BCScience9 Ch 10

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10.1 Explaining the Early Universe

Astronomers: People who study objects in space

Celestial bodies: Objects in space

Edwin Hubble discovered that galaxies farther from our galaxy were moving away from each other faster than galaxies closer to ours (the closer to us, the slower the galaxies move away from us).

The theories of astronomers improve as technology improves.

Hubble's Proposal

The universe is expanding in all directions. Model: raisin bread (Dough = universe, raisins = galaxies). As the universe expands, the distance between all galaxies increases.

Red Shift Analysis

How Edwin Hubble came to his proposal

Electromagnetic Waves

Electromagnet radiation: Energy that is carried or radiated in the form of waves.

Examples: visible light, microwaves, radio waves, x rays.

Electromagnetic radiation is a spectrum

Spectral Patterns

Spectrum: A pattern of colours (rainbow)

Spectroscope: An optical instrument that acts like a prism to separate light into its basic component colours

Light from stars split through spectroscope and produce patterns

Blue-shifted: Moving toward Earth

Cosmological Red Shift

Red shift: Spectral lines shift toward red end (wavelengths lengthened)

Cosmological red shift: Wavelengths of radiated light are constantly lengthened (light crosses expanding universe)

As space expands, so do the waves of radiation as they travel from the distant galaxies

The Big Bang Theory

Big Bang theory: A theory that proposes that the universe formed approximately 13.7 billion years ago when an unimaginably tiny volume of space suddenly and rapidly expanded to immense size

Cosmic Background Radiation

Radiation: Transmission of energy in waves

Background noise/satellite interference monitoring microwave radiation in space

Evidence of Big Bang

Additional Supporting Evidence

COsmic Background Explorer (satellite) mapped cosmic background radiation data (launched by National Aeronautics and Space Administration)

New spacecraft: Wilkinson Microwave Anistropy Probe , more precise, confirmed data gathered by COBE