The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super...
Transcript of The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super...
![Page 1: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/1.jpg)
THE
MISSIONAndrea Fortier
on behalf of the CHEOPS Team Centre for Space and Habitability, University of Bern, Switzerland
Latin American Symposium on Small Satellites: Advanced Technologies and Distributed Systems 07. March 2017, Buenos Aires, Argentina
![Page 2: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/2.jpg)
![Page 3: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/3.jpg)
Overview
• Introduction to extrasolar planets • Mission Motivation, Objectives & Science Goals • CHEOPS Design • Mission status • Expected Performances • Summary
![Page 4: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/4.jpg)
Introduction to extrasolar planets
• As of 6th March 2017, a total of 3,586 exoplanets in 2691 planetary systems (603 multiple planet systems) are listed in the Extrasolar Planets Encyclopaedia.
• The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, by M. Mayor & D. Queloz (U. of Geneva) when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi. 51 Peg is a very bright, Sun-like star. 51 Peg b has a minimum mass about half of the mass of Jupiter.
![Page 5: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/5.jpg)
What are exoplanets made of?
Introduction to extrasolar planets
![Page 6: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/6.jpg)
What are exoplanets made of?
Introduction to extrasolar planets
gas giantsNeptune-like
planets
Earth-like planets
![Page 7: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/7.jpg)
Why CHEOPS?
The transit technique
➨ radius of the planet
![Page 8: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/8.jpg)
The radial velocity technique
➨ Mp sin(i)
Why CHEOPS?
The transit technique
➨ radius of the planet
Mp & Rp ➨ ρp
![Page 9: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/9.jpg)
The CHEOPS mission
![Page 10: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/10.jpg)
Milestone Timecall issued March, 2012
proposal due June, 2012
mission selection October, 2012
mission adoption February, 2014
launch End 2018
Nominal lifetime 3.5 years
ESA small mission requirements
• Science: top rated science in any area of space science
• Cost: cost to ESA not to exceed 50 M€ • Schedule: developed and launched within 4
years
![Page 11: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/11.jpg)
Consortium MembersA mission of many challenges Small mission, large organisation!
![Page 12: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/12.jpg)
SwitzerlandMission lead
Instrument lead Science operations centre
A mission of many challenges Small mission, large organisation!
PI: Willy Benz, U. Bern
![Page 13: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/13.jpg)
C H E O P S Mission Consortium
GermanyFocal plane assembly & sensor electronics
ItalyTelescope
AustriaDigital processing unit, power converter & flight software
HungaryRadiators
BelgiumBaffle and Cover
SwitzerlandMission lead
Instrument lead Science operations centre Instrument
PI: Willy Benz, U. Bern
![Page 14: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/14.jpg)
C H E O P S Mission Consortium
SwedenData flow simulator
UKQuick look
FranceData reduction pipeline
PortugalMission planning, archive, & data reduction pipeline
SpainMission operations centre
GermanyFocal plane assembly & sensor electronics
ItalyTelescope
AustriaDigital processing unit, power converter & flight software
HungaryRadiators
BelgiumBaffle and Cover
SwitzerlandMission lead
Instrument lead Science operations centre InstrumentGround Segment
![Page 15: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/15.jpg)
Detect the transit of known super-Earths
Ground-based RV surveys HARPS, HARPS-N, HIRES, SOPHIE (ongoing) CARMENES, SPIRou, ESPRESSO (incoming)
Measure accurate light curves for Neptunes
Ground-based transit surveys NGTS (on going)
TESS (2017)
K2
20% open time (3.5-yr mission)
Observation strategy: Follow-up
![Page 16: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/16.jpg)
What CHEOPS will do:➡ Perform 1st-step characterisation of super-earths & neptunes by measuring accurate radii & bulk densities for such planets orbiting bright stars
➡ Provide golden targets for future atmospheric characterisation by finding the planets most amenable to deep atmospheric studies
How CHEOPS will do it:➡ High-precision photometry (~ 20 ppm precision for bright stars)➡ Observing stars almost anywhere on the sky
CHEOPS science case
![Page 17: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/17.jpg)
700 km
CHEOPS orbit
Sun
120°
OBS
ERVA
TIO
NS 35°
1 April
21 December
21 June
10 September
Orbit
Low (700 km) Earth Sun-synchronous orbit LTAN 6 am
![Page 18: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/18.jpg)
✦ Earth occultation & stray light exclusion angle
✦ Sun exclusion angle
✦Moon exclusion angle
✦South Atlantic Anomaly
Low Earth(650-800 km) Sun-synchronous orbit LTAN 6 am
Observability constraints
![Page 19: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/19.jpg)
Sky visibility
![Page 20: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/20.jpg)
What is special about CHEOPS ?
CHEOPS is complementary to all other transit missions
CHEOPS is a photometric observatory looking at one object at a time
• it will measure highly accurate signals- 20 ppm accuracy over 6 hours for G-type stars with mV < 9
“super Earth”- 85 ppm accuracy over 3 hours for K-type stars with mV < 12
“Neptune characterisation"• it can point at any location over more than 50% of the sky
- can choose the best targets for transit search- can improve radius measurements- can confirm transiting planets on larger orbits- can search for additional planets
![Page 21: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/21.jpg)
Design
CHEOPS design
![Page 22: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/22.jpg)
Incident FluxIncident Flux
CHEOPS telescope
![Page 23: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/23.jpg)
30 cm effective aperture optical bandpass 330-1100 nm, on-axis
carbon-fibre structure defocused PSF
payload mass 60 kg
![Page 24: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/24.jpg)
CHEOPS: Spacecraft Accommodation
Primary structureSolar array
Fixed sunshield
Star Trackers Optical Heads
Secondary Structure
S/C contractor: ECE-CASA Total satellite weight: 280 kg
Total cost: ~ 110 M€
Telemetry: 1.2 Gbit/day (S-band) On-board data stacking
Measurement cadence: 1 min-1
![Page 25: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/25.jpg)
Focal Plane
Frame-transfer CCD, e2v CCD47-20, AIMO
plate scale: 1 arcsec = 1 pixel
Stabilized @ -40 C to 10 mK
![Page 26: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/26.jpg)
Observation principle
Frame-transfer CCD
![Page 27: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/27.jpg)
1k×1k
Observation principle
200x200 subarray on-board stacking cadence 20–60 s-1
![Page 28: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/28.jpg)
Observation principleCHEOPSim
![Page 29: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/29.jpg)
Observation principle
24 pixels (24”)
•Jitter mitigation: • Pointing stability: jitter < 4” rms • PSF is purposely defocused • Pixel-to-pixel FF precision <0.1%
• Thermal stability: • Rotating field
• Triangular shape of the PSF
![Page 30: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/30.jpg)
CHEOPS: Science Data
Exposure time per frame: 0.1 sec - 60 sec [0 sec - 10 min]Data download: on board co-addition (1 image per minute)
![Page 31: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/31.jpg)
Mission status
![Page 32: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/32.jpg)
Environmental tests
T/V chamber @U. Bern
![Page 33: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/33.jpg)
Vibration tests
Shaking telescope @U. Bern
Shaking satellite @RUAG, Zurich
![Page 34: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/34.jpg)
THE critical test!
@CASA, Madrid
![Page 35: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/35.jpg)
CHEOPS performance
![Page 36: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/36.jpg)
Performances
• Noises are estimated based on a mixture of • measurements
(e.g. RON, QE variability, pixel-to-pixel sensitivity) and • simulations
(jitter over CCD, shot noise, cosmic rays) • Predicted noise performance is calculated for three
reference cases:
Target Time-scale Name Predicted Noise
A G2 mag 6 6h “super Earth”: bright end 16.0 ppm < 20 ppm
B G2 mag 9 6h “super Earth”: faint end 18.6 ppm < 20ppm
C K2 mag 12 3h “Neptune characterisation” 79.5 ppm < 85 ppm
![Page 37: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/37.jpg)
Summary
CHEOPS in the web: http://cheops.unibe.ch/ http://sci.esa.int/cosmic-vision/49469-cheops/
• CHEOPS is Europe’s next exoplanet mission (2018)
• CHEOPS is a follow-up machine, Knowing when to look at a star makes CHEOPS extremely efficient➡ Provides a first-step characterisation of low-mass exoplanets➡ Collects the golden targets for future in-depth characterisation ➡ Allows 20% open time for high-precision photometry science
![Page 38: The CHEOPS Mission @ BA2017 · -20 ppm accuracy over 6 hours for G-type stars with m V < 9 “super Earth”-85 ppm accuracy over 3 hours for K-type stars with m V < 12 “Neptune](https://reader033.fdocuments.in/reader033/viewer/2022060409/5f10192e7e708231d4476ffe/html5/thumbnails/38.jpg)
CHEOPS Workshop + Open Time ConferenceSchloss Seggau / 24 – 28 July 2017
http://geco.oeaw.ac.at/links_CHEOPSsw17.html
Thank you!