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Laboratory Astrophysics
As described in Chapter 5, support and infrastructure for laboratory astrophysics are eroding both
in the National Laboratories and in universities. Yet the current Herschel mission, the next decade’s
JWST and ALMA, and the future IXO will provide unprecedented spectroscopic sensitivity and
resolution, enabling new quantitative diagnostics of the interstellar medium, star-forming regions, and hot
plasmas in a wide variety of astrophysical contexts. With these improvements in spectroscopic
capabilities in the submillimeter, infrared, and X-ray regions, extracting quantitative information will in
many cases become limited by available knowledge of atomic and molecular transition data and cross
sections. Further, detailed understanding of magnetized plasmas, the formation of molecules, and
complex chemical reactions at a level that can only be obtained experimentally is of central importance to
interpreting data from these missions.
It is recommended that NASA, in coordination with DOE, assess the level of funding available
for laboratory astrophysics through the APRA program relative to the requirements of its current and
future spectroscopic missions. Funding through APRA that is aimed at mission-enabling laboratory
astrophysics should be augmented at a level recommended by this scientific assessment. While the costs
of obtaining the data that will be needed in the coming decade are difficult to estimate, an increase of 25
percent over the current budget, or a notional budget increment of $20 million over the decade, may be
required.
Suborbital Program
NASA-supported balloon and rocket experiments, known collectively as the suborbital program,
enable science, develop technology, and provide an invaluable training ground (Figure 7.7). Many
highly successful Explorer missions, such as GALEX and WMAP, were preceded by balloon-borne
observations and technology demonstrations.
Recent efforts by NASA management have halted the long erosion of the core suborbital and
R&A programs, out of which balloon and rocket payload development is funded, and these programs
have largely been restored. However, additional resources are needed to support the high-priority science
areas identified by this survey. NASA should investigate and, if practical and affordable, implement the
orbital sounding rocket capability described by NASA’s Astrophysics Sounding Rocket Assessment
Team, which would provide a few thousand times more observing time than normal sounding rocket
flights, greatly increasing the science that can be accomplished from rockets. The priority in the balloon
program should be to increase the launch rate and develop new payloads. The ultralong-duration balloon
(ULDB) program is attractive, because it provides about a factor-of-three more observing time than
Antarctic long-duration balloons (LDBs) as well as mid-latitude long-duration flights, but it is expensive.
One of this survey’s priority science areas, CMB, along with related dark-matter and cosmic-ray detection
experiments, has primary requirements for frequent access and increased total observing. If it is more
cost-effective per observing day to expand the LDB program and improve its facilities and recovery
reliability, then this should have the highest priority.
To increase the launch rate by about 25 percent, it is recommended that the R&A program be
augmented by $5 million per year to accommodate the selection of additional balloon and rocket
payloads. In addition, $10 million per year will be needed to support the additional launches and
improvements in infrastructure.
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
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