Our Sun

Life Cycle of Our SunAbout 4.6 billion years ago a great swirl of gas and dust some 15 billion miles across in this location in space and began to condense forming our Sun.Virtually 99.9 percent of the mass of our Solar System is the Sun.Our Sun has lived almost 5 billion years of its life and will lived approximately 5 billion more as a medium star.In about 4 billion years our Sun will begin to increase in temperature.Then it will expand and cool to a Red Giant in 5 billion years.In around 10 billion years from now, our Sun will become a hot white dwarf then most likely burn out as a Black Dwarf.

Interior of our Sun

CoronaOuter

Atmosphere

The Sun

Surface of the Sun

Lower Atmosphere

Layers of the Sun• Photosphere (6000°C)-Sun’s Transparent

Plasma(ionized gas) Visible Surface• Chromo sphere(10,000°C)- Sun’s

Atmosphere • Corona(1,000,000°C) Outer most layer of

atmosphere• Sun’s Interior– Convective Zone- area of convection currents

where the heat is constantly circulating.– Radiative Zone-energy is transmitted through

radiation.– Core (1.5x107°C)-Nuclear Fusion occurs

creating energy.

•Nuclear FusionThe process by which hydrogen atoms are converted in to helium atoms and release an enormous amount of energy.*Every second 4.5 million tons of solar mass is converted to radiant energy in the core of the sun.

Hydrogen

Hydrogen

Size of our SunThe Sun is about 149 million km (93 million miles) from Earth. The mass of the Sun is about 750 times the mass of all the objects in the solar system together.

It is 99.9% of all mass in our solar system.

Rotation = 34 Earth DaysRevolution= 25 Earth days

Diameter 864,900milies (1.4 million km)

Distance from Earth= 93million miles (149.6 million Km)

Mass= 333,000 times the mass of earth

•109 Earth’s would fit across the diameter of the sun.•The interior of the Sun could hold over 103 million Earth’s

Size of Our Sun and our OrbitThe Earth’s orbit around the Sun is an “ellipse”, flattened oval. This causes us to have moments when we are closing to or further away from the sun.

The Earth-Sun distance varies by about 3%, or roughly 5 million km (3 million miles), over the course of a year.

Aphelion- point when the Earth furthest away from the sun (July)*Remember “A” for “Away”

Perihelion-point when the Earth is closest to the sun. (January)

Question of the Day:Why do we have seasons on Earth?

Exterior of our Sun

Solar Flare

Solar Prominence

SunspotsSolar Wind

Solar Prominence

Solar prominences are large arch-shaped structures observable in the solar corona. These often have a twist and occasionally become unstable, ejecting plasma and magnetic flux out from the sun.

Solar Wind- A continuous stream of high energy particles shot from the Sun’s Corona.

Earth

Earth’s Magnetosphere

Solar Wind

Earth’s Magnetosphere: The Earth’s invisible magnetic field.This field attract solar particles from the sun that could destroy all life on Earth.The field forms around the Earth’s magnetic poles, which rotate every 10,000 years. Our magnetic poles are shifting right now and will change possibly within your lifetime.The earth’s magnetic field is believed to be caused by the fluid motion of the outer molten core caused by the earth’s rotation acting like a dynamo generating a magnetic field in the axial direction.

Solar Wind can also interfere with commun-ication devices on Earth, such as cell phones.

Aurora Borealis-(Northern Lights)when charge particles from the sun are attracted to our magnetic poles.

SunspotsThese are darker, cooler areas on the surface of the sun.They may be as small as 16 kilometers or as large 160,00kilometers but usually around twice the size of the Earth.Usually around 4500°C.Activity on our Sun varies over a roughly 11-year cycle. At the beginning of a cycle, sunspots are sparse. The spots gradually increase over several years, peak, and then decrease over the next several years, with spots from old and new cycles often occurring simultaneously as a new cycle starts. At the end of October 2008, another batch of sunspots appeared, most of them belonging to a new cycle!

Solar FlaresThis is a solar storm explosion on the surface of the sun.Gas and energy is shot from the surface with a temperature of 12,000°C.Solar Flares are much larger than our Earth.Solar Flares can interact with Earth’s atmosphere causing from problems with communication and cell phone use.Example: Air Force One 1984 with President Regan, while in-route to China (during the Cold War!)

Size of Earth