LVII Congresso SAIt Bologna, 7-10 maggio 2013 CHEOPS stato, problemi, opportunità Isabella Pagano on behalf of the CHEOPS Italian Team ESA s first small mission
ESA small missions requirements! Science! top rated science in any area of space science! Cost! total cost < 150 M! cost to ESA: not to exceed 50 M! Schedule! developed and launched within 4 years (end of 2017)! call issued! March 3, 2012! proposal due! June 15, 2012! mission selection! October 19, 2012! mission adoption! Feb 2014! launch! 2017!
Name! Primary science goal! Targets! Mission summary! CHEOPS! (CHaracterizing ExOPlanet Satellite)! Measure the radius of planets transiting bright stars to 10% accuracy! Known exoplanet host stars with a V-magnitude < 12.5 anywhere on the sky! Wavelength! Visible range : 400 to 1100 nm! Telescope! 707 cm 2 effective aperture reflective on-axis telescope (30 cm )! Orbit! LEO sun-synchronous, LTAN 6am, 620-800 km! Lifetime! Type! 3.5 years! S-class!
Targets: Bright stars apparent magnitude of star 16.0 14.0 12.0 10.0 8.0 6.0 Kepler planets NGTS CHEOPS mass measured by radial velocities ~50 CHEOPS targets ~150-200 CHEOPS targets 1.0 5.0 10.0 Radius planet (REarth)
CHEOPS SCIENCE OBJECTIVES!
Science objectives! 1. Mass-radius relation for planets below the mass of Saturn!
Size & mass distributions of planets orbiting G- and K- type stars. corrected for survey incompleteness for small/low-mass planets Howard, 2013, Science 340, 572
CHEOPS provides direct insights into the structure (e.g. presence of a gaseous envelope) and/or composition of the planet. CHEOPS will improve both the sample size as well as the precision of the measurements.
RV planets known mass Science objectives! 2. New targets for future characterization facilities with spectroscopic capabilities! Transiting planets known size Juicy targets for JWST and EChO! Identification of planets with atmospheres in the 1 10 MEarth regime
Science objectives! 3. Constraints on planet migration paths gas fraction different histories R M
a single planet is allowed to grow in a disc Colours code different fraction of icy planetesimals in the planetary cores. 10 planets are allowed to grow simultaneously For planets in the super-earth to Neptune mass range, the difference in ice content between the two models translates into a difference of ~30% in mean radius. Different migration pattern can be inferred by density measurements.
Science objectives! 4. Energy transport in hot Jupiter atmospheres Optical phase curve of a V=10.5 mag star by Kepler HAT-P-7b Combination of the light reflected by the atmosphere of the planet as well as the thermal emission of the atmosphere. Borucki et al. (2009)
CHEOPS SCIENCE REQUIREMENTS!
High-level Sci Req.: Photometric accuracy for transit detection! Targets from RV campaigns
High-level Sci Req.: Photometric accuracy for transit characterization! Targets from ground based transits search e.g., NGTS
CHEOPS Sky visibility! Total observation time over 1 year [hours] Orbits with more than 50% interruption (less than 50 min of possible observations), due to Earth and Earth stray light constraints, have been discarded. 700 Km altitude orbit The circles are known radial velocity targets, the diamonds are simulated NGTS targets.
CHEOPS ORGANIZATION!
Country! Institutes! Contacts! CH! University of Bern (project lead)! University of Geneva! Swiss Space Center (EPFL)! ETH-Z! Willy Benz, Nicolas Thomas! Didier Queloz! Anton Ivanov! Michael Meyer! Austria! Institut für Weltraumforschung, Graz! Wolfgang Baumjohann! Belgium! Centre Spatial de Liège! Université de Liège! Etienne Renotte! Michaël Gillon! France! Laboratoire d astrophysique de Marseille! Magali Deleuil! Germany! DLR Institute for Planetary Research! DLR Institute for Optical Sensor Systems! Tilman Spohn! Hungary! Konkoly Observatory! Laszlo Kiss! Italy! Portugal! Sweden! Osservatorio Astrofisico di Catania INAF! Osservatorio Astronomico di Padova - INAF! Università di Padova! Centro de Astrofisica da Universidade do Porto! Deimos Engenharia! Onsala Space Observatory, Chalmers University! University of Stockholm! Isabella Pagano! Roberto Ragazzoni! Giampaolo Piotto! Nuno C. Santos! Antonio Gutiérrez! R. Liseau! G. Olofsson! UK! University of Warwick! Don Pollaco! Payload Ground segment
CHEOPS Organization! CHEOPS Project ESA Joint Project Office Joint Management Team ESA/CH decisions excluding payload & science CHEOPS Consortium Science Team Project Scientist ESA Project Office ESA Project Office CH CMC Board CC Coordination Team Instrument Support Science Study Team Science Preparation Launch Services Spacecraft Architect Mission Operations Payload Science Operations Launch campaign Platform Prime AIT RUAG / TBD MOC Instrument Lead Science Ops & Data Centre Subsystems Operations Operations Planning Instrument Handling Data Centre Data Processing Data Archive CHEOPS Project Structure v2.20
Platform! Attitude Control! 3-axis stabilized S/C - one side facing Earth! pointing accuracy < 8 arc sec rms for 10h! Instrument Power! 50 W continuous power,! 70 W peak! Data rate! 1 Gbit/day downlink! Total mass with payload! 200 kg!
Payload - CIS! radiators! outer baffle! structure! (carbon fiber)! baffle tower! focal plane assembly! beam! shaper! secondary! mirror! primary! mirror!
Milestones for the Cheops Payload!
CHEOPS-IT Contributions! Science! Telescope (from optical design to AIV)! Start Trackers (tbc)! ASDC! Malindi (tbc)!
CHEOPS in Italy! q 5 INAF structures! q q q q q OACT (S, P)! OAPD (S, P)! OAPA (S)! OAT (S)! FGG (S)! q Dip. Fis. e Astron. UNIPD (S)! q ASI! q q ASDC (GS)! Malindi (GS)!
Work Breakdown Structure CHEOPS-IT I. Pagano INAF-OACT WP 1000 Project Office I. Pagano INAF-OACT WP 2000 Science Preparation G. Piotto UNIPD WP 3000 Telescope R. Ragazzoni INAF-OAPD WP 1100 Project Management I. Pagano INAF-OACT WP 2100 Science Management G. Piotto UNIPD WP 2200 Target Characterization TBD (AR) UNIPD WP 3100 Project Management I. Pagano INAF-OACT WP 3200 System Engin. S. Scuderi INAF-OACT WP 2300 Observing Strategy Optim. TBD (AR) INAF-OAPD WP 2400 Target Selection I. Pagano INAF.-OACT WP 3300 OD & Tolerances D. Magrin INAF-OAPD WP 3400 Straylight Analysis M. Munari INAF-OACT WP 2500 Synergies Stellar Activity TBD (TD) INAF-OACT WP 3500 Interfaces J. Farinato INAF-OAPD WP 3600 GSE & AIV TBD (TD) INAF-OAPD
Optical Design F/5 Ritchey-Chretien Telescope (0.3 central obstruction) + collimator-camera re-imaging system Focal Plane Mask 320 mm 68 mm ~230 mm Main design drivers are: the compactness of the optical system the capability to reject the straylight the shape of the PSF 400 mm Polychromatic defocused PSF with 30 pixel diameter Magrin et al
Optical Design Back-End Optics Telescope FP Collimator S-FPL51 Camera Intermediate pupil KZFS8 S-FPL51 N-KZFS11 FP Defocused FP 298 mm Several options under study: Different M1-M2 distances è Axicon Holographic diffuser Defocused design Intermediate pupil Collimating beam Diffuser Camera 350 mm 300 mm
CHEOPS-IT TWIKI web page!
ASI has included CHEOPS in its program at the beginning of 2013 (<3 months after selection), with a budget provision till launch. Tavolo negoziale ASI-INAF chiuso ieri (2yr duration). RFI to Industries soon è KOM industrial activity 1 st semester 2014. PROBLEMI??! No Grazie!!!
CHEOPS is another step (a major one) for the Italian exoplanetary community! HARPSN@TNG è GAPS and GTO APACHE, TASTE GAIA SPHERE@VLT ESPRESSO@VLT PLATO ECHO OPPORTUNITÀ??! YES!!!
thanks! THE END! http://www.oact.inaf.it/cheops-it/