PLATO 2.0 (PLAnetary Transits and Oscillations of stars)

Heike Rauer Institute for Planetary Research, DLR, Berlin

and the PLATO 2.0 Team

content

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• Science overview

• Target samples, observing strategy,

data products

• The PLATO 2.0 consortium

organisation

PLATO 2.0

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PLATO 2.0 is a survey mission with the prime goals to:

• detect planets down to Earth size

• characterize the bulk planet parameters

o radius (~2%)

o mass (~10%)

o age (~10%)

• for a large sample of planets

• for orbital distances up to the habitable zone of solar-like stars

• with well-known parameters of host stars

• provide input for improved stellar models and to galactic science

The Method

Techniques Example: Kepler-10 b (V=11.5 mag)

Photometric transit

Asteroseismology

RV – follow-up

Characterize bulk planet parameters Accuracy around solar-like stars for PLATO 2.0:

radius ~2% mass ~10% age known to

~10%

For bright stars: • 4 – ~11 mag for main sample Detection statistics, stellar science: • <16 mag at the faint end

Diversity of „super-Earths“

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Status:

• Large diversity in masses and radii

• Individual planets have large error bars

PLATO error bar

PLATO goal:

Masses: 10%

Radii: 2%

Earth

GJ1214b

Mini gas planets

Low-mass planets have a range of compositions and interior structures for similar masses.

Planet diversity and planet formation

5.5 g/cm3

1.6 g/cm3

<~1 g/cm3

Diversity: future challenges

Super-massive silicate planets?

Super-dense gas planets

inflated gas planets

Planet diversity @ periods >80 days

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All planets Planets with P>80 days

PLATO 2.0 will fill the parameter range for long orbital periods

Our knowledge on planet nature is limited to close-in planets so far.

9 © Petigura/UC Berkeley, Howard/UH-Manoa, Marcy/UC Berkeley

The Goal:

„super-Earths“ in the „habitable zone“

= „super-Earth“

= „super-Earth“

Status: Characterized „super-Earths“ in their habitable zone

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Detected super-Earths • Goal: Detect and

characterize super-Earths in habitable zones

• Status: few

small/light planets in habitable zones detected

„Super-Earths“ with characterized radius and mass

No „super-Earths“ with known mean density in the habitable zone

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Status: Characterized „super-Earths“ in their habitable zone

• Goal: Detect and characterize super-Earths in habitable zones

• Status: few

small/light planets in habitable zones detected

• K-2 (Kepler 2) observe fields in the ecliptic (NASA) plane for ~80 days/field 95 cm aperture, Earth trailing 7 – 17 mag (Koch et al., 2010)

• CHEOPS follow-up, accurate radii (ESA, launch 2017) 30 cm aperture, Earth orbit 6 - 12 mag (CHEOPS Red Book)

• TESS scan the whole sky, ~1 month/field, (NASA, launch 2017) ~2% of sky at poles for 1 year 10 cm aperture, 4 telescopes, Earth-Moon orbit 4 – 13 mag (Ricker et al., 2014)

What’s next?: Space-based

„Super-Earths“ with characterized radius and mass

Prospects: Characterized „super-Earths“ in their habitable zone

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• TESS, CHEOPS, K2 will

mainly cover orbital periods up to ~80 days

• In Solar-System analogues:

No planets characterized outside Mercury‘s orbit without PLATO 2.0!

TESS ecliptic poles

„Super-Earths“ with characterized radius and mass

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Prospects: Characterized „super-Earths“ in their habitable zone

• PLATO 2.0 goal: Detect

and characterize planets up to the habitable zone of solar-like stars.

TESS ecliptic poles

PLATO 2.0 science: Exoplanet AND stellar science

15 © G. Perez Diaz, IAC (MultiMedia Service)

Characterize Exoplanets together with their stars

• Mass + radius mean density (gaseous vs. rocky, composition, structure) • Orbital distance, atmosphere (habitability) • Age (planet and planetary system evolution)

• Stellar mass, radius (derive planet mass, radius) • Stellar type, luminosity, activity (planet insolation) • Stellar age (defines planet age)

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Characterization of exoplanets … needs characterization of stars

Asteroseismology

Example: HD 52265 (CoRoT), a G0V type, planet-hosting star, 4 months data

(Gizon et al. 2013)

Seismic parameters: Radius: 1.34 ± 0.02 Rsun, Mass: 1.27 ± 0.03 Msun, Age: 2.37 ± 0.29 Gyr

CoRoT and Kepler have demonstrated that the required accuracies can be met

with seismic measurement, 2.1 – 2.7 Gyr, Δage/age:13%

no seismic measurement, 0.8 – 5.9 Gyr, Δage/age: 75%

Miglio et al. (2013)

• Gyrochronology of stars via age-rotation relationship:

seismic age versus rotation period from spots • PLATO 2.0 & Gaia:

• seismic + astrometric distances • seismic age-metallicity relations for

giants

Provide accurate ages Calibrate stellar evolution theories Calibrate Galactic age-metallicity

relationship

Probe the structure and the evolution of our Galaxy

Structure and evolution of the galaxy with PLATO 2.0

18 Meibom et al. (2011)

Stellar radiation, wind and magnetic field

Cooling, differentiation

(plate)- tectonics Secondary

atmosphere life

Loss of primary, atmosphere

Formation in proto-planetary disk, migration

Cooling, differentiation

© H. Rauer (DLR)

Planets, planetary systems and their host stars evolve.

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PLATO2.0 science: diversity & planet formation

Determine the planet interior density distribution and constrain the

composition of planets identify potentially habitable terrestrial planets

Transiting terrestrial planets around bright stars for atmosphere follow-up

spectroscopy

Investigate the architecture of planetary systems connection to proto-planetary disk properties evolution with age

characterize host stars incident flux, stellar activity, age, evolution,… Correlate planet and system parameters with age, orbital distances, stellar

type, metallicity, chemical composition

Exoplanet prime parameter characterization

ground based surveys

M dwarf surveys

K2, TESS, CHEOPS PLATO 2.0

hot gas giants YES YES YES YES

hot Neptunes SOME YES YES YES

hot super-Earths maybe YES YES YES

warm gas giants X SOME SOME YES

warm Neptunes X SOME SOME YES

warm super-Earths X

SOME (very cool

dwarfs)

SOME (around M

dwarfs) YES

Image Copyright: Mark A. Garlick. Science Credit: Carole Haswell & Andrew Norton (The Open University)

The PLATO 2.0 mission

PLATO instrument

- 32 « normal » 12cm cameras, cadence 25 s - 2 « fast » 12cm cameras, cadence 2.5 s, 2 colours - dynamical range: 4 ≤ mV ≤ 16

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• Cameras are in groups • Offset to increase FoV

Two designs studied: Multi-telescope approach gives:

- Large FOV (Large number of bright stars)

- Large total collecting area (provides high sensitivity allowing asteroseismology)

PLATO instrument

- 32 « normal » 12cm cameras, cadence 25 s - 2 « fast » 12cm cameras, cadence 2.5 s, 2 colours - dynamical range: 4 ≤ mV ≤ 16

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• Cameras are in groups • Offset to increase FoV

Two designs studied: Multi-telescope approach gives:

- Large FOV (Large number of bright stars)

- Large total collecting area (provides high sensitivity allowing asteroseismology)

Breadboard of one PLATO telescope

Baseline observing strategy 6 years nominal science operation: • 2 long pointings of 2-3 years • step-and-stare phase (2-5 months per pointing)

covers ~50% of the sky

F5/K7

Overview of Stellar Sample Requirements

*: P5 for long AND step&stare phases: ~1.000.000 lightcurves <13mag!

P1: 20 000 stars

P3: 3 000 stars

long pointings

step & stare

P2: 1 000 stars

P4: 5 000 stars 5000 stars V<16 V<15

P5*: 245 000 stars

V<11

V<8

V<15 V<16

V<13

34 ppm

34 ppm

800 ppm

80 ppm

F5/K7

M

F5/K7

mag Noise

in central field

spectral type

50s/600s

50s/600s 50s/50s

600s/- 50s/50s

600s/- 50s/50s

sampling rate

(phot./cent.)

F5/K7

Overview of Stellar Sample Requirements

P1: 20 000 stars

P3: 3 000 stars

long pointings

step & stare

P2: 1 000 stars

P4: 5 000 stars 5000 stars V<16 V<15

P5*: 245 000 stars

V<11

V<8

V<15 V<16

V<13

34 ppm

34 ppm

800 ppm

80 ppm

F5/K7

M

F5/K7

mag Noise

in central field

spectral type

50s/600s

50s/600s 50s/50s

600s/- 50s/50s

600s/- 50s/50s

sampling rate

(phot./cent.)

Exoplanet characterization and asteroseismology

M dwarf host star sample

*: P5 for long AND step&stare phases: ~1.000.000 lightcurves <13mag!

Exoplanet statistics and stellar science

Ground based follow-up

• Radial velocity monitoring needed for planet confirmation and mass determination

• Initial focus on scientificly most

interesting objects

• Legacy to the community

• RV precision needed for an Earth-mass planet can be reached with VLT/ESPRESSO for PLATO 2.0 targets.

Total numbers of characterized planets in core sample

1.0 0.5 0

mas

s (M

Ear

th)

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Separation (a /aHZ)

>300 300 78 30

>800 540 210 70

>1000 265 100 30

Number of characterized planets (Earth to Neptune mass) after detailed model of radial velocity efforts and the impact of stellar activity:

Habitable zone

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Data products • Level 0 (L0) data, which correspond to the data delivered by the individual

telescopes and with some on-board corrections.

• Level 1 ( L1) data, Calibrated photometric lightcurves (and centroid curves) which include further instrumental corrections.

The Majority of L1 data products will become public after calibration • Level 2 (L2) data include

• Planetary transit candidates and their parameters • Asteroseismic mode parameters • Stellar rotation periods and stellar activity models • Seismically-determined stellar masses and ages • List of confirmed and fully characterized planetary systems, combining

information from the planetary transits, the seismology of the planet-host stars, and the follow-up observations.

PLATO 2.0 Mission Consortium

payload data center Science specs

PDC and PSPM • The PLATO Data Center (PDC) and the PLATO Science Preparation

Management (PSPM) are part of the PLATO Ground Segment

• The PDC is in charge of calibrating, validating and analyzing the

PLATO data

• The PSPM developes the scientific methods and tools for data

calibration and analysis, provides specifications for their implementation

into the PDC, and scientifically validates PLATO data

• The PSPM specifies the PLATO input catalogue and organises

preparatory and follow-up observations

Complementary Science

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• Complementary Science (Coordinator Conny Aetrs) – everything to be done with PLATO that is not in the “core” program!

• The core program focusses on getting accurate parameters of exoplanet hosts • The “core” program includes stellar parameters primarily for main sequence stars

(with and without planetary systems) but internal physics of Red Giants is also important in testing models that are applied to main sequence stars (eg internal rotation).

• Complementary Science includes areas such as:

1) Hot star pulsations 2) Red giants as tracers of galactic age 3) CV’s Etc

• Complementary science programmes will will not require re-pointing of the spacecraft or exclusively dedicated observing time.

PLATO 2.0 MILESTONES (Nov 2014) July 2014 – April 2016 Phase B1 March – April 2015 PLATO Payload Development & Consolidation

Review (PDCR) October 2015 Phase B1 data package for I-SRR October – November 2015 Instrument System Requirements Review (I-

SRR) February – March 2016 Spacecraft System Requirements Review

(SRR) May/June 2016 Mission Adoption & SPC approval April 2016 – May 2017 Phase B2 May 2017 – August 2018 Phase C August 2018 – September 2022 Phase D October 2022 – December 2023 Phase E1 (Spacecraft AIT phase) January 2024 Launch M3 January 2024 - March 2030 Phase E2 (Commissioning & Nominal

Operations (6 yrs)) April 2030 - March 2033 Phase F (Post-operations (3 yrs)) April 2033 End of mission

Milestones

Ongoing activities

• ESA Design Requirements and I/F Documents are reviewed

• Payload design consolidated

• Preparation for PDCR

• PDC and PSPM activities starting

• …

• A PLATO Performance Team has formed with people from all elements of

the mission to study instrument and science performance

they may need you: Please provide support with your expertise!

Image Copyright: Mark A. Garlick. Science Credit: Carole Haswell & Andrew Norton (The Open University)

The PLATO 2.0 mission

We need the best possible tools, algorithms, models, catalogues, observational support, … for PLATO!

This requires support from the science

community for PLATO preparation, and for analysis after launch