Beyond HST: The Universe in High-Definition – UVOIR Space Astronomy in 2030
Julianne Dalcanton & Marc Postman
Science with HST IV Meeting Rome, Italy March 18, 2014 Long History of Large Space UVOIR Telescope Concepts • VLST – 10m-16m concept (ca. 1989) • SUVO – 4m concept (ca. 1998-1999) • Workshop on 10m - 30m VLST (2003) • MUST – 10m concept (ca. 2004-2005) • ATLAST – 8m-16m concepts (ca. 2008-2010) • EUVO – European 8m concept (ca. 2013) • Modular Assembled 20m concept (ca. 2013) Scientifically compelling for over 2 decades! (Average Aperture Diameter – 13.5 meters) “Can we find another planet like Earth orbiting a nearby star? To find such a planet would complete the revolution, started by Copernicus nearly 500 years ago, that displaced the Earth as the center of the universe… The observational challenge is great but armed with new technologies… astronomers are poised to rise to it.”
- U.S. 2010 Astronomy Decadal Review
This is a question whose answer is sought by all of humanity and the search will demand international cooperation. The path has been laid ! for characterizing Earth 2.0 Kepler Hubble Spitzer
CoRoT
Ground-based Coronagraphs Gaia
WFIRST
30-m class telescopes
TESS
JWST PLATO !"#$%&'('$)*+%&'($,)(%&$+-%$%&'('./$ Thick Atmosphere
Methane Oxygen Fraction with terrestrial planets = !Earth FractionWater with detectable biosignature = fBio
OpticalIf : ! Near-Infrared $ f ~ 1 then D ~ 4m Earth Bio0'12'($('#-2%#$ 8-meterTel 16-meter The signature of life is encoded inf the < 1 then D 8m spectrum! Earthof the Earth$ Bio $ tel ~
70 !Earth $ fBio << 1 then DTel ~ 16m a > 12 Earths $ 60
50
40
30 # 4 Earths 20 4-meter 10 of total integration time of total integration time
0 Above: Distribution of all FGK stars within 45 pc of the Sun Number of Exo-Earths in 1 year 2-m 4-m 8-m 16-m where a R=70 spectrum of an Earth-twin could be acquired Telescope Size in <500 ksec shown as a function of telescope aperture. Assumes eta_Earth = 0.1 and IWA = 2"/D. R=500 Spectrum of 1 Earth-mass Terrestrial Exoplanet at 10 pc Exposure: 503 ksec on 8-m Reflectance ! (Planet Mass)2/3 Bkgd: 3 zodi 56 ksec on 16-m 5 Earth-mass: 172 ksec on 8-m Contrast: 10-10
SNR=10 @ 760 nm
H2O
H2O H2O H2O
O2(")
O2(B) H2O
H2O
O2(A)
O2(A) Detail:
@ 750 nm
We don’t expect all habitable worlds to have spectra like this but interpreting their spectra will require this kind of instrumental capability. 3'%'45*6$37-(*)2$8&+%+9'%(74$:)(7);727%<$7*$ ,=+12)*'%#$$$ Ford et al. 2003: Model of broadband photometric temporal variability of Earth
0.09 Earth at 10 pc
0.08 16-m 8-m 4-meter Earth at 20 pc 0.07 ~9 days
Reflectivity 16-m 8-meter 4-meter 0.06
0.05 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 Time (days) Require S/N ~ 20 (5% photometry) to detect ~20% temporal variations in reflectivity. Reconstruction of Earth’s land-sea ratio from disk-averaged time-resolved imaging with the EPOXI mission.
Developing a Shared Vision
Exoplanets Everything Else
In the UVOIR, the goals and requirements are very similar. Developing a Shared Vision
Exoplanets Both Everything Else
•!Large aperture •!Diffraction limited •!Optical & NIR • Coronagraph or ! • UV capabilities starshade ! • Broad instrument • Superb mirror ! ! suite stability Developing a Shared Vision
Exoplanets Everything Else +
One mission + Broad science = Large Community Emerging science themes
• Exoplanets • “The Universe in High-Definition”
HDST: High-Definition Space Telescope 24x pixel density
SDTV UltraHD 720x480 3820x2160
24x image sharpness
HST HDST 2.4 meter 12 meter HDST: Breaking Resolution Barriers Redshift 0.1 0.3 1 2 3
HST JWST 100 pc everywhere! HDST8 HDST16 10 pc @ 100 Mpc
1 pc @ 10 Mpc
0.1 pc @ 1 Mpc
LMC M31 M87/Virgo Coma Bullet Cluster Size scales
1 pc
5 pc
~200 pc HDST: Resolving 100 pc star forming regions everywhere in the universe! 1 pc resolved out to 10-25 Mpc.
ALMA: molecular gas on ~0.1-0.5” scales JWST: Heavily enshrouded stars HDST: Emerging stars HDST: Breaking Resolution Barriers Redshift 0.1 0.3 1 2 3 HST JWST HDST8 HDST16
Orion Bulge LMC M31 M87/Virgo Coma Bullet Cluster General Astrophysics Drivers
• Large aperture: Throughput + Resolu on • UV (90 nm) through NIR (>2.5 mm, non-cryo)
- Issues: Coa ngs, Compa bility w/ Coronagraphy
• Large FOV + Spectroscopic Mul plexing
- Issues: Tradeoff between cost of more complex instruments vs. efficiency gains The Case for UV Multiplexing A true multi-object / IFU capability in the UV would trigger a revolution in our ability to dissect gas flows, and the stellar populations that give rise to them, with dense sampling of spatial variations and all relevant physical variables.
Also would permit detailed mapping of Would also support intensive UV continuum and line SFR metrics, spectroscopy of every spatially resolved, from z = 0 to z ~ 1. Magellanic Cloud OB star. Dissecting Halo Gas w/ Background QSO Simulations from Shen et al. 2012
metal-rich outflow
metal-poor infall
HI column 900 - 1150 Å densities & OVI Slide credit: J. Tumlinson “Parallel” Astrophysics During Long Exoplanet Spectroscopic Observa ons • Es mated median single-visit exposure me for obtaining an exoplanet spectrum is ~100 ksec. • Will allow parallel deep imaging of nearby fields to 10-sigma limi ng depths of 33 AB mag in UV, visible and 32 AB mag in NIR.
19 Considerations:
• Need big leap in aperture (compared to HST) • Guaranteed discovery space, even with long launch me. • Highly synergis c with many upcoming facili es
- TESS, JWST, EUCLID, WFIRST, PLATO, ATHENA+ - 20-40m ground-based telescopes, LSST - ALMA, SKA How do we get there?
U.S. Activities: • ATLAST NASA Center (GSFC/JPL/MSFC) Study • AURA “Beyond JWST” Commi ee • NASA “EXOPAG” & “COPAG” working groups • Coronagraph & Starshade developments for WFIRST and Exoplanet Probe concepts
Goal: Mature technology and mission concepts in preparation for 2020 Decadal Technology and Innovation Enable HDST science Lightweight Mirrors!
~3x 16x
30x
Gemini Mirror!
How much would an 8-m mirror weigh?!
Gemini HST JWST AMT
20,000 kg 7,000 kg 1,250 kg 650 kg HST Mirror!
JWST Mirrors! AMT Prototypes! Technology Changes the Cost Curve
0.01" 1" Credit: E. Elliot JWST ) -1 /kg) /kg) 2
0.001" 0.1" (m
(m Spitzer
HST Collecting Area per Launch Mass Area per Launch Mass Collecting Collecting Area per Launch Volume Area per Launch Volume Collecting
0.0001" 0.01" 1990" 2000" 2010" 2020" Year of Launch
(If we had JWST mirror technology in 1980, cost of HST would have been 8x lower) Related Key Technologies Starshade concepts are being studied Non-cryogenic by NASA. Optical model has Optics! been tested on ground – confirms diffraction theory upon which Dual foci: design is based. •! Cass for UV and Exoplanets •! TMA for wider field instruments
Active Wavefront Sensing & Control 1e-8 Systems 1e-9 •! Heritage from ground, WFIRST, 1e-10 JWST heritage mirror and other industry/ deployment design, compatible with High Performance Coronagraphs being govt. applications existing and near- studied, one will fly on WFIRST future launch vehicles. !"#$%&'()*+',$)*,-$%,$)*#.'#$/0)
HST ! The people’s telescope! ! Hubble 2.0! JWST!segmented optics in space! ! WFIRST/AFTA!active mirror control! giga-pixel array! robotic servicing! Test HP Coronagraph!
HDST: Hubble 3.0! Tests light-weight segmented optics! light-weight segmented optics! active optics control! fully active optics control! human-operated robotic assembly! tele-robotic servicing! giga-pixel array! ISS! Ultra-high contrast imaging ! commercial crew & SLS, and other heavy lift launch vehicles! TESS!
Finding potentially habitable exoplanets that can be characterized by HDST! ! PLATO! ESA L4 Selection
2015! 2020! 2025! 2030! 2035! Decadal Review in U.S. For this to Succeed, do… • Have a killer app with full community support. • Develop mission that is a must-do scientifically and that cannot be done any other way. • Ensure project is highly-ranked by community reviews. • Identify & highlight complementarity with other facilities. • Still like the science and the project 10 – 20 years from now. • Offer project science and grant support to the whole community. • Keep selling the project to the community until launch
Slide credit: Rogier Windhorst For this to Succeed, don’t…
• Have community in-fighting • Have other projects canceled because of this one, or perception thereof. • Have science and grant support for a selected few. • Ignore community input on project science priorities. • Ignore importance of great communication with patrons: scientists, contractors, tax-payers, politicians • Ignore importance of great communication with international partners.
Slide credit: Rogier Windhorst Where We Are • UVOIR access from space is fundamental to understanding the universe and the life within it. • “Game Changing” science requires substantial increase in aperture. • Enabling such a capability requires alliances, so the exoplanet and astrophysics communities need to work together to make their next generation large UVOIR space telescope the SAME mission. • NASA can lead such a mission but the mission will require significant international partnerships. • Need your inputs on science cases, ideas for advancing technologies, science instruments concepts and strategies for international collaboration. Giving input or Further Ques ons
• This mee ng • h p://www.aura-astronomy.org/hdst • Talk to any commi ee member, at any me • White papers always welcome
Goal is to develop the most compelling mission that also serves the largest possible community. All input is welcome! Back Up Slides
30 31 32 8+##7;2'$@U[$R+4)2$82)*'$[22+4)5+*$
17 arc min
Guider Guider 4 x 4 arcmin Vis/NIR 4 x 4 arcmin Wide Field Imager (may use Dichroic for 2 channels) Multi-Object
8 arc min Integral Field Spectragraph Guider Unit (IFU) 8 x 8 arc min (MOS) Guider 4 x 4 Array 4 x 4 arcmin arcmin up to 4 x 4 arc min 4 x 4 arc min
25 arc min
WFOV Total Available Focal Plane
WFOV Science Focal Plane
From Lloyd Purves, GSFC!