missions versus funding of new missions. During its deliberations the committee attended to the general principle of balance in developing its recommended prioritization of projects within the NASA Astrophysics Division program during the coming decade.
In terms of mission size balance, the committee values the impressive science value per dollar achieved with a healthy Explorer program, so much so that an enhancement to the Explorer program is its second-ranked large space project recommendation in Chapter 7. Likewise, the committee recommends strong support for the suborbital and balloon programs. Apart from providing a high science return, these smaller-scale activities provide opportunities for university-led projects, which in turn train future instrumentalists and leaders in space astrophysics and maintain a strong skill base outside the NASA centers. They also provide testbeds for future technologies and vital science inputs for planning future larger missions. These same considerations motivate the committee’s recommendations for maintaining or enhancing the support for non-mission specific technology development.
As discussed in Chapter 3, international collaborations are becoming a major factor in current and future missions. Nearly all of the large space-based projects recommended in Chapter 7 have some international element. International collaborations can carry administrative, technical (e.g., ITAR), and even political burdens. Overall, however, the committee views this evolution as a means of maximizing science and minimizing redundancy in an era of tight funding.
A final important balance element is between support for the development and operation of missions and the support for the archiving, analysis, and scientific interpretation of the data realized from the missions, including theoretical and computational modeling. Although these activities add up to a minor fraction of total mission costs, funds are often re-appropriated from these categories when costs overrun in other components of the NASA SMD budget. These vital elements of NASA Astrophysics Division funding must be protected from overruns elsewhere.
Based on the recommendations of the 2001 decadal survey, AANM, NSF is currently supporting development of LSST and technology related to a Giant Segmented Mirror Telescope (GSMT), Square Kilometer Array (SKA), and Frequency Agile Solar Radiotelescope (FASR). A desire for healthy balance between future facilities, current facilities, and core activities such as those described in Chapter 5 led the committee to consider evolution in the existing optical and infrared; radio, millimeter, and submillimeter; and solar observatory telescope systems in U.S. ground-based astronomy.