AIM: How was the Universe Created? Do Now: Which planet has the shortest day? Which planet rotates on its side? Which planet has the longest rotation?
What is the Universe? Everything that exists in any place. All space, all matter, all energy. What is the age of the Universe? Scientist believe the universe is billion years old.
What is a Galaxy? Grouping of billions of stars Billions of galaxies form the Universe.
What is known about our galaxy? Name: Milky Way Spiral 2- armed galaxy TOP VIEW SIDE VIEW Our Solar System
What is the Big Bang Theory? Theory that states that: All matter and energy in the universe was concentrated into a small area. huge explosion takes place b/c high density & high temp. planets form from atoms and particles of the explosion. Universe, Galaxies, solar system and planets all formed at the same time.
How do we know the Universe is still expanding? Proof: RED SHIFT Long wave radiation (microwaves) coming from all areas of the universe. Electromagnetic radiation from stars and celestial objects (ESRT 14) This shifting of wave lengths is called the Doppler effect shows a red shift Red wavelengths are long! Red shift - galaxies are moving away from us or expanding.
Let’s Review … What is a galaxy? What do we know about our galaxy? What is the Big Bang Theory? What is the Doppler Effect?
Aim: How do we know the Universe is still expanding? Do Now: Use the ESRT’s and list four characteristics of Alpha Centuri.
The shifting of wave lengths What is the doppler effect? Scientist have found that wavelengths are shifted to either the shorter or longer portion of the spectrum ESRT 14 Astronomers use the Doppler shifts to calculate precisely how fast stars and other celestial objects move toward or away from Earth.
When objects move away from you – wavelength becomes longer When objects approach you - wavelengths bunch up or become shorter Sound = high pitch Light = receive short wavelength of color - Blue Shift Sounds = low pitch Light = receive longer color of wavelength - Red Shift
Evidence for the big bang-doppler effect Stationary Red shift Blue shift Moving Away Moving Towards
How old is our solar system? Our Solar system – 1 star & 9 planets took about 100 million years to form. Age of Earth & Solar System = 4,600 Billion years old How do stars produce energy? they produce and emit their own energy in the form of heat and light by radiation.
Stars undergo nuclear fusion Hydrogen atoms are changed to Helium atoms. This nuclear fusion produces energy in the form of radiation.
What is electromagnetic Energy? invisible waves that travel through space emitted by celestial objects. Stars emit visible light. ( violet the shortest and red the longest) each type of electromagnetic wave has a different frequency and a different wavelength. Violet / Blue / Green / Yellow / Orange / Red
Frequency - the # of waves that pass a point in a second. Wavelength - the distance from one crest to another crest. (crest = top of wave) ** Frequency and wavelength are inversely proportional ** High Frequency = short wavelength Low Frequency = long wavelength
Short wavelength, high frequency, hotter, more damaging, more intense. Long wavelength, low frequency, cooler, less damaging, less intense.
What is the electromagnetic spectrum? (ESRT 14) A model which shows the range of wavelengths from radio (longest) to gamma (shortest). What is it used for? to find the composition and movement of celestial objects.
What is a spectrum? A band of colors that visible light is made from. As visible light passes through a prism, the light is bent showing different colors. the spectrum created by gases as they burn is a fingerprint of that particular gas. WHY? each color has its own wavelength.
Summary 1) What is the Big Bang Theory? 2) What evidence is there for the big bang theory? 3) What is the Doppler Effect 4) What is the Electromagnetic Spectrum?