Finding our Origins with the Hubble and James Webb Space Telescopes

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Finding our Origins with the Hubble and James
Webb Space Telescopes

• Jonathan P. Gardner
• NASAs Goddard Space Flight Center

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Sound Check
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Finding our Origins with the Hubble and James
Webb Space Telescopes

• Jonathan P. Gardner
• NASAs Goddard Space Flight Center

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Astronomical Search For Origins
First Galaxies
Big Bang
Life
Galaxies Evolve
Planets
Stars
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Beginnings are Important (Origins)
David Jonathan Gardner, June 16, 2005
David Jonathan Gardner, June 16, 1998
... So Are Changes(Evolution)
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A Brief History of Time
Galaxies Evolve
Planets, Life Intelligence
First Galaxies
Atoms Radiation
Particle Physics
Big Bang
Now
3 minutes
300,000 years
400 million years
1 billion years
13.7 billion years
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Edwin P. Hubble(the man, not the telescope)

• The Spiral Nebulae are Island Universes
• The Universe is Expanding
• Classification of Galaxies

Edwin P. Hubble, 1889-1953
Which is further away?How can you tell?
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Distances
If you know somethings intrinsic luminosity, and
measure its apparent luminosity, you know how far
away it is.
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Astronomer's Toolbox 1Measuring Distances
Cepheid Variable Stars known period-luminosity
relation.
Astronomers can measure distances if they know
the intrinsic luminosity.
Suitable for nearby galaxies
Supernovae known maximum luminosity. Suitable
for distant galaxies.
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Hubble Discovers the Universe
Cepheids in the Andromeda galaxy showed it is 8
times further than the most distant star in our
Galaxy. ? Island Universes!
Hubble at Mount Wilson telescope
Planetary Nebula are within our Galaxy.
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The Doppler Shift - Sound
OBJECT RECEDING LOW-PITCHED WAVES
OBJECT APPROACHING HIGH-PITCHED WAVES
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Astronomer's Toolbox 2Doppler Shift - Light
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Hubbles Law
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Expansion of the Universe
Early time
Later
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Astronomer's Toolbox 3Looking Backwards in Time
Far, Far Away means Long, Long Ago

• Distance Light travel time Seeing the past.

1 Billion light years away 1 Billion years ago
Time
1 Million light years away, 1 Million years ago
Distance
Here Now
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Put the tools together

• To see backwards in time, to when the Universe
  was younger
• We measure the Doppler Shift (Redshift)
• Hubbles law tells us how far away it is
• The speed of light tells us how long ago the
  light was emitted.

• On average, more distant galaxies are fainter,
  so
• To look backwards in time, you need a powerful
  telescope.

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The Hubble Sequence

• Hubble classified nearby (present-day) galaxies
  into Spirals and Ellipticals.

• The Hubble Space Telescope can extend this to the
  distant past.

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The Hubble Deep Fields

• The Hubble Space Telescope has been pointed at
  one location in the sky for more than 500 hours,
  with more planned.

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Deepest View of the Universe

• Discoveries
• History of star-formation in the Universe.
• Distant supernova confirms accelerating Universe.
• Distant galaxies are compact, train wrecks.

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History of Star Formation in the Universe
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Distant Supernova Confirms Accelerating Universe

• Pressure from Dark Energy accelerates the
  cosmic expansion, overcoming gravity

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Distant Galaxies are Train Wrecks

• Trace construction of Hubble sequence

• How do train wrecks become spirals and
  ellipticals?

By Merging!
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Galaxy Mergers
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The First Galaxies

• What did the first galaxies to form look like?
• They are very distant, and very faint.

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Infrared Light

• Light from the first galaxies is redshifted from
  the visible into the infrared.

• Most of the Suns energy is visible light

• Infrared is heat radiation

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How to win at Astronomy
1010
Photographic electronic detection
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Telescopes alone
HST
CCDs
Big Telescopes with Sensitive Detectors in Space
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Sensitivity Improvement over the Eye
Photography
1796
1926
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1665
102
1610
Rosses 72
Mount Wilson 100
Mount Palomar 200
Soviet 6-m
Shorts 21.5
Herschells 48
Slow f ratios
Huygens eyepiece
Galileo
1600
1700
1800
1900
2000
Adapted from Cosmic Discovery, M. Harwit
Year of observations
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A Large Cold Telescope in Space
James Webb Space Telescope
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HST vs. JWST - temperature
-225 Celsius,-370 Fahrenheit
Room Temperature
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HST vs. JWST - size
How do you put a 6.5 meter mirror in a 4 meter
rocket?
2.4 meter diameter
6.5 meter diameter
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HST vs. JWST - orbit
How will JWST get there?
375 miles up
Second Lagrange Point,1,000,000 miles away
Ariane 5
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Astronomical Search For Origins
First Galaxies
Big Bang
Life
Galaxies Evolve
Planets
Stars
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(No Transcript)
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Finding our Origins with the Hubble and James
Webb Space Telescopes

• Jonathan P. Gardner
• NASAs Goddard Space Flight Center