Exploring the Universe

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Exploring the Universe

• Nicholas White
• NASA Goddard Space Flight Center

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M101 Pinwheel Galaxy from HST
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Exploring the Universe with Hubble Ultra-Deep
Field reveals galaxies forming and evolving
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Exploring at the Edge of a Black Hole
The Chandra X-ray Deep Field
What happens close to a Black Hole?
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The Birth of Black Holes!SWIFT
Distant Gamma Ray burst
Nearby Gamma ray burst
Swift
SWIFT detects the most distant explosion 12.8
billion light years away!
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Exploring the beginning of Time!
Baby picture of the Universe from the Wilkinson
Microwave Anisotropy Probe (WMAP)
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History of the Universe
What powered the Big Bang?
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Using Supernovae to Measure the Expansion of the
Universe
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Exploring the Dark Side of the Universe
We do not know what 95 of the Universe is made
of!
70 is a mysterious Dark Energy that is causing
the expansion of the Universe to accelerate
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Exploring other Solar Systems

• How many planets are there around nearby stars
• Where are the nearest Terrestrial Planets?
• Does any planet outside the Earth harbor life?

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Detecting and Characterizing Exo-Solar Planets
Spitzer
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The NASA Goddard Space Flight Center Exploration
of the Universe Astrophysics Future Observatories
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Gamma Ray Large Area Space Telescope
View along the relativistic jets from Black Holes
Cosmic accelerators Search for the gamma-ray
signature from the decay of dark matter particles
GLAST is a joint NASA-DoE program, a pathfinder
for the future
Launch Fall 2007
30-100 times improved sensitivity for high energy
gamma rays
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HST at the apex of its capabilities after the
fourth servicing mission
BatteriesGyrosFGS Sustained HST Lifetime
through 2008 to 2013
Wide Field Camera3 Advanced Camera for Surveys
Most powerful HST imaging
Cosmic Object Spectrograph repaired ST Imaging
Spectrograph Full set of spectroscopy tools for
astrophysics

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HST Servicing Mission 4 (SM4) Configuration
(Preliminary)
Soft Capture Mechanism
Cosmic Origins Spectrograph
Rate Sensor Units
Fine Guidance Sensor
Multi-use Logistic Equipment Carrier
Batteries
Wide Field Camera 3
Flight Support System
Orbital Replacement Unit Carrier
Super Lightweight Interchangeable Carrier
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Evolution of the Cosmic Web of Dark Matter
Quasar absorption lines trace the cosmic web
of material between the galaxies

• Hydrogen and helium constitute 99 of ordinary
  matter in the universe, called baryons
• Most of the baryons are currently unseen and
  should reside in the space between galaxies (the
  IGM)
• The baryons are mixed with Dark Matter and trace
  its distribution
• We study this distribution by detecting
  absorption lines from baryons in the spectra of
  quasars
• COS will expand the number of quasars, hence
  sight lines explored, by 2 orders of magnitude,
  thus mapping Dark Matter to high accuracy

• Visualization concept from Schiminovich Martin
• Numerical simulation from Cen Ostriker (1998)
• Songaila et al. (1995) Keck spectrum adapted by
  Lindler Heap

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Wide Field Camera 3
Near-IR

• Capabilities
• Imaging from 2000 Å to 1.7 ?m
• Slitless spectroscopy
• Huge improvement in near-UV, near-IR imaging

Ultraviolet
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The JWST Observatory The Exploration Time Machine
Telescope
Primary Mirror (PM)
Instrument module
Secondary Mirror (SM)
Cold, space-facing side
Warm, Sun-facing side
Spacecraft Bus
Sunshield
Launch 2013
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JWST Science Objectives versus Cosmic History
Star Planet Formation
Galaxies Evolve
Origin of Life Intelligence
First Galaxies
Atoms Radiation
Particle Physics
Big Bang
Now
3 minutes

• Study the birth and evolution galaxies
• See First Light Objects
• Galaxy Evolution
• Study star and planet formation
• Coronagraphs will study of debris disks and
  Extrasolar Giant Planets
• Transit spectroscopy of planets

300,000 years
200 million years
1 billion years
13.7 billion years
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JWST Simulated Deep Field
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End of the dark ages first light and reionization

• What are the first galaxies (beyond those seen by
  Hubble at z 6)?
• When did reionization occur?
• Once or twice?
• What sources caused reionization?

• Ultra-deep field
• Spectrum of distant quasars
• Studies of faint galaxies

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The assembly of galaxies

• Where and when did the Hubble Sequence (of galaxy
  shapes) form? (probably after redshift 6)
• How did the heavy elements form?
• What theories explain the shapes and histories of
  galaxies?
• What about star-forming galaxies and giant black
  holes?

Galaxies in GOODS Field

• Wide-area imaging survey
• Spectroscopy of thousands of galaxies
• Targeted observations of extreme galaxies

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Planetary systems and the origins of life

• How do planets form?
• Are exosolar systems like our own?
• How are habitable zones established?
• Detection of planets via debris disks
• Directly image very young planets
• Indirectly detect planets via their footprints
  in debris disks

Visible (HST)
Spitzer (24 ?m)
JWST (20 ?m)
Fomalhaut

• Exosolar giant planets
• direct imaging by blocking stars light
• Spectra of organic molecules in disks, comets
  and Kuiper belt objects in outer solar system
• Atmospheric composition of exosolar planets
• Observe transits of planets

Titan
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Full-scale Mockup of JWST
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National Aeronautics and Space Administration

• What powered the Big Bang?
• What happens at the edge of a Black Hole?
• What is Dark Energy?

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Late 19th Century . . .

• Many physicists were certain that our
  understanding of the physical Universe was almost
  complete
• But there remained a few little problems

• ? The speed of light seemed to be independent of
  the reference frame in which it was measured
• ? Hot objects predicted to radiate infinite
  amounts of energy (clearly contradicted by
  experiments! UV catastrophe)

Solutions revolutionized physics Theory of
Relativity and Quantum Mechanics were born!
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The Theory of Relativity

• Einstein changed the way we think of the
  Universe
• The speed of light is the ultimate speed limit.
• Time passes more slowly for observers traveling
  at high speeds or near a massive body.
• Light rays can be bent passing near a massive
  body.

GR is a very rich and mathematically complex
theory ? many surprises in store!
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Einsteins Predictions

• Three startling outcomes of Einsteins general
  relativity
• ? The expansion of the Universe (from a Big
  Bang)
• ? Black holes
• ? A Cosmological Constant acting against the
  pull of gravity

Observations confirm these outcomes . . .
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Completing Einsteins Legacy

• Einsteins legacy is incomplete, his theory fails
  to explain the underlying physics of the very
  phenomena his work predicted and to connect
  General Relativity to quantum mechanics
• We are on the threshold of a breakthrough
  comparable to Einsteins discoveries one century
  ago . . .

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What happens at the edge of a black hole?
How do these gravitational sinks power such
powerful outflows?
Is Einsteins theory still right in these
conditions of extreme gravity? Or is new physics
awaiting us?
Ultimate goal is to image a black hole!
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What Powered the Big Bang?
Ultimate goal is to directly detect the Big Bang!
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What is Dark Energy?
Solving this mystery may fundamentally change our
view of the Universe!
Supernovae
Energy Density
Cosmic Microwave Background
Clusters of galaxies
Matter Density
Multiple approaches needed to independently
measure with high precision the expansion of the
Universe A key issues is whether the Dark Energy
is a constant or evolves with time
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Beyond Einstein Program
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Constellation-X LISA

• Constellation-X will use X-ray spectroscopy to
  observe
• Track matter spiraling into Black Holes
• The effects of Dark Matter and Dark Energy
• The Cycles of Matter and Energy

• LISA will search for Gravitational Wave Signals
  from
• Merging Black Holes
• Compact binaries in our galaxy
• The background radiation from the big bang

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Constellation-X Science Goals

• Black Holes
• Observe matter spiraling into Black Holes test
  the predictions of General Relativity
• Study distant/faint sources to trace the
  evolution of Black Holes with cosmic time
• Dark Matter and Dark Energy
• Use clusters of galaxies to trace the amount and
  evolution of Dark Energy
• Determine the spatial distribution of Dark
  Matter in galaxies and galaxy clusters
• Origin of the Elements, New States of matter,
  Cosmic Feedback
• Investigate the influence of Black Holes on
  galaxy formation
• Search for the hot missing matter in the Cosmic
  Web
• Study behavior of matter at extreme densities
  magnetic fields using neutron stars

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What happens close to a black hole?

• Analysis of iron line variability (from orbital
  motion of disk reverberation effects) allows to
  to separate effects of
• Accretion disk physics
• Space-time geometry
• Requires superior collecting area of
  Constellation-X

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HST
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Gravitational Wave Astrophysics
Black holes orbiting each other emit
gravitational waves that cause them to merge to
create a single black hole
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LISA Overview

• The Laser Interferometer Space Antenna (LISA) is
  a joint ESA-NASA mission to design, build and
  operate the first space-based gravitational wave
  detector.
• The 5 million kilometer long detector will
  consist of three spacecraft orbiting the Sun in a
  triangular formation.
• Space-time fluctuations induced by gravitational
  waves are detected by using a laser-based
  Michelson interferometer to monitor the changes
  in separation between test masses in the separate
  spacecraft to very high accuracy (1/100th the
  size of an atom)

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Einstein Probes
Focused scientist led missions that each address
a single high priority science topic, with the
implementation approach selected by competition

• Joint Dark Energy Mission
• Determine the evolution of dark energy with time
• Identify the nature of dark energy
• Partnership between NASA and DOE
• Inflation Probe
• Study imprints of gravitational waves from
  inflation on the cosmic microwave background or
  large scale structure
• Determine when and how inflation occurred
• Black Hole Finder Probe
• To conduct a census of hidden black holes
• Gamma ray bursts as Cosmological Probes

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Exploring other Solar Systems

• How many planets are there around nearby stars
  and what are their properties?
• Where are the nearest Terrestrial Planets?
• Does any planet outside the Earth harbor life?

Precursor missions (Kepler, JWST, SIM) and ground
observations will refine the TPF design
parameters Terrestrial Planet Finder will detect
and characterize the light from terrestrial
planets around nearby stars
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Conclusion
How did the Universe begin? Does time have a
beginning and an end? Are we alone? The
questions are as old as human curiosity The
answers have always seemed beyond the reach of
science. . . until now!
http//universe.gsfc.nasa.gov