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Eddington artist impression. ESA Eddington - vital statistics. 3 x 0.9m co-aligned Schmidt telescopes 3 colour filters. 18 x 3Kx2K E2V frame-transfer CCDs 1Mhz (2-8s) readout. FoV=25 sq deg 3 arcsec/pix defocus psf 10-30 arcsec diam.
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ESA Eddington - vital statistics 3 x 0.9m co-aligned Schmidt telescopes 3 colour filters 18 x 3Kx2K E2V frame-transfer CCDs 1Mhz (2-8s) readout FoV=25 sq deg 3 arcsec/pix defocus psf 10-30 arcsec diam Soyuz/Fregat Launch L2 orbit 2008 June 5 (+3?) year mission Eddington UK PPRP Birmingham 10 Oct 2003
Eddington Science Discovery of Small Planets-- hot and habitable Earths (Albedo of hot Jupiter atmospheres) Seismology of Stars-- ages for all major stellar populations thousands of stellar interior maps 1% ages, metalicities. Mixing/rotation 10-20 fields t=1-3 mo Exploration of time domain discovery space Eddington UK PPRP Birmingham 10 Oct 2003
Seismology of Stars • stellar interior maps across the H-R diagram - age-rotation (meridional circulation) - low-mass stars (settling of H, metals) - high-mass stars (convective overshooting, . supernova progenitors, yield to ISM) • 1%ages for Galactic stellar populations • stellar evolution testbed • properties of matter under extreme conditions • Solar chronology in a stellar context Eddington UK PPRP Birmingham 10 Oct 2003
Solar interior rotation Slow surface rotation at poles Shear at base of convection zone Near solid body rotation of core
Pulsating stars span the HR diagram Eddington will allow to study all possible types of pulsating stars Eddington will measure stellar interior structures across the entire HR diagram
Inversion of simulated Eddington data for a 1.45 Msun star Edge of convective core to within 1% Size of convective core determined within 1%!
Accuracy of stellar parameters For an open cluster with moderate mass stars (e.g. Hyades) with 1) classical observables (UBV,parallax, Fe/H, etc) . 2) frequency separations . 3) detailed inversion from observed frequencies Eddington UK PPRP Birmingham 10 Oct 2003
Eddington Exoplanet Science Discover and characterize a large number and variety of extra-solar planets, including “habitable” worlds. Liquid water Rocky, with atmosphere Design to detect habitable planets per star Eddington UK PPRP Birmingham 10 Oct 2003
Design Goal:to detect Earth analogs Transit probability:
Eddington history 2000 - selected as an ESA “Reserve” mission 2002 - fully approved for 2008 launch ESA funds ( 200 Meuro) -- Spacecraft -- Herschel bus “clone” -- Payload (built by industry (Alcatel or Astrium)
Eddington baseline payload • Final definition ongoing! • White light, wide field photometer • Multiple (3x) telescopes • Ca. 0.8 m2 collecting area • Ca. 20 sq. deg field of view
Eddington data products • Long-term, highly accurate photometric light curves of selected targets in the field of view • Up to 100,000 targets in PF field, 20,000 in AS fields • 30 s time resolution in AS fields, 600 s time resolution in PF field • Photon-noise limited
Eddington baseline observing program • 5 yr observational lifetime • 3 yr uninterrupted planet-finding observation • Asteroseismology also performed • 2 yr total asteroseismic observations • 1-3 months duration typical • Planet-finding also performed • Can be interleaved • Both key science goals always ‘on’! • Parallel and auxiliary science always ongoing
Eddington, status • Proposed in early 2000 to ESA as a “flexy-mission” (176 MEur envelope, 192 Meur 2003 value) • Selected as “reserve” mission in late 2000 • Approved in May 2002 as element of ESA’s ‘Cosmic Visions’ science program for launch early 2008 • Currently in a competitive definition phase (“phase B”) with two contractors • Ready to start the implementation phase (“phase C/D”) in May 2004 for a 2008 launch
Eddington development approach • Complete mission is ESA-funded and developed under ESA responsibility • S/C (Herschel bus “clone”) • P/L (Built by industry) • Launch • Ground segment (including SOC) • No dependence on external funding sources
Eddington P/L Consortium • Key scientific role, no H/W procurement • Defines (together with Science Team) and oversees instrument specs and development • Develops flight and ground science S/W • Definition and execution of P/L calibration • Proposal for P/L Consortium received, involves 41 institutions in 11 countries
A community mission • Fully open data policy • No proprietary rights, data immediately available to complete ESA scientific community • Fully open observing program • 1-3 month fields program to be defined by community, through an AO cycle • 3 yr field being currently being defined by Eddington community • Ample space for additional science, additional targets
Eddington low-risk approach • S/C and P/L fully scoped (cost, schedule) by industry • Scientific specs very tight and clear • High level of definition • High technological maturity • No development items, no hidden surprises • As a consequence, no financial risk
3 x 0.9m ~ 2.3 sq.m 20 sq deg 3 colours L2 orbit 1 x 1.2m 100 sq deg white light drift-away orbit Eddington vs Kepler
Kepler, status(from the Kepler web site) • Systems requirements review Oct. 2003 • Preliminary design review Oct. 2004 • Critical design review Aug. 2005 • Launch Oct. 2007 • 60 flight CCDs to be procured (none delivered yet)