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Wilkinson Microwave Anisotropy Probe (WMAP). By Susan Creager April 20, 2006. Two theoretical principles of the Big Bang. General Relativity The Cosmological Principal. General Relativity. - PowerPoint PPT Presentation
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Wilkinson Microwave Anisotropy Probe
(WMAP)
By Susan Creager
April 20, 2006
Two theoretical principles of the Big Bang
• General Relativity
• The Cosmological Principal
General Relativity
• Gravity is not a field, but a distortion of space and time. This applies to bodies at motion as well as at rest. Its speed is the speed of light.
The Cosmological Principle
• Matter is distributed evenly when averaged over large areas.
Three theories of the shape of the universeThree theories of the shape of the universe
Observational Tests of the Big Bang
• Expansion of the Universe
• Abundance of the light elements H, He, Li
• The Cosmic Microwave Background Radiation
Cosmic Background Radiation – the radiant heat left over from the Big Bang. It formed a few thousand years after the Big Bang before
stars and galaxies.
Why Study CMBR?
Visible Stars
• 10-100 years ago
Andromeda Galaxy
• 2.5 million years ago
Hubble Telescope
• A few billion years ago
What is in the universe?
• Radiation – massless or nearly massless particles that travel at the speed of light. These include photons and neutrinos.
• Baryonic matter – protons, neutrons, and electrons• Dark matter – not observed, but suspected• Dark energy – the only form of matter that can cause the
universe to speed up
Composition of the UniverseComposition of the Universe
Wilkinson Microwave Anisotropy Probe (WMAP)
3.8 x 5 meters
840 Kg
Its purpose is to map the temperature fluctuations of the CMBR.
WMAP – launched in June 2001
Launched in 2001, it was originally meant to be a 27 month mission. NASA later extended its time frame.
Original Logo – Wilkinson was added preceding MAP to honor Dr. David Wilkinson, a member of the team and a pioneer in cosmic background
radiation.
Anisotropy
• Fluctuations in cosmic background radiation. CMBR is very cold – only 2.725 degrees above absolute zero.
• Fluctuations may range very slightly from 2.7251 and 2.7249 degrees in one portion of the sky.
• Red areas are warmer• Blue areas are cooler
• White lines show “polarization” direction of old light
Early cosmic background radiation
Material is gravitationally pulling together
Stars are forming
Galaxies are forming
The present sky
References
• http://map.gsfc.nasa.gov/
• http://en.wikipedia.org/wiki/Wilkinson_Microwave_Anisotropy_Probe
• http://www.daviddarling.info/encyclopedia/M/Microwave_Anisotropy_Probe.html