The Occurrence of Planets
And Intelligent and
Life in the Universe
Mass-Radius Relation
from Kepler
Keck
Tel Aviv
7 December 2012
Geoff Marcy
University of California
Thanks to:
Shay Zucker
Amiel Sternberg
The Occurrence of Planets
And Intelligent and
Life in the Universe
Mass-Radius Relation
from Kepler
Keck
Tel Aviv
7 December 2012
Tsevi Mazeh
Thanks to:
Shay Zucker
Amiel Sternberg
Acknowledgements
William Borucki
David Koch
Stephen Bryson
Jason Rowe
Roger Hunter
Marcie Smith
Susan Thompson
Bruce Clark
Rob Lewis
Guillermo Torres
Francois Fressin
Jean-Michel Désert
Lars Buchhave
Sam Quinn
Dan Fabrycky
Debra Fischer
Dimitar Sasselov
Kepler’s Heavy Lifters
Natalie Batalha
Thomas Gautier
Steve Howell
Charlie Sobeck
Tsevi Mazeh
David Latham
Fergal Mullally
Joe Twicken
Elisa Quintana
Ron Gilliland
Eric Ford
Elliott Horsch
Tom Barclay
Jessie Christiansen
Jack Lissauer
Jon Jenkins
Mike Haas
Doug Caldwell
Jeff Kolodziejcak
Martin Still
Shawn Seader
Jie Li
David Charbonneau
David Ciardi
Chris Burke
Leslie Rogers
Martin Still
Martin Stumpe
Peter Tenebaum
Lucianne Walkowicz
Bill Cochran
Mike Endl
Acknowledgements
William Borucki
David Koch
Stephen Bryson
Jason Rowe
Roger Hunter
Marcie Smith
Susan Thompson
Bruce Clark
Rob Lewis
Guillermo Torres
Francois Fressin
Jean-Michel Désert
Lars Buchhave
Sam Quinn
Dan Fabrycky
Debra Fischer
Dimitar Sasselov
Kepler’s Heavy Lifters
Natalie Batalha
Thomas Gautier
Steve Howell
Charlie Sobeck
Tsevi Mazeh
David Latham
Fergal Mullally
Joe Twicken
Elisa Quintana
Ron Gilliland
Eric Ford
Elliott Horsch
Tom Barclay
Jessie Christiansen
Jack Lissauer
Special Thanks:
Jon Jenkins
Mike Haas
Doug Caldwell
Jeff Kolodziejcak
Martin Still
Shawn Seader
Jie Li
David Charbonneau
David Ciardi
Chris Burke
Leslie Rogers
Martin Still
Martin Stumpe
Peter Tenebaum
Lucianne Walkowicz
Bill Cochran
Mike Endl
Andrew Howard, Lauren Weiss, Howard Isaacson, Jason Rowe, John Johnson
2300 Small Exoplanets
Size Relative to Earth
Jupiter-size
Neptune-size
Earth-size
Orbital Period in days
5
Size Relative to Earth
2300 Small Exoplanets
Jupiter-size
Neptune-size
Earth-Size
Close-in
Orbital Period in days
6
Earth-size
Kepler: Hundreds of Earth-size Planets
– in Tight Orbits
P = 6.098 days
0.87 R +
Multiple Transits yield
sufficient S/N Ratio for
detection.
P = 19.577 days
1.03 R+
Data binning yields
obvious transit signatures
Francois Fressin et al. 2012
Size Relative to Earth
2300 Small Exoplanets
Jupiter-size
Neptune-size
R=1-4 REarth
- Not in S.S.
- Interior: Rock + ?
- Formation ?
Orbital Period in days
8
Earth-size
Define Planet Occurrence
For each RPL and Period:
Define Planet Occurrence
For each RPL and Period:
Define the Stellar Domain:
Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence
Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
Define the Survey Domain:
Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence
Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
Note:
Only 59,000 Kepler Target
stars meet these stellar criteria
Define the Survey Domain:
Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence
Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
Note:
Only 59,000 Kepler Target
stars meet these stellar criteria
SNR Threshold of Transit: 10
Demand SNR > 10 in Quarter 3
Define the Survey Domain:
Stellar Parameters and SNR of Transit
Stellar Domain: FGK Main Sequence
Teff = 4100 – 6100 K
log g = 4.0 – 4.9
Kepmag < 15 mag
Note:
Only 59,000 Kepler Target
stars meet these stellar criteria
SNR Threshold of Transit: 10
Demand SNR > 10 in Quarter 3
SNR Depends on
• planet radius
• # of transits
• Photometric noise
Number of Target Stars Capable of Achieving
SNR > 10 in Quarter 3
Target Star Parameters: Teff=4100-6100 K, log g=4.0-4.9, Kepmag<15
mag
15
Howard, Marcy, Kepler Team. (2011)
Define Planet Occurrence
For each RPL and Period:
17
Howard, Marcy, Kepler Team (2011)
18
Howard, Marcy, Kepler Team (2011)
19
Howard, Marcy, Kepler Team (2011)
20
Howard, Marcy, Kepler Team (2011)
Focus on a single domain
In Period and Radius
21
Howard, Marcy, Kepler Team (2011)
Naïve:
Count the planets in this domain.
Focus on a single domain
In Period and Radius
22
Howard, Marcy, Kepler Team (2011)
Naïve:
Count the planets in this domain.
Best:
Augment each planet by its
# of “inclined” twins: a/RSTAR .
Focus on a single domain
In Period and Radius
23
Howard, Marcy, Kepler Team (2011)
Augment Each Transiting Planet by the
# of (undetected) Inclined Twins
a
RSTAR
# Planets at All Inclinations = a / RSTAR
Naïve:
Count the planets in this domain.
Best:
Augment each planet by
# of “inclined” twins: a/RSTAR:
Focus on a single domain
In Period and Radius
25
Howard, Marcy, Kepler Team (2011)
Naïve:
Count the planets in this domain.
Best:
Augment each planet by
# of “inclined” twins: a/RSTAR:
Typically 5-20.
Focus on a single domain
In Period and Radius
26
Howard, Marcy, Kepler Team (2011)
Define Planet Occurrence
within each cell:
Distribution of Planet Radii
For Orbital Periods < 50 Days
10%
of stars
8%
of Ghave
stars
Planets
REarthof
.
have2.0-2.8
a planet
2.0-2.8 REarth
1% of stars have
Planets 8-11 REarth.
Howard, Marcy, Kepler Team, as of Sept. 2011
Howard et al. Analysis:
Redone
with Planet Candidates
through Quarter 6
from Batalha et al. 2012
Distribution of Planet Sizes
Is Decline
to 1 REarth
Real ?
Petigura, Howard, Marcy, Kepler Team - Nov 2012
2300 Small Exoplanets
Size Relative to Earth
Batalha et al. 2012
Jupiter-size
Neptune-size
Earth-Size:
Not many…
Orbital Period in days
31
Earth-size
Distribution of Planet Sizes
Is Decline
to 1 REarth
Real ?
Or is it due to
Incompleteness in
The Kepler pipeline?
SNR (SES) ~ 1 for R=1 REarth
Petigura, Howard, Marcy, Kepler Team - Nov 2012
New Kepler Pipeline
by Erik Petigura
• New CBVs
•
New Search
Algorithm
Petigura’s Kepler Pipline
Adopted CDPP Threshold:
“Best 12,000 Kepler Stars”
Best 12000
Planets Detected
in “Best 12000” Kepler Stars
Petigura et al. 2013
Now:
- Assess completeness
- Compute occurrence
ala Howard et al.
Completeness Measurement
Inject Mock Transits
into Actual Kepler
Raw photometery
Detection Completeness:
> 80%
- Radius = 1.2 – 4 REarth
- Period > 50 d
Petigura et al. 2013
Planets Detected
in “Best 12000” Kepler Stars
Petigura et al. 2013
Now make
Same corrections
As in Howard et al.
Fressin et al. Occurrence
Occurrence is
Flat Shortward
of 2 REarth
Agreement with
Petigura & Howard
Mass-Radius
Diagram
Planet
Mass-Radius
Diagram
104
20c
246
321
39
20b
Kepler Planet Masses and Radii
KOI-94
KOI-94 Photometry:
4 Transiting Planets
P=3.74 d
R=1.7 RE
P=10.42 d
R=4.3 RE
P=22.34 d
R=11.3 RE
P=54.32 d
R=6.56 RE
Lauren Weiss et al. 2013
Doppler Measurements of KOI-94:
Masses for two planets.
Only Upper limits for two.
Lauren Weiss et al. 2013
135 Exoplanets with Mass and Radius
Planet Radius vs Mass
•Two
mass domains:
MCRIT = 150 MEARTH
• Affect
of stellar Flux
on Planet:
•M>150 MEARTH: Bloated
•M<150 MEARTH: Smaller
Weiss, Marcy, et al. 2013
Planet
PlanetRadius
Radiusvs
vsMass
Mass
Weiss, Marcy, et al. 2013
Planet
PlanetRadius
Radiusvs
vsMass
Mass
Constant Density:
R ~ M1/3
Radius rises faster
than solid interior!
Implication:
Admixture of
more volatiles with
Increasing mass.
i.e. Water or H + He.
Planet
PlanetRadius
Radiusvs
vsMass
Mass
Planet
PlanetRadius
Radiusvs
vsMass
Mass
Electron Degeneracy:
R ~ M-1/3
Radii rises faster
Than e- degeneracy.
Implication:
Admixture of
more volatiles with
Increasing mass.
i.e. Water or H + He.
Planet Density vs Mass
Planet Density vs Mass
Models:
Mordasini et al.
Chiang & Laughlin:
Rock + Gas
2300 Small Exoplanets
Up next: Habitable Zone Earths
Size Relative to Earth
Jupiter-size
Neptune-size
Earth-size
Extended mission
domain
Orbital Period in days
53
Earth
analogs
Summary
• Planet R(M,Flux) becoming defined.
• Two Domains: Critical Mass at 150 MEarth
• Radii increase faster with Mass than Expected::
Amt. of Volatiles increases with mass.
•
Planet Occurrence:
Rises from 20-2 REarth
Flat from 2.0–1.2 REarth
•
Questions:
-Interiors 2-4 REarth and 1-2 REarth
-Occurrence of Planets from 2 – 0.5 REarth