Warm up 9/14/2016 1.What is the difference between rotation and revolution? 2.What are Kepler’s Three Laws of Planetary Motion and why are they important?

Answers: 1. Rotation refers to the Earth’s spin around its internal axis, while revolution refers to the Earth’s orbital motion around the sun. The Earth rotates on its axis once every 24 hours and revolves around the sun once every 365.25 days.

2. KEPLER’S FIRST LAW: (ORBIT) Planets move in elliptical orbits with the Sun at one focus. KEPLER’S SECOND LAW: (AREA) When the planet is closer to the sun, it moves faster, sweeping through a longer path in a given time. KEPLER’S THIRD LAW: (PERIOD) The square of the orbital period of any planet is proportional to the cube of the semi major axis of its orbit The three laws described the motion of the planets across the sky.

Study Jam to review 1.1.2 http://studyjams.scholastic.com/studyjams/jams/science/solar-system/day-on-earth.htm

The Sun’s Energy 1.1.3 5

Essential Question… What process powers the Sun and what forms of Energy does that process produce?

The Sun The Sun makes up 99% of the mass of the solar system! About 70% hydrogen and 28% helium by mass everything else ("metals") amounts to less than 2%.

The Sun’s Atmosphere The Sun’s atmosphere consists of the Photosphere the lowest layer 400 km thick Hot! (5800 K) the visible surface of the Sun http://www.solarviews.com/images/VSS00031.jpg

The Sun’s Atmosphere The Sun’s atmosphere consists of the Chromosphere Above the photosphere 2500 km thick Very hot! (30,000 K)

The Sun’s Atmosphere The Sun’s atmosphere consists of Corona Extends several million km from the top of the chromosphere Very low density – only visible during an eclipse Extremely hot! (1 to 2 million K)

The Sun's power (about 386 billion mega Watts) is produced by nuclear fusion reactions.

Nuclear Fusion Nuclear fusion does two things: it converts hydrogen into helium and it converts mass to energy. Albert Einstein’s theory of special relativity explains this. The difference in mass is converted to energy by Einstein's famous equivalence E=mc2.

Nuclear Fission vs Nuclear Fusion Nuclear Fission – nuclei split Process used in nuclear power plants Nuclear Fusion – nuclei combine The way in which the Sun produces energy These nuclear reactions are different than combustion. Combustion = a chemical reaction where energy is released when one substance is changed into another. Wood turns into charcoal/ash when it burns. Nuclear = a reaction on an atomic level where atoms are either split apart or fused together

The Sun’s Energy a. Electromagnetic radiation consists of … electric and magnetic disturbances that travel through space as waves. b. Electromagnetic radiation includes… radio waves, microwaves, infrared energy, visible light, ultraviolet radiation, x-rays, and gamma rays

c. The electromagnetic spectrum organizes the forms of EM energy d. Electromagnetic energy is classified by wavelength and moves at the speed of light

The Electromagnetic Spectrum…

The Electromagnetic Spectrum The electromagnetic spectrum represents the range of energy from low energy, low frequency radio waves with long wavelengths up to high energy, high frequency gamma waves with small wavelengths.

The Electromagnetic Spectrum As you go from left  right, the wavelengths get smaller and the frequencies get higher. This is an inverse relationship between wave size and frequency. (As one goes up, the other goes down.) This is because the speed of ALL EM waves is the speed of light (300,000 km/s).

The Waves (in order…) Radio waves: Have the longest wavelengths and the lowest frequencies; wavelengths range from 1000s of meters to .001 m Used in: RADAR, cooking food, satellite transmissions

Infrared waves (heat): Have a shorter wavelength, from Infrared waves (heat): Have a shorter wavelength, from .001 m to 700 nm, and therefore, a higher frequency. Used for finding people in the dark and in TV remote control devices Visible light: Wavelengths range from 700 nm (red light) to 30 nm (violet light) with frequencies higher than infrared waves. These are the waves in the EM spectrum that humans can see. Visible light waves are a very small part of the EM spectrum!

RedOrangeYellowGreenBlueIndigoViolet Visible light is a small portion of this spectrum. This is the only part of this energy range that our eyes can detect. What we see is a rainbow of colors. RedOrangeYellowGreenBlueIndigoViolet ROY G BIV Light from the sun looks white, but it is really made up of all the colors of the rainbow. A prism is a specially shaped crystal. When white light shines through a prism, the light is separated into all its colors.

Ultraviolet Light: Wavelengths range from 400 nm to 10 nm; the frequency (and therefore the energy) is high enough with UV rays to penetrate living cells and cause them damage. Although we cannot see UV light, bees, bats, butterflies, some small rodents and birds can. UV on our skin produces vitamin D in our bodies. Too much UV can lead to sunburn and skin cancer. UV rays are easily blocked by clothing. Used for sterilization because they kill bacteria.

X-Rays: Wavelengths from 10 nm to. 001 nm X-Rays: Wavelengths from 10 nm to .001 nm. These rays have enough energy to penetrate deep into tissues and cause damage to cells; are stopped by dense materials, such as bone. Used to look at solid structures, such as bones and bridges (for cracks), and for treatment of cancer.

Gamma Rays: Carry the most energy and have the shortest wavelengths, less than one trillionth of a meter (10-12). Gamma rays have enough energy to go through most materials easily; you would need a 3-4 ft thick concrete wall to stop them! Gamma rays are released by nuclear reactions in nuclear power plants, by nuclear bombs, and by naturally occurring elements on Earth. Sometimes used in the treatment of cancers.

Doppler Effect This apparent change in frequency due to the motion of the source (or receiver) is called the Doppler effect. The greater the speed of the source, the greater will be the Doppler effect.

As a wave source approaches, an observer encounters waves with a higher frequency. As the wave source moves away, an observer encounters waves with a lower frequency.

Solar Wind Solar wind is… A supersonic plasma that flows outward from the corona at high speeds It consists of charged particles or ions Solar wind bathes each planet in a flood of high-energy particles. (Which isn’t very good for us!)

Solar Wind

Earth’s Magnetic Field Earth’s magnetic field protects us from the solar wind by… deflecting these particles and trapping them in two huge rings called the Van Allen belts

Earth’s Magnetic Field (bow shock is a shock wave formed) (magnetosphere is the cavity formed by the Earth's magnetic field)

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