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Gemini Observatory Colina El Pino S/N La Serena Chile Jrroy@Gemini.Edu Gemini Observatory Colina el Pino S/N La Serena Chile [email protected] Contents 1. Introduction 2. Gemini science niches for the ELTs 3. Imaging of exoplanetary systems, a pathfinder for exploring outer worlds 4. Mapping the cores of galaxies and meshing IFU datacubes 5. GRBs at z > 7: signposts for proto-galaxies 6. “Queue” observing and re-engaging astronomers with their science machines 7. Will E-ELTs be the last machines? No! 8. Reflections on partnership and lessons learned from Gemini 9. References Science with the 8-10m telescopes in the era of the ELTs and the JWST 78 libroGTC_ELTF061109.indd 78 12/11/2009 12:35:26 Jean-René Roy Gemini Observatory Gemini as Pathfinder for 21st Century Astronomy “We have been going round a workshop in the basement of the building of science. The light is dim, and we stumble sometimes. About us is confusion and mess which there has not been time to sweep away. The workers and their machines are enveloped in murkiness. But I think that something is being shaped here – perhaps something rather big. I do not quite know what it will be when it is completed and polished for the showroom. But we can look at the present designs and the novel tools that are being used in its manufacture; we can contemplate too the little successes which make us hopeful.” (A. Eddington 1933) Science with the 8-10m telescopes in the era of the ELTs and the JWST 79 libroGTC_ELTF061109.indd 79 12/11/2009 12:35:27 Abstract Synergies between new ground- and space-based observatories are promises for the role of 8- to 10 meter telescopes, with a generous discovery space that still lies ahead in the com- ing decade. I explore examples of science areas where our largest ground-based telescopes can build up a precious inventory of targets and fields to be probed deeper with the coming Extremely Large Telescopes (ELTs). The operational model of the Gemini telescopes is domi- nated by queue/service observing. A visiting and interaction model that helps to re-engage astronomers with their “machines” is presented and discussed. I surmise that ELTs may not be the last generation of single aperture ground-based optical-infrared telescopes. The recent history of radio astronomy–going in the direction of un-filled reconfigurable arrays of antennae– points to the increasing importance of interferometry in optical/infrared astronomy. Finally, I share some candid lessons learned from the Gemini partnership that deal with operational issues and governance. Science with the 8-10m telescopes in the era of the ELTs and the JWST 80 libroGTC_ELTF061109.indd 80 12/11/2009 12:35:27 1. Introduction In late November and early December 1609, Galileo Galilei observed the sky with a small telescope of his own design and fabrication. Its aperture (30-50 millimeters) was tiny. To minimize aberrations, he had sized down the aperture with a diaphragm. Compared to the giant telescopes of today, his apparatus was extremely modest. Still, the discoveries that it enabled were staggering and rocked the 17th century scholarly world. The invention (a rather complex and debated topic) and early use of the telescope had a dramatic effect on the course of astronomy. The subsequent application of the telescope to the whole electromagnetic spectrum is proof of the success and power of this versatile observing tool. Today’s telescopes have become giant hi-tech machines run by sophisticated organizations. It is significant that the Gran Telescopio Canarias (GTC) is being dedicated almost exactly four centuries after Galileo stupendous achievement. In the middle of the coming decade, the infrared James Webb Space Telescope (JWST) will start operating. The Hubble Space Telescope (HST) will likely have been decommissioned. As HST did, JWST will have a huge scientific impact and also influence the way ground-based observatories operate and follow up on their discoveries. Synergies with the radio millimeter Atacama Large Millimeter Array (ALMA) expected to be in full operations in 2012 will be enormous. Large dedi- cated survey telescopes (Pan-STARRS (Panoramic Survey Telescope & Rapid Response System) 1&2, VISTA (Visible and Infrared Survey Telescope for As- tronomy), VST (VLT Survey Telescope) or Subaru Telescope/HyperSuprimeCam) now coming on-line will be very powerful for finding new objects and transients that will require spectroscopic follow up on 8 to 10 meter telescopes. The Large Synoptic Survey Telescope (LSST, still not funded, and unlikely to be so within a few years) may start operations on Cerro Pachón, Chile around 2018. Be- cause of its mission and capabilities, this powerful survey facility will put huge Science demands in terms of spectroscopic follow-up. Robust “Point-and-shoot” capabilities with the 8-10m will become essential for the next generation of ground-based telescopes. Interest- telescopes in the era ingly, the GTC is located at a meridian that will increase coverage of the diurnal of the ELTs and the time domain from both hemispheres. JWST 81 libroGTC_ELTF061109.indd 81 12/11/2009 12:35:27 Large gains made by the current 8 to 10 meter aperture telescopes will not be at- tributable to aperture size but successful active and adaptive optics systems that have demonstrated that the turbulent structure of the atmosphere is amenable to analysis and correction (Mountain 2000; Smith 2009). Also, new developments in spectrograph design (single slit, multi-object, integral field unit, immersed gratings, cryogenic system, detector technology etc.) for all wavelengths have equipped as- tronomers with enhanced tools that would have been dreams a few decades ago (see, for example, the review of European Southern Observatory (ESO) optical spectro- graphs by Dekker 2009). Any Extremely Large Telescope (ELT) with fully-operational instruments will come into full science operation only during the first half of the 2020s. Hence, the current generation of 8 to 10 meter telescopes have a ten-year window of scientific “freeway” ahead with a generous discovery space. 2. Gemini science niches for the ELTs The Gemini telescopes (Figure 1 and 2) built and commissioned during the 1990s, started science operations in late 2000 (Gemini North) and 2001 (Gemini South). The two 8 meter optical/infrared telescopes are separated by 11,000 kilometers and present some interesting technical, and logistical challenges. They have been under steady operation for about eight years (as of mid-2009) and their lifetimes are likely to overlap with the next generation of 20 to 42 meter behemoth telescopes. What can the role be for telescopes such as Gemini in the preparatory and transi- tional era for these new machines? Among several possible areas Gemini, and oth- ers, can lay the groundwork for ELT exoplanets research, fine-scale spectroscopic mapping of galaxy cores and gamma-ray bursts study as sites of first light objects. 3. Imaging of exoplanetary systems, a pathfinder for exploring outer worlds Everyday the field of exoplanet imaging research is progressing in ways and with jumps that appeared impossible yesterday. The current trends in discovery will continue to be driven by the massive efforts from space and ground facilities (now including several amateur programs that monitor planetary transits). The techniques of reflex motion and primary/secondary eclipsing by planetary companions will continue to reveal hundreds of planets, from a few Earth masses to that of several Jupiter, from the rocky/watery smaller bodies to giant gaseous, brown-dwarf-like objects and perhaps even stranger objects. However, we now have the means to go beyond these baby-steps with direct imaging of exoplanetary systems. Science with the 8-10m telescopes in the era of the ELTs and the JWST 82 libroGTC_ELTF061109.indd 82 12/11/2009 12:35:27 Figure 1. View of the Gemini North telescope with its 12-Watt solid-state laser beam propagating for laser guide star adaptive optics observations. Science with the Figure 2. View of the Gemini South dome (from inside) and telescope. The 8-10m Near-Infrared Coronagraphic Imager (NICI) is the instrument visible attached telescopes in the era to the Cassegrain instrument support structure. Three other instruments of the ELTs (not visible) are mounted on the remaining ports. and the JWST 83 libroGTC_ELTF061109.indd 83 12/11/2009 12:35:33 Figure 3. The exoplanetary system of nearby star HR8799 as viewed in K-band by Gemini North NIRI infrared imager. The system was discovered using the adaptive optics system on the Gemini North and W.M. Keck telescopes. (Credit: Marois et al. 2008) It is up to the current genera- tion of large 8 to 10 meter telescopes equipped with very high contrast adaptive optics imagers and spectrographs to build an “atlas” or inventory of exoplanet systems. These will be probed by imaging to fur- ther depths by the ELTs a de- cade from now. Indeed, sys- tems now on-line at Gemini (NICI), Subaru (CIAO), Keck and VLT (NACO) are capable of building a large inventory of known exoplanetary systems and and lead- ing to a grasp on the nature of extra-solar planets (Figure 3). The Gemini Planet Imager (Macintosh et al. 2006) and ESO/SPHERE (Beuzit et al. 2006, 2008) will take this to the next step by boosting our ability to perform spectroscopy on these systems. A new era of characterizing the physical, chemical and biological states of exoplan- ets has already begun. While many parameters will require JWST, ALMA and ELT capabilities, the current 8 to 10 meter-class telescopes, equipped with adequate in- strumentation are capable of searching for key but simple bio-signatures or biomark- ers (such as H2O, O2 or O3 and the “spectral edge” of vegetation that indicates plant cover) in well-identified exoplanetary bodies.
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