3 p.International audienceC2PU stands in french for "Centre Pédagogique Planète Univers" (Planet and Universe Pedagogic Center). It is a project both for pedagogic and research purposes. It relies on the renewal of two 1-meter diameter telescopes. These two telescopes were earlier coupled as part of an interferometric instrument called SOIRDETE (for "Synthèse d'Ouverture en Infra Rouge avec DEux Telescopes"), described in Rabbia et al. 1990

Abe, Lyu

Bendjoya, Philippe

Rivet, Jean-Pierre

HAL-INSU

C2PU: 1-Meter Telescopes for the GAIA-FUNPhilippe Bendjoya, Lyu Abe, Jean-Pierre RivetTo cite this version:Philippe Bendjoya, Lyu Abe, Jean-Pierre Rivet. C2PU: 1-Meter Telescopes for the GAIA-FUN. Institut de Me´canique Ce´leste et de Calcul des Ephe´me´rides (IMCCE). Workshop GaiaFun-SSO : follow-up network for the Solar System Objects, Nov 2010, Paris, France. 1 vol.,149 p., 2011. <hal-00602514>HAL Id: hal-00602514http://hal.upmc.fr/hal-00602514Submitted on 22 Jun 2011HAL is a multi-disciplinary open accessarchive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come fromteaching and research institutions in France orabroad, or from public or private research centers.L’archive ouverte pluridisciplinaire HAL, estdestine´e au de´poˆt et a` la diffusion de documentsscientifiques de niveau recherche, publie´s ou non,e´manant des e´tablissements d’enseignement et derecherche franc¸ais ou e´trangers, des laboratoirespublics ou prive´s.7a); but the southern observatories contribute 25% of the discoveries (Fig. 7b). The decrease in the asymmetry is mainly due to the prolific activity on a single discoverer in the southern hemisphere: Robert McNaught.2. Follow-up and search activities at Observatorio Astronómico Los Molinos, UruguayThe Observatorio Astronómico Los Molinos (OALM) is located in Uruguay, South America. The geographical coordinates are: Latitude 34º 45' 20" S, Longitude 56º 11' 23" W , Altitude 130 m. It has the IAU code 844. OALM was inaugurated in 1994 and belongs to the Innovation, Sciences and Technology Office (DICYT) of the Culture and Education Ministry (MEC). It is also supported by the Department of Astronomy of Universidad de la República.It is the only professional observatory in Uruguay. Since it is located close to Montevideo, the light pollution issues are worrisome. This fact leads us to build another observing facility in the country side, the Observatorio de Aiguá in Maldonado (250 km from Montevideo). The scientific activity of OALM is focused on Solar System Minor Bodies (i.e. comets and asteroids), being one of the few observatories dedicated to this topic in the southern hemisphere. We observe recently discovered asteroids (i.e. the confirmation task), or already discovered ones that need further observations (i.e. the astrometric follow-up). The maininstruments are CCD-equipped 35 and 46cm telescopes used for astrometrical and photometrical programs. Also in the OALM facilities are placed other observing instruments with their respective domes that belong to amateur astronomers. Detail information about our facilities can be found in our institutional website: http://oalm.astronomia.edu.uy.We concentrate our follow-up observations on objects in the southern sky, as it is shown in Fig. 8a. The histogram of the distribution of reported magnitudes peaks at V~16 (Fig. 8b), but we can reach magnitudes down to 18.5, especially, after some instruments improvements, in the last year. The mean residual and standard deviation of the astrometric observations reported by OALM are: in right ascension µRA= -0.013”, σRA = 0.78”; in declination µDec= -0.066”,σDec= 0.92”, respectively.ConclusionThe north-south asymmetry in the discovery and follow-up of asteroids is a problem that reflects the economic and scientific development of the world. An all-sky survey like Gaiawould help to mitigate this problem. Nevertheless, much effort should be put in the follow-up activities in the southern hemisphere after the discoveries by Gaia.Fig. 8 – a) Number of asteroid reports to the MPC in the period 2005-2010 from OALMclassified respect to the Declination of the data. b) Histogram of the distributionof the reported magnitudes.a) b)C2PU: 1-Meter Telescopes for the GAIA-FUNBendjoya, Ph.1, Abe, L1, Rivet, J.P.21 Laboratory H. Fizeau, Université de Nice Sophia-Antipolis, Observatoire de la Côte d’Azur, CNRS-UMR 6525, Campus Valrose 06108 Nice cedex 2 France2 Laboratory Cassiopée, Université de Nice Sophia-Antipolis, observatoire de la Côte d’Azur,CNRS-UMR 6202, Boulevard de l’Observatoire, B.P. 4229 F-06304 NICE Cedex 4 Presentation C2PU stands in french for “Centre Pédagogique Planète Univers” (Planet and Universe Pedagogic Center). It is a project both for pedagogic and research purposes. It relies on the renewal of two 1-meter diameter telescopes. These two telescopes were earlier coupled as part of an interferometric instrument called SOIRDETE (for “Synthèse d’Ouverture en Infra Rouge avec DEux Telescopes”), described in Rabbia et al. 1990.These two telescopes are located in southern France, 50 km away from the city of Nice, on the so-called “Plateau de Calern”. The coordinates are 6° 55′ 22″ East in longitude, 43° 45′ 14″North in latitude and 1261 m in elevation. The average number of clear nights per year is 200 and the sky background level ranges from 20.7 to 21 magnitudes per square arc-seconds.The project is supported by the “Observatoire de la Côte d’Azur” (OCA), the University of Nice Sophia-Antipolis (UNS) and the “Collège de France” (CdF). The two Cassegrain telescopes are planned to be renewed in two phases. The first one which has begun in September 2010 involves the shaping and polishing of a 1-meter primary mirror for the EastTelescope (E-Tel), out of a Zerodur® blank provided by OCA. This phase should end late 2011. During this polishing operation by D. Vernet from CdF, the refurbishing of the mechanical structure of the telescope is undertaken. In parallel, we are designing the hardware and software for the remote control of E-Tel through Internet The second phase will begin in 2012 and will concern the second 1-meter telescope, the West-telescope (W-Tel). The E-Tel is planned to have two different focus configurations: an F/3 prime focus for wide field imaging, and a Cassegrain F/12.5 focus. Switching from one configuration to the other will only consist in plugging or unplugging an opto-mechanical module. The telescope will bedriven by an automatic controller, accessible through an internet interface, to allow for remote observations. The F/3 focus will be equipped with a SBIG STX-16803 CCD camera. This will lead to a pixel scale of 0.6’’/pix and a 40×40 arcmin field of view. The 20th magnitude is expected to be reachable in a 1 min exposure. This configuration will be dedicated to wide field imagery and transit photometric surveys. The F/12.5 focus will receive a SBIG ST8XME CCD camera. This will provide for a 3.8×2.5 arcmin field of view, with a pixel scale of 0.15 arcsec/pix. Magnitude 17 is expected to be reachable in 1 minute exposure. This configuration will be used for spectroscopy and/or polarimetry. The characteristics of the spectrometer and of the polarimeter are currently under discussion. The W-Tel with its F/35 “coudé” focus should be available late 2012. The focal image will be delivered on an optical bench, at a fixed point, regardless of the position of the astronomical target. On this optical bench, all kind of focal instrumentation will be welcomed, such as a deformable mirror and a wave front sensor for an adaptive optic system, a differential speckle interferometer, a spectrometer of a polarimeter. With a SBIG ST8XME CCD camera, this 81configuration would lead to a 1.3×1 arcmin field of view, with a pixel scale of 0.05 arcsec/pix. Magnitude 15 should be reachable in 1 minute exposure.The observation will be performed essentially by supervised master students, but in case of alert during a non pedagogic period, dedicated staff will be reachable for an in situ observation and/or remote session assistance. Fig. 1 – from up left to down right: a) The roadmap from Nice International Airport to “Plateau de Calern”, b) the two C2PU domes, c) East telescope (E-Tel), d) polishing and curvature control of the 1-meter Zerodur® blank.Table 1 – Summary of the C2PU characteristics and receptorsInstrument                    1                  2                 3 Name T_E_F3=GROUCHO T_E_F12=HARPO T_W_F35=ZEPPO Refractor/Reflector reflector reflector reflector Focal length(m) 3 12.5 35 Diameter (m) 1 1 1 Comments GROUCHO and/or HARPO will be remotely accessible Receptor Type/name SBIG STX‐16803 SBIG ST8XME SBIG ST8XME Pixel size (arcsec/pix) 0.6’’/pix 0.15’’/pix 0.05’’/pix Field Of View (arcmin) 40×40’ 3.8×2.5’ 1×3⋅1’ Limiting magnitude 20 in 1 minute exposure 17 in 1 minute exposure 15 in 1 minute exposure 82Gaia-Fun-Sso Workshop Proceedingsconfiguration would lead to a 1.3×1 arcmin field of view, with a pixel scale of 0.05 arcsec/pix. Magnitude 15 should be reachable in 1 minute exposure.The observation will be performed essentially by supervised master students, but in case of alert during a non pedagogic period, dedicated staff will be reachable for an in situ observation and/or remote session assistance. Fig. 1 – from up left to down right: a) The roadmap from Nice International Airport to “Plateau de Calern”, b) the two C2PU domes, c) East telescope (E-Tel), d) polishing and curvature control of the 1-meter Zerodur® blank.Table 1 – Summary of the C2PU characteristics and receptorsInstrument                    1                  2                 3 Name T_E_F3=GROUCHO T_E_F12=HARPO T_W_F35=ZEPPO Refractor/Reflector reflector reflector reflector Focal length(m) 3 12.5 35 Diameter (m) 1 1 1 Comments GROUCHO and/or HARPO will be remotely accessible Receptor Type/name SBIG STX‐16803 SBIG ST8XME SBIG ST8XME Pixel size (arcsec/pix) 0.6’’/pix 0.15’’/pix 0.05’’/pix Field Of View (arcmin) 40×40’ 3.8×2.5’ 1×3⋅1’ Limiting magnitude 20 in 1 minute exposure 17 in 1 minute exposure 15 in 1 minute exposure ConclusionC2PU will offer as soon as late 2011 an observation facility, perfectly suited for GAIA-FUN. Indeed, it will allow for both an easy follow-up of moving object through its wide field F/3 focus, and efficient physical parameters measurements through a range of focal instruments, to be fitted to the F/12.5 and F/35 focuses. The remote control through Internet and the supervised student manpower will allow for a fast reactivity and extensive time coverage.ReferencesRabbia Y., Mékarnia D., Gay J. :1990 Infrared interferometry at Observatoire de la Côte d’Azur, France, in Infrared Technology XVI; Proceedings of the Meeting, San Diego, CA, July 11-13, 1990 (A92-21426 07-35). Bellingham, WA, Society of Photo-Optical Instrumentation Engineers, p. 172-182.83Bendjoya P. et ali

C2PU: 1-Meter Telescopes for the GAIA-FUN

Abstract

Similar works

Full text

Available Versions

HAL-INSU