FORMATION OF THE UNIVERSE

1. FORMATION OF THE UNIVERSE Application of space technologies to the study of changes in Earth and its systems

2. Cosmology and Astronomy • Cosmology is the study of the origin, evolution, properties, and processes of the universe. • Astronomy study of things outside of earth (stars, planets, moons, comets, and galaxies)

3. How did our Universe form? • It all started with a Big Bang • https://www.youtube.com/watch?v=CMSYv_Z4SI8

4. HOW DID OUR UNIVERSE FORM? P390 • The Big Bang Theory suggests 13.7 billion years ago, everything in the universe was squeezed into a very small volume, then an enormous explosion — a big bang — caused the universe to start expanding rapidly. • All the matter and energy in the universe, even space itself, came out of this explosion.

5. What happened then? Just minutes after the big bang, the following had already formed: • the light elements, such as helium • the forces of nature, such as gravity • the beginnings of galaxies • Some parts of the cloud moved faster than others, but all parts moved outward, away from the center. • As the particles moved, they condensed into billions of galaxies. • Universe continues expand.

7. What’s in our Universe? • Galaxies - collection of stars, intersteller gas, dust and dark matter. Our galaxy is the Milky Way. • Nebulae - a cloud of gas and dust from which stars (and our solar system) are formed • Stars –luminous balls of gases, mostly hydrogen and helium, held together by its own gravity • Planets – astronomical bodies orbiting a star • Black Holes – region in spacetime with such strong gravitational pull that particles of matter and light cannot escape from inside it. • Dark Matter - hypothetical form of matter that is thought to account for approximately 85% of the matter in the universe.

8. Structure of the Universe • Earth is part of the planetary system called the solar system. • A planet is part of a planetary system. • A planetary system is part of a galaxy. • A galaxy is part of a galaxy cluster. • Our solar system is part of the Milky Way galaxy.

9. EVIDENCE FOR THE BIG BANG • Expansion of the Universe. • Cosmic Background Radiation.

10. How do we know the Universe is still Expanding? • Evidence for Expansion: Red Shift • Astronomers observed that light from distant objects in the universe is redshifted (shift in the frequency of light towards red color), which tells us that the objects are all receding away from us. • This is true in whatever direction you look at: all the distant galaxies are going away from us.

11. Visible Light • We see stars and galaxies because they emit (give off) light. • Spectrum of Visible Light contains ALL colours. • Each colour has it’s own wavelength.

12. Red Shift • Red has longest wavelength, violet shortest • When an object moves away from us, the light is shifted to the longer (red) end of the spectrum, as its wavelengths get longer (Redshift) • If an object moves closer, the light moves to the blue end of the spectrum, as its wavelengths get shorter. (Blueshift)

13. Red Shift

15. Doppler Effect explains Red Shift p371 • Ever notice how a police siren or a horn honking sounds different when it is coming toward you, compared to as it passes and starts moving away from you?

16. Doppler Effect explains Red Shift p371 • Something similar happens to sound waves when a source of sound moves relative to an observer. • Doppler Effect: The apparent change in the frequency of a wave caused by relative motion between the source and observer. • Sound effect first described by Christian Andreas Doppler in the 1800s. • Video 3min • https://www.youtube.com/watch?v=h4OnBYrbCjY

17. The Doppler Effect • Based on this, what do you think red shift (or blue shift) means?

18. Red Shift first described by Edwin Hubble • American astronomer Edwin Hubble (who the Hubble Space Telescope is named after) was the first to describe the redshift phenomenon and tie it to an expanding universe. • In 1929, his observations showed that nearly all galaxies he observed are moving away.

19. Hubble’s Law A. The Milky Way is expanding. B. The Universe is expanding. C. The redshifts of distant galaxies are proportional to their distances from us.

20. 2. Cosmic Background Radiation • Unexpected radiation has been observed coming from all directions in space, suggesting it may be a remnant of the radiation from the initial “Big Bang” explosion.

21. 2. Cosmic Background Radiation • Radiation: Energy transmitted in waves that can be picked up from every part of space. • First discovered by chance in 1965 by a radio telescope and may be the remains of the radiation that was given off by the original Big Bang event. • Space probes have mapped background radiation • Cosmic background radiation suggests that the early universe was dominated by a radiation field, a field of extremely high temperature and pressure.

22. How was CMB Detected? • On May 20, 1964, American radio astronomers Robert Wilson and Arno Penzias discovered the cosmic microwave background radiation (CMB), the ancient light that began saturating the universe 380,000 years after its creation. pretty much by accident. • Bell Labs' Holmdale Horn Antenna in New Jersey picked up an odd buzzing sound that came from all parts of the sky at all times. • The noise puzzled Wilson and Penzias, who did their best to eliminate all possible sources of interference, even removing some pigeons that were nesting in the antenna.  • The two radio astronomers won the 1978 Nobel Prize in physics for their work, sharing the award with Soviet scientist Pyotr Kapitsa. • Source: https://www.space.com/25945-cosmic-microwave-background-discovery-50th-anniversary.html

24. Assignment: Peer Teaching • Alone or in Groups of 2-3: Research Technologies and how they have led to discoveries in space. • Time line: • Library time: June 11/12, June 13/14 – This may change ( but still two library days) • Present as a group to another group: June 17/18