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Impending Wavelength Gaps and Development Timescales for Great Observatories

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Impending Wavelength Gaps and Development Timescales for Great Observatories The Space Astrophysics Landscape 2019 (LPI Contrib. No. 2135) 5060.pdf IMPENDING WAVELENGTH GAPS AND DEVELOPMENT TIMESCALES FOR GREAT OBSERVATORIES S. R. McCandliss1, M. Elvis2, L. Armus3, S. T. Megeath4, and the Working Groups of the SAG-10 Cosmic Origins Program Analysis Group 1Center for Astrophysical Sciences, Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore MD 20118 ([email protected]), 2Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge MA 02138 ([email protected]), 3Spitzer Science Center, California Institute of Tech- nology, Pasadena CA 91125 ([email protected]), 4University of Toledo, Department of Physics and Astronomy, Toledo OH 43606 ([email protected]). Introduction: The panchromatic wavelength cov- Athena? erage of the four original great observatories (GOs), 2032 WFIRST ------------ ? the Hubble Space Telescope (HST), the Chandra X-ray JWST? Observatory, the Compton Gamma-ray Observatory ALMA ELTs CTA LSST (CGO), and the Spitzer Space Telescope (SST), has WFIRST Astro 2020 Astro JWST offered sustained access to wavelengths not accessible 2025 LSST ALMA from the ground and produced stunning synergies of Hubble? Chandra? CTA ------------ XRISM NuSTAR? +2 Explorers scientific advancement for the astronomical communi- SOFIA ty. Recent examples of ground-breaking studies car- The Great Observatories 2020 - Fermi* ried out with the GOs range from the highest redshift Spitzer Hubble Chandra SOFIA (z > 10) galaxies and deep surveys of the early Uni- ALMA Herschel GALEX NuSTAR 2003 WISE <-------- ---------- Swift ---------------------> Explorers verse (e.g., the Frontier Fields [1]), to nearby terrestrial Sun temperature 6 K 6000 K 6 million K exoplanets and potentially habitable worlds around studies: dust, molecules atoms, plasma nuclei Trappist-1 [2], to the merging neutron star EM coun- Space Space access required N Op Far-IR Mid-IR UV X-ray Hard X-ray MeV GeV terpart to GW170817 [3]. IR t 11 15 19 21 23 13 17 log frequency (Hz) In the coming decade the community is facing losses in the panchromatic coverage that we have en- Figure 1: Impending gaps in electromagnetic wave- joyed for a generation. Figure 1 shows the impending length coverage. losses graphically. NASAs Cosmic Origins Program Analysis Group (CO-PAG) has convened a Science Observatory Proposed Decadal Launched Devel-time Cost Cost Green (yrs: (at (2019) Analysis Group (SAG-10) to investigate the impacts of light Proposed - launch) these losses in the coming decade and beyond, and to Launch) identify options for mitigation should they be found to Hubble 1968 1982 1990 23 $4.7G $9.1G be highly consequential. (née LST) (1972) Chandra 1976 1991 1999 23 $1.65G $2.5G The development of the original GOs offers guid- (née AXAF) (1982) ance to future resource needs. They were developed Compton 1977 1982 1991 15 $617M $1.1G over 10-20+ year timescales and spanned a large range (née GRO) of costs-through-launch from ~ $1G to multiple bil- Spitzer 1979 1991 2003 25 $720M $0.99G lions, as summarized in Table 1; costs typically asso- (née SIRTF) (1972) ciated today with probe and flagship class missions. This flexibility of scale is desirable as different tech- nologies may offer order-of-magnitude gains in differ- Table 1: Summary of Development Timescales and ent bands at greatly different cost. The long lead-time Costs. from conception to launch emphasizes the need to plan now even for the 2030s. References: [1] Mann A. W. and Ebeling H. (2012) MNRAS, 420, 2120-2138. [2] Bourrier V. et al. (2017), AJ, 154:121. [3] Abbott B. P. (2017) ApJL, 848:L12. .
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