hubble science briefing
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Dan Coe - STScI 1Jan 24, 2013
Hubble Science Briefing
CLASHCluster Lensing And Supernova survey with Hubble
Hubble Uses Gravitational Lensing to Discover Most Distant Galaxies
Dan CoeSpace Telescope Science Institute
Dan Coe - STScI 2
Hubble is now observing galaxies97% of the way back to the Big Bang,
during the first 500 million years
Jan 24, 2013
Dan Coe - STScI 3
Previous searches for galaxies in the first 500 Myr came up short.Only one candidate was found where six were expected.
This suggested a dramatic buildup in galaxy numbers.
Jan 24, 2013
adapted from Bouwens12see also Oesch12
BIG BANGtimeTODAY (13.7)
Dan Coe - STScI 4Jan 24, 2013
adapted from Bouwens12see also Oesch12
TODAY (13.7) BIG BANGtime
(log
suns
/ ye
ar /
cubi
c m
egap
arse
c)
(billions .of years)
galaxies build upthen
run out
of gas
Previous searches for galaxies in the first 500 Myr came up short.Only one candidate was found where six were expected.
This suggested a dramatic buildup in galaxy numbers.
Dan Coe - STScI 5
Such dramatic evolution could havesurprising implications
• Did galaxies only just start forming then?(Unlikely based on stellar masses observed later)
Jan 24, 2013
Dan Coe - STScI 6
Such dramatic evolution could havesurprising implications
• Not enough faint galaxies to reionize the universe (stripping electrons from atoms)?
Jan 24, 2013
Robertson10
time
May require a more exotic energy source such as dark matter self-annihilation
+
-
+
-
+
-
Atoms, theycome together
Atoms, theyfall apart
We are allmade of stars
– paraphrasing song lyrics by Moby
Reionization
-
Dan Coe - STScI 7
Two complementary programs have now identified five candidate galaxies
in the first 500 million years
• UDF Ultra Deep Field (now even deeper!)
• “CLASH” – using gravitational lensing from “cosmic telescopes” to magnify the distant universe
Jan 24, 2013
Dan Coe - STScI 8
The Hubble Space Telescope,now in its 23rd year of operation,
is more powerful and advanced than ever
Servicing Mission 4 (2009)
Jan 24, 2013
May 2009
Improved imaging at near-ultraviolet and near-infrared wavelengths
The Wide Field Camera 3 (WFC3) was installed during Servicing Mission 4 (center white panel)
Dan Coe - STScI 9
Hubble now has four operational imagers / spectrographs
• Two primary cameras:– Advanced Camera for Surveys (ACS)– Wide Field Camera 3 (WFC3)
• Two spectrographs:– Space Telescope Imaging
Spectrograph (STIS)– Cosmic Origins Spectrograph (COS)
Jan 24, 2013
J. HechtLaserFocusWorld
Dan Coe - STScI 10
Hubble Multi-Cycle Treasury Program
• To help realize Hubble’s full potential• First ever call for multi-year proposals• 39 programs were proposed, 3 were approved
– Combined 5 months of Hubble observing time, carried out over 3 years: Fall 2010 – Fall 2013
– PHAT: stars– CANDELS: galaxies– CLASH: galaxy clusters
Jan 24, 2013
Dan Coe - STScI 11Jan 24, 2013
PHATPanchromatic Hubble Andromeda Treasury Survey
PI: Julianne Dalcanton
stars
region being observed with Hubble
Dan Coe - STScI 12Jan 24, 2013
PHATPanchromatic Hubble Andromeda Treasury Survey
PI: Julianne Dalcanton
PHAT progress as of Nov 2012;Hubble will image 414 contiguous fields upon completion
stars
Dan Coe - STScI 13
CANDELSCosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
PIs: Sandra Faber & Harry Ferguson
Jan 24, 2013
galaxies
Dan Coe - STScI 14
CLASHCluster Lensing And Supernova survey with Hubble
PI: Marc Postman
Jan 24, 2013
galaxyclusters
Dan Coe - STScI 15
CLASHCluster Lensing And Supernova survey with Hubble
PI: Marc Postman
Two primary goals of CLASH are to use gravitational lensing to:
– Reveal dark matter, the “scaffolding” of structure formation
– Magnify galaxies in the distant universe
Jan 24, 2013
galaxyclustersObserving 25 galaxy clusters including MACS0416-24 (background)
Dan Coe - STScI 16
Gravitational lensing in action
Jan 24, 2013
Animation: http://www.spacetelescope.org/videos/heic1106a/ – NASA, ESA & L. Calçada
Dan Coe - STScI 17
Gravitational lensing in action
Jan 24, 2013
Animation: http://www.spacetelescope.org/videos/heic1106a/ – NASA, ESA & L. Calçada
Light follows the curved space to uslike golf balls along
a putting green
Cluster mass bends space according to Einstein’s
Relativity
Dan Coe - STScI 18Jan 24, 2013
Strong gravitational lensing producesmultiple magnified images of distant galaxies
Abell 383 – NASA, ESA, J. Richard, J. P. Kneib; M. Postman
distant galaxy observed when the universe was 900 million years old
Dan Coe - STScI 19Jan 24, 2013
Gravitational Lensing
Dan Coe - STScI 20Jan 24, 2013
Wine Glass Lensing
Phil Marshall
Dan Coe - STScI 21Jan 24, 2013
Abell 1689 – D. Coe
Most of the mass is dark matter
Dan Coe - STScI 22Jan 24, 2013
Most of the mass is dark matteras revealed by gravitational lensing
Abell 1689 – D. Coe
Dan Coe - STScI 23Jan 24, 2013
DarkMatter
23%
DarkEnergy
72% Known 5%
Stars 2%
Neutrinos 1%
Heavy Elements 0.1%
Gas15%
DarkMatter
82%
MatterEverything
Dark matter makes up most of the stuff in the universe
Dan Coe - STScI 24Jan 24, 2013
Dark Matter FAQ (Frequently Asked Questions)
Is that like black holes?Black holes make up some of the dark matter,
but not much
Is Pluto a planet?Sorry, not anymore.
Yes, we are redoing all the horoscopes.
Dark matter may be made of particles we’ve yet to discover
Dan Coe - STScI 25Jan 24, 2013
Dark Matter FAQ (Frequently Asked Questions)
Is that like black holes?Black holes make up some of the dark matter,
but not much
Is Pluto a planet?Sorry, not anymore.
And yes, we are redoing all the horoscopes.*
Dark matter may simply be made of particles we’ve yet to discover (the “next Higgs”)
*We don’t actually do the horoscopes
Dan Coe - STScI 26Jan 24, 2013
Zolt LevayMACS 1206-08
Dan Coe - STScI 27Jan 24, 2013
Zolt LevayMACS 1206-08
A river runs through it
Dan Coe - STScI 28Jan 24, 2013
Zolt LevayMACS 1206-08
A river runs through it
Dan Coe - STScI 29Jan 24, 2013
Zolt LevayMACS 0647+70
Dan Coe - STScI 30Jan 24, 2013
Zolt LevayMACS 0647+70
Multiple images of strongly lensed
galaxiesAdi Zitrin
Dan Coe - STScI 31
Three strongly lensed images of MACS0647-JD:a candidate for the most distant galaxy yet known
Jan 24, 2013
may have highest “redshift”yet observedz ≈ 11
Dan Coe - STScI 32Jan 24, 2013
Galaxy redshifts are primarily due toexpansion of space, not Doppler shift
Earthdistant galaxy
Emitted blue light…
Expanding universestretches lightto longer wavelengths …stretched to green…
…then red (or even infrared) when observedESO animation: http://www.eso.org/public/videos/redshiftv/
Redshift (z) =stretch factorminus one
time
Dan Coe - STScI 33
Wavelength
Observed Lyman break reveals redshiftof a distant galaxy
Jan 24, 2013
ObservedFlux
0.1216(1+z) μm
+
-
redshifted Lyman break
These energetic photonsget absorbed as theyionize / excite atoms
redshifted galaxy light
Ultraviolet light with wavelengths lower than
Lyman-alpha (0.1216 μm) never reaches us
Lyman-alpha forest /Gunn-Peterson trough
Dan Coe - STScI 34
MACS0647-JD appears to be at redshift 11,its light traveling 13.3 billion years to reach us.
During that time, the universe has expanded in size by a factor of 12,redshifting the Lyman break from 0.1216μm to 1.46μm.
Jan 24, 2013
Visible light Infrared lightUltraviolet light
Hubble filters J-bandunprecedented number of
Dan Coe - STScI 35Jan 24, 2013
6σ
7σ
6σ 10σ
15σ
12σ
J-band
MACS0647-JD only appears in the two reddest Hubble filters
JD = “J-band dropout”
Visible light Infrared light
Dan Coe - STScI 36Jan 24, 2013
MACS0647-JD is not visible in Spitzer images at longer wavelengths
This is good.Bright detections would have suggested a red less-distant galaxy as opposed to a blue more-distant galaxy.
The current Spitzer images are relatively shallow.By observing deeper, we can hope to detect MACS0647-JD and measure its age and dust content (pollution level).
Hubble Spitzer
Dan Coe - STScI 37Jan 24, 2013
Redshifted or just red
(old / dusty)?
Starburst
Elliptical
Spiral
AgeGalaxies do come in different colors, but the observed colors
of MACS0647-JD can only be
explained by a very distant galaxy
Dan Coe - STScI 38
MACS1149-JDz ≈ 9.6 (490 Myr)
Wei Zheng et al.Nature 489, 406
Jan 24, 2013
Another candidatein the first 500 Myr
Dan Coe - STScI 39
Ultra Deep Field 2012
• 2004 – ACS (optical) + NICMOS (infrared)• 2009 – WFC3/IR (better infrared)
– released in 2012 as “ eXtreme Deep Field ”• 2012 – WFC3/IR over twice as deep
Jan 24, 2013
R. Ellis
Dan Coe - STScI 40
Ultra Deep Field 2012
7 candidates for galaxies observed in
first 570 million years,including a new
candidate for most distant galaxy known
Jan 24, 2013
Dan Coe - STScI 41Jan 24, 2013
Revised to z ≈ 11.9 by R. Ellisbased on F140W non-detection,
though they caution it may be a less distantextreme emission line galaxy
Another candidate for most distant galaxy known
UDF12-3954-6284 z = 11.9+0.3
-0.5 (370 Myr after big bang)
F105W F140W F160Wonly detected in the reddest Hubble filter
Originally identified in 2011 by R. Bouwens who estimated z = 10.3 ± 0.8 (450 Myr)
R. Ellisadded in 2012:
Dan Coe - STScI 42
So what is the most distant galaxy yet known?
Jan 24, 2013
“Mr. Hubble says that trophies are for people with self-esteem issues.”
Dan Coe - STScI 43
Most distant galaxy candidates discovered to dateRedshift(68% CL)
age of universe
object F160W AB magnitude
Flux (nJy) reference field /survey
11.9 +0.3-0.5 370 Myr UDF12-3954-6284 29.3 ± 0.2 7 Ellis13,
Bouwens11UDF12
10.8 ± 0.3 420 Myr MACS0647-JD 25.9, 26.1, 27.3 162 - 42 Coe13 CLASH
9.6 ± 0.2 490 Myr MACS1149-JD 25.7 ± 0.07 194 Zheng12 CLASH
9.5 +0.4-0.8 500 Myr UDF12-4106-7304 29.7 ± 0.3 5 Ellis13 UDF12
9.5 +0.4-0.7 500 Myr UDF12-4265-7049 29.7 ± 0.4 5 Ellis13 UDF12
9.2 +0.4-0.6 520 Myr MACS1115-JD 26.2 ± 0.2 115 Bouwens13 CLASH
9.0 +0.3-0.8 540 Myr MACS1720-JD 26.9 ± 0.3 66 Bouwens13 CLASH
Jan 24, 2013
Redshift age of universe
object AB magnitude reference
7.215 (spec-z) 720 Myr SXDF-NB1006-2 24.6 narrow band Shibuya12
7.213 (spec-z) 720 Myr GN-108036 25.5 Y (1μm) Ono12
Highest redshifts spectroscopically confirmed
Dan Coe - STScI 44
UDF + CLASH provide our first views of first 500 million years,but more observations are required to constrain cosmic evolution
Jan 24, 2013Ellis et al.
Cosmic star formation rate density
500 400800 6001Gyr Myr after big bang1.5Gyr
Jan 24, 2013 Dan Coe - STScI 45
Lensing is more efficient atdiscovering the most distant galaxies
blank field
lensed
Bright Faint
Time required with Hubble
Log galaxiesper
Hubble image
Dan Coe - STScI 46
Simone Kay
“Blank” Field Lensed
To lens or not to lens?
Jan 24, 2013
Magnified:more efficient,detailed study
Unobstructed view:luminositiesmore certain
We can map out thelensing dark matter
well but not perfectly
Dan Coe - STScI 47
ACS
We have decided to do both! Hubble will observe lensed and “blank” fields simultaneously in parallel.
WFC3/IR
cluster core
“blank” field
Jan 24, 2013
Dan Coe - STScI 48
ACS
Swap cameras 6 months later / earlier
WFC3/IR
“blank” field
cluster core
Jan 24, 2013
Dan Coe - STScI 49Jan 24, 2013
The Frontier Fields: first 4 of 6 selectedMACS0717+37
Pandora’s ClusterAbell 2744
Abell 370
MACS0416-24
http://www.stsci.edu/hst/campaigns/frontier-fields/
Hubble will obtain the first ever deep lensed IR images,while simultaneously observing more “blank”deep fields in parallel
nearly 2 monthson Hubbleover 3 years:Fall 2013 – Fall 2016
observations of final 2 cluster-field pairs subject to approval
dark mattergas
Dan Coe - STScI 50
The Frontier Fields will help address questions about the early universe
• Do we find the numbers of galaxies we expect, or do we observe more dramatic evolution?
• Were there enough galaxies to reionize the early universe?
• Can we detect any pristine galaxies yet to be enriched by supernova explosions?
Jan 24, 2013
Dan Coe - STScI 51
Hubble cannot observe the first 300 million years.The James Webb Space Telescope is required
to observe and study the first galaxies.
Jan 24, 2013
Hubble’s limit:300 million
years = redshift 13
Dan Coe - STScI 52
CLASH and the UDF are performing frontier science, discovering galaxy candidates in the first 500 Myr
with Hubble and Spitzer
• The Hubble Frontier Fields will build upon these efforts, improving the galaxy census300 – 500 Myr after the big bang
• The James Webb Space Telescope is required to observe the first galaxies at earlier times
Jan 24, 2013
Dan Coe - STScI
Thank you
Jan 24, 2013
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