A Vigorous Explorer Program

Martin Elvis; Matthew Beasley; Roger Brissenden; Supriya Chakrabarti; Michael Cherry; Mark Devlin; Jerry Edelstein; Peter Eisenhardt; Paul Feldman; Holland Ford; Neil Gehrels; Leon Golub; Herman Marshall; Christopher Martin; John Mather; Stephan McCandliss; Mark McConnell; Jonathan McDowell; David Meier; Robyn Millan; John Mitchell; Warren Moos; Steven S. Murray; John Nousek; William Oegerle; Brian Ramsey; James Green; Jonathan Grindlay; Philip Kaaret; Mary Elizabeth Kaiser; Lisa Kaltenegger; Justin Kasper; Julian Krolik; Jeffrey W. Kruk; David Latham; John MacKenty; Amanda Mainzer; George Ricker; Stephen Rinehart; Suzanne Romaine; Paul Scowen; Eric Silver; George Sonneborn; Daniel Stern; Mark Swain; Jean Swank; Wesley Traub; Martin Weisskopf; Michael Werner; Edward Wright

arXiv · 0911.3383

A Vigorous Explorer Program

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Abstract

Explorers have made breakthroughs in many fields of astrophysics. The science from both these missions contributed to three Nobel Prizes - Giacconi (2002), Mather, and Smoot (2006). Explorers have: marked the definitive beginning of precision cosmology, discovered that short gamma-ray bursts are caused by compact star mergers and have measured metalicity to redshifts z>6. NASA Explorers do cutting-edge science that cannot be done by facility-class instruments. The Explorer program provides a rapid response to changing science and technology, to enable cutting-edge science at moderate cost. Explorers also enable innovation, and engage & train scientists, managers and engineers, adding human capital to NASA and the nation. The astrophysics Explorer launch rate now being achieved is 1 per 3 years, and budget projections are in the $150M/year range for the next five years. A newly Vigorous Explorer Program should be created to: 1. Reach the long-stated goal of annual astrophysics launches; 2. Find additional launch options for Explorers and actively encourage cost savings in launchers and spacecraft, such as new commercial vehicles and innovative partnerships. 3. Mitigate risk via stronger technical development and sub-orbital programs, and through longer, more thorough, Phase A programs, potentially reducing the need for a 30% contingency; 4. Strive to protect the funding for missions that have reached Phase B, to prevent significant launch slips and cancellations, with a goal of 4 to 5 years from Phase B to launch; 5. Review the project management procedures and requirements to seek cost reductions, including the risk management strategy and the review and reporting process; 6. Review and possibly modify the cost caps for all Explorer classes to optimize scientific returns per dollar. [ABRIDGED]

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Martin Elvis, Matthew Beasley, Roger Brissenden, Supriya Chakrabarti, Michael Cherry, Mark Devlin, Jerry Edelstein, Peter Eisenhardt, Paul Feldman, Holland Ford, Neil Gehrels, Leon Golub, Herman Marshall, Christopher Martin, John Mather, Stephan McCandliss, Mark McConnell, Jonathan McDowell, David Meier, Robyn Millan, John Mitchell, Warren Moos, Steven S. Murray, John Nousek, William Oegerle, Brian Ramsey, James Green, Jonathan Grindlay, Philip Kaaret, Mary Elizabeth Kaiser, Lisa Kaltenegger, Justin Kasper, Julian Krolik, Jeffrey W. Kruk, David Latham, John MacKenty, Amanda Mainzer, George Ricker, Stephen Rinehart, Suzanne Romaine, Paul Scowen, Eric Silver, George Sonneborn, Daniel Stern, Mark Swain, Jean Swank, Wesley Traub, Martin Weisskopf, Michael Werner, Edward Wright. 2009-11-17. A Vigorous Explorer Program. https://arxiv.org/abs/0911.3383

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