but my enthusiasm for the bright future of astronomy and the NRAO remains very high.
The Atacama Large Millimeter Array (ALMA) is currently the world’s largest ground-based astronomy facility construction project, especially now that our Japanese colleagues have joined Europe and North America in this international project. ALMA is also the NRAO’s most visible project. Its success is essential for the future of ground-based radio astronomy and the long-term health of the astronomical community in the U.S. and the rest of the world. Civil construction at the Atacama site in Chile has started in earnest, and the complex antenna procurement process is in progress. Hardware and software subsystems are being prototyped, reviewed, and tested in the prototype system integration. ALMA demands much of the NRAO and its people, and the Observatory is responding to the challenges of this technically complex and high-profile international collaboration.
Planning is also underway for the North American ALMA Science Center (NAASC) that will be housed in the Observatory’s recently renovated and expanded Charlottesville facilities. The NAASC will support the scientific use of the array by the North American (United States and Canada) astronomical community. NAASC staff will assist users in proposal preparation and submission, organize proposal reviews, prepare observing blocks and assure data acquisition, maintain pipeline data processing and the data archive, and also provide support in the analysis phases of ALMA observations. The NAASC personnel will also organize science meetings, workshops, and schools, sponsor pre-doctoral and post-doctoral programs, and conduct a range of other programs designed to optimize the astronomical community’s scientific use of ALMA. The NAASC will also be responsible for carrying out research and development, as well as the implementation of software and hardware upgrades for ALMA on behalf of North America. An ALMA Town Meeting is scheduled at the 205th American Astronomical Society Meeting in San Diego.
The Expanded Very Large Array (EVLA) is another cornerstone of ground-based astronomy's future that brings powerful new capabilities to the community for research. Though it is built on the foundation and infrastructure of the Very Large Array (VLA), the EVLA is much more a new facility than simply an upgrade of an existing facility. Phase I of the EVLA Project, now in its fourth year, will improve the array’s sensitivity by an order of magnitude, and the second phase of the project, when funded and built, will achieve an order of magnitude improvement in resolution. Phase I of the EVLA is making very good progress. “First light” was achieved on the first retro-fitted antenna last spring, and first fringes were achieved using this antenna as an element of the VLA last fall. The proposal for Phase II of the EVLA was submitted to the NSF in April 2004 and is currently undergoing peer-review.
As it builds for the future,the Observatory continues to enable forefront research for the astronomical community by operating and continually improving the Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, the extraordinarily productive VLA in New Mexico, and the ten-element Very Long Baseline Array (
To borrow a phrase from one of our colleagues, the GBT is “scientifically flourishing.” Recent GBT scientific results include the detection of at least 17 new pulsars in one beam-pointing at the globular cluster Terzan 5, the detection of HCN at z = 2.4, and the identification of small-scale structure in the HI halo of the Milky Way. The GBT will also provide unique capabilities as its operation is extended to high frequencies up to ~115 GHz. It has already achieved very good efficiency at 43 GHz during the winter of 2003/2004, and new instrumentation is under construction to exploit the sensitivity and resolution at the higher frequencies. Also worth noting is that the Observatory’s methodical analyses and tests of the GBT azimuth track has yielded a retrofit plan that we have high confidence will correct the premature wear problems.
The VLA, which was originally designed to work up to 22 GHz, detected and mapped the CO emission at 46 GHz from the highest known red-shift quasar J1148+5251. This feat of probing galaxies and quasars in the Epoch of Re-ionization was unimaginable only a few years ago. It also highlights the enormous scientific possibilities that will come with the completion the EVLA. Through careful planning, the NRAO is aiming to operate the VLA continuously during the entire construction period of the EVLA. After the antennas have been retrofitted, they will be brought back continually as elements of the array until the EVLA is completed. Similarly, the new WIDAR correlator will be brought into operation in stages. After a subset of the new is installed, early science done with the partial EVLA will already have significantly improved performance over the current VLA.
The VLBA is currently the only operating facility in the world dedicated full-time to VLBI. Last year, the Haystack Observatory and the NRAO jointly commissioned a study of future U.S. VLBI development. The resulting Taylor-Lonsdale Report provides a roadmap to guide future VLBA development. In response to this report, replacement of the VLBA tape-recording systems by Mark 5 hard-disk recorders has started and is scheduled to be complete by the end of 2005. Agreements with other observatories have also made available for VLBI proposals the High Sensitivity Array (HSA) which includes the VLBA, the Arecibo telescope, the Effelsberg 100m telescope, the phased VLA, and the GBT . The sensitivity of the HSA has generated a significant increase in the number of VLBA proposals. In addition, pipeline-processing for the more routine VLBA observations is now available.
A new application for the VLBA is its use in spacecraft navigation, providing high-precision angular tracking of spacecraft. In close collaboration with NASA and ESA, the VLBA's capabilities are being applied in a manner that benefits both astronomy and space science.
In the last two years, the Observatory has worked to enhance its interaction with university and other research organization. The new Division of Scientific and Academic Affairs as the focal point for such activities. The enhanced Jansky Fellowship Program, for example, now permits these fellowships to be held at any NRAO site, U.S. university or research organization, providing outstanding research opportunities for young astronomers, on par with those available through the Hubble, Chandra, and Spitzer Fellowship Programs. Another NRAO program supports astronomical research at the GBT by offering financial support for graduate and undergraduate students at U.S. universities, helping to train new generations of astronomers. The Observatory has seen excellent community response to this GBT program and hopes to initiate a similar program for the VLA and VLBA, funding permitting. The Observatory also encourages increased interaction of the astronomical community with NRAO scientific staff through its Visitors Program, which sponsors short- and long-term visits, summer visits, and sabbatical leaves.
The NRAO has also been actively pursuing collaboration with university and other research groups to build forefront instruments for use on NRAO telescopes. Current examples include the Caltech digital radiometer, the Penn/Goddard Bolometer Array Camera, and instruments being proposed for funding, including Zpectrometer (University of Maryland) and PAPER (UC Berkeley.) On a larger scale, NRAO staff members are working with university groups to develop a new consortium and a proposal to build the Frequency Agile Solar Radio-telescope (FASR). Directly or indirectly, many NRAO staffmembers are also involved in the planning and design studies for the Square Kilometre Array (SKA)
The remarkable range of activities undertaken by the Observatory is possible only because of the breadth and depth of the staff’s expertise and their devotion to the NRAO missions and the astronomical community. I am impressed on a daily basis by the talent and dedication of the NRAO staff in West Virginia, New Mexico, Arizona, Virginia, Chile, and elsewhere. As I noted in the April 2003 Newsletter, a symphony makes great music only if all its musicians play well together and, similarly, the NRAO must function well as “one Observatory.” In reviewing the past two years in my mind’s eye, it is gratifying to see the concrete evidence of the positive change this approach has brought to the NRAO. Communication and coordination across the Observatory continue to improve among our far-flung staff and facilities.
This improvement has been especially noticeable in software development. Software development is now driven specifically by the needs of ALMA, EVLA, GBT, and the overall goal of end-to-end user support (from proposal submission to data archive). The Observatory has established mechanisms to ensure all these project-driven efforts are coordinated Observatory-wide to optimize efficiency and effectiveness. Close attention is required to assure the success of this very important and challenging effort within the NRAO.
There is, of course, a great deal more to do and the NRAO must continue to evolve to meet the challenges of the future. Over the past several years, the Observatory has been improving its management practices to deal with the significant increase in scope of its responsibilities. These efforts have included the establishment of the NRAO Program Management Office (PMO) to provide modern tools for project management, provide accurate cost and schedule data for our entire portfolio, and organize monthly Observatory-wide program reviews. Another important development has been the successful revision of the Scientific Staff Policy, clarifying the career paths and responsibilities of NRAO scientists, optimizing the impact of their expertise and experience on the Observatory’s missions.
Assessing radio astronomy and the NRAO from the vantage point of January 2005, I see a bright future, but also complexity and challenges, including an uncertain and difficult funding environment. Not surprisingly, the U.S. federal deficit is creating political friction and financial pressures that seem certain to constrain budgetary growth for U.S. astronomy in the near-term future, especially in the National Science Foundation which funds the NRAO and ground-based astronomy. Nevertheless, despite these trials of the moment, this is an era of great opportunity, and there is much to celebrate in the astronomical community.
The NRAO staff is proud of what they have accomplished and welcome what will undoubtedly be an equally challenging future. They are forward-looking and continually striving to enable the broadest range of research for all astronomers.