1. The Sun is the largest object in the solar system.
PROPERTIES OF THE SUN
The Sun is the largest object in the solar system.

2. PROPERTIES OF THE SUN
The Sun is the largest object in the solar system.
330,000 times more massive than Earth, 1048 times the mass of Jupiter.

3. PROPERTIES OF THE SUN
The Sun is the largest object in the solar system.
330,000 times more massive than Earth, 1048 times the mass of Jupiter.
99% of all the mass in the solar system is found in the Sun.

4. PROPERTIES OF THE SUN
The Sun is the largest object in the solar system.
330,000 times more massive than Earth, 1048 times the mass of Jupiter.
99% of all the mass in the solar system is found in the Sun.
Mostly plasma (super hot matter): 73.4% hydrogen, 25% helium.

5. PROPERTIES OF THE SUN
The Sun is the largest object in the solar system.
330,000 times more massive than Earth, 1048 times the mass of Jupiter.
99% of all the mass in the solar system is found in the Sun.
Mostly plasma (super hot matter): 73.4% hydrogen, 25% helium.
Similar to the composition of other stars, and the gas giant planets.

6. LAYERS OF THE SUN
ATMOSPHERE – Actually gets hotter as you go up from the surface of the Sun.

7. LAYERS OF THE SUN
ATMOSPHERE – Actually gets hotter as you go up from the surface of the Sun.
Lowest level is the photosphere, the part that we can see from Earth. About 5500°C.

8. LAYERS OF THE SUN
ATMOSPHERE – Actually gets hotter as you go up from the surface of the Sun.
Lowest level is the photosphere, the part that we can see from Earth. About 5500°C.
Middle level is the chromosphere, about 30,000°C. Only seen in a solar eclipse.

9. LAYERS OF THE SUN
ATMOSPHERE – Actually gets hotter as you go up from the surface of the Sun.
Lowest level is the photosphere, the part that we can see from Earth. About 5500°C.
Middle level is the chromosphere, about 30,000°C. Only seen in a solar eclipse.
Upper level is the corona, about 1 million to 2 million degrees C. Too faint to see except in a solar eclipse.

11. LAYERS OF THE SUN
ATMOSPHERE – Actually gets hotter as you go up from the surface of the Sun.
Lowest level is the photosphere, the part that we can see from Earth. About 5500°C.
Middle level is the chromosphere, about 30,000°C. Only seen in a solar eclipse.
Upper level is the corona, about 1 million to 2 million degrees C. Too faint to see.
Solar wind – charged particles or ions (electrons, protons, neutrons) stream out from the corona at high speed. Deflected or captured by Earth’s magnetic field.

14. SURFACE – Covered with convection currents the size of Texas.
LAYERS OF THE SUN
SURFACE – Covered with convection currents the size of Texas.

15. LAYERS OF THE SUN
SURFACE – Covered with convection currents the size of Texas.
Sunspots – dark, cooler spots on the surface caused by the Sun’s magnetic field.

16. LAYERS OF THE SUN
SURFACE – Covered with convection currents the size of Texas.
Sunpots – dark, cooler spots on the surface caused by the Sun’s magnetic field.
Solar flares and increased solar wind accompany sunspot activity – damage to satellites, change in weather.

17. LAYERS OF THE SUN
SURFACE – Covered with convection currents the size of Texas.
Sunpots – dark, cooler spots on the surface caused by the Sun’s magnetic field.
Solar flares and increased solar wind accompany sunspot activity – damage to satellites, change in weather.
Sunspot activity goes through an 11 year cycle where the number of sunspots increases.

18. LAYERS OF THE SUN
SURFACE – Covered with convection currents the size of Texas.
Sunpots – dark, cooler spots on the surface caused by the Sun’s magnetic field.
Solar flares and increased solar wind accompany sunspot activity – damage to satellites, change in weather.
Sunspot activity goes through an 11 year cycle where the number of sunspots increases.
The Sun has just passed the high point for sunspot activity.

19. LAYERS OF THE SUN
INSIDE THE SUN – Extremely high pressure and temperature inside the core of the Sun causes nuclear fusion – hydrogen atoms combine and form helium atoms. ALL THE SUN’S ENERGY IS MADE IN THE CORE.

20. LAYERS OF THE SUN
INSIDE THE SUN – Extremely high pressure and temperature inside the core of the Sun causes nuclear fusion – hydrogen atoms combine and form helium atoms. ALL THE SUN’S ENERGY IS MADE IN THE CORE.
In the core, the density is 150 times greater than water and the temperature is 14 million degrees C.

21. LAYERS OF THE SUN
INSIDE THE SUN – Extremely high pressure and temperature inside the core of the Sun causes nuclear fusion – hydrogen atoms combine and form helium atoms. ALL THE SUN’S ENERGY IS MADE IN THE CORE.
In the core, the density is 150 times greater than water and the temperature is 14 million degrees C.
During fusion, a tiny amount of the mass of the hydrogen atoms is converted into energy: Einstein’s famous equation, E = mc2.

22. LAYERS OF THE SUN
INSIDE THE SUN – Extremely high pressure and temperature inside the core of the Sun causes nuclear fusion – hydrogen atoms combine and form helium atoms. ALL THE SUN’S ENERGY IS MADE IN THE CORE.
In the core, the density is 150 times greater than water and the temperature is 14 million degrees C.
During fusion, a tiny amount of the mass of the hydrogen atoms is converted into energy: Einstein’s famous equation, E = mc2.
The Sun is so large and dense, it takes 100,000 years for the energy in the core to get to the surface.

23. WHAT IS A BINARY STAR?
Not all stars are like our Sun, alone at the center of its own solar system.

24. WHAT IS A BINARY STAR?
Not all stars are like our Sun, alone at the center of its own solar system.
Some stars have a companion or partner.

25. WHAT IS A BINARY STAR?
Not all stars are like our Sun, alone at the center of its own solar system.
Some stars have a companion or partner.
When two stars orbit together around a common center of mass, this is known as a binary star.

26. WHAT IS A BINARY STAR?
Not all stars are like our Sun, alone at the center of its own solar system.
Some stars have a companion or partner.
When two stars orbit together around a common center of mass, this is known as a binary star.
As many as ½ of the stars in the Milky Way galaxy are binaries or multiple stars.
The closest star to our solar system, Alpha and Beta Centauri, is a binary star.

28. HOW DO WE KNOW HOW FAR AWAY A STAR IS?
Geometry can be used to calculate the distance to objects in the sky.

29. HOW DO WE KNOW HOW FAR AWAY A STAR IS?
Geometry can be used to calculate the distance to objects in the sky.
Parallax is a change in position of an object caused by change in position of the observer.

30. HOW DO WE KNOW HOW FAR AWAY A STAR IS?
Geometry can be used to calculate the distance to objects in the sky.
Parallax is a change in position of an object caused by change in position of the observer.
By measuring the parallax of an object, we can calculate the distance.

31. HOW DO WE KNOW HOW FAR AWAY A STAR IS?
Geometry can be used to calculate the distance to objects in the sky.
Parallax is a change in position of an object caused by change in position of the observer.
By measuring the parallax of an object, we can calculate the distance.
The closer an object is, the less the parallax.

32. HOW DO WE KNOW HOW FAR AWAY A STAR IS?
Geometry can be used to calculate the distance to objects in the sky.
Parallax is a change in position of an object caused by change in position of the observer.
By measuring the parallax of an object, we can calculate the distance.
The closer an object is, the less the parallax.
The farther away an object is, the greater the parallax.

34. WHAT ARE THE PROPERTIES OF STARS?
Apparent magnitude is how bright an object appears in the sky. Brightness changes with distance. The closer an object is, the brighter it will appear.

35. WHAT ARE THE PROPERTIES OF STARS?
Apparent magnitude is how bright an object appears in the sky. Brightness changes with distance. The closer an object is, the brighter it will appear.
Absolute magnitude is how bright an object would be if it were a standard distance away from Earth. Adjustments are made for the distance of an object to determine its actual brightness.

36. WHAT ARE THE PROPERTIES OF STARS?
Apparent magnitude is how bright an object appears in the sky. Brightness changes with distance. The closer an object is, the brighter it will appear.
Absolute magnitude is how bright an object would be if it were a standard distance away from Earth. Adjustments are made for the distance of an object to determine its actual brightness.
Luminosity is the measure of the energy output of a star. How hot a star is, what color is it? Hotter stars are blue. Cooler stars are red.

37. WHAT ARE THE PROPERTIES OF STARS?
Apparent magnitude is how bright an object appears in the sky. Brightness changes with distance. The closer an object is, the brighter it will appear.
Absolute magnitude is how bright an object would be if it were a standard distance away from Earth. Adjustments are made for the distance of an object to determine its actual brightness.
Luminosity is the measure of the energy output of a star. How hot a star is, what color is it? Hotter stars are blue. Cooler stars are red.
Classification – luminosity is used to classify stars. Stars are classified by how hot they are.

39. WHAT ARE ABSORPTION LINES?
Light coming from a star can be separated into a spectrum or rainbow with a spectrometer/spectroscope.

40. WHAT ARE ABSORPTION LINES?
Light coming from a star can be separated into a spectrum or rainbow with a spectrometer/spectroscope.
Some of the wavelengths of light are absorbed by elements in the star, leaving black lines in the spectrum.

41. WHAT ARE ABSORPTION LINES?
Light coming from a star can be separated into a spectrum or rainbow with a spectrometer/spectroscope.
Some of the wavelengths of light are absorbed by elements in the star, leaving black lines in the spectrum.
Each element absorbs different wavelengths of light.

42. WHAT ARE ABSORPTION LINES?
Light coming from a star can be separated into a spectrum or rainbow with a spectrometer/spectroscope.
Some of the wavelengths of light are absorbed by elements in the star, leaving black lines in the spectrum.
Each element absorbs different wavelengths of light.
By looking at the absorption lines, we can tell what elements are in a star.

43. NORMAL SPECTRUM
ABSORPTION LINE SPECTRUM

44. WHAT IS RED SHIFT?
If an object is moving, any waves emitted by the object become distorted by this motion.

45. WHAT IS RED SHIFT?
If an object is moving, any waves emitted by the object become distorted by this motion.
For sound waves, this is know as the Doppler Effect.

46. WHAT IS RED SHIFT?
If an object is moving, any waves emitted by the object become distorted by this motion.
For sound waves, this is know as the Doppler Effect.
For electromagnetic waves such as light, this is known as Red Shift or Blue Shift.

47. WHAT IS RED SHIFT?
If an object is moving, any waves emitted by the object become distorted by this motion.
For sound waves, this is know as the Doppler Effect.
For electromagnetic waves such as light, this is known as Red Shift or Blue Shift.
Red Shift – if an object is moving away from you, the absorption lines are shifted or moved toward the red end of the spectrum. Waves are stretched out.

48. WHAT IS RED SHIFT?
If an object is moving, any waves emitted by the object become distorted by this motion.
For sound waves, this is know as the Doppler Effect.
For electromagnetic waves such as light, this is known as Red Shift or Blue Shift.
Red Shift – if an object is moving away from you, the absorption lines are shifted or moved toward the red end of the spectrum. Waves are stretched out.
Blue Shift – object is moving toward you, absorption lines are shifted toward the blue end of spectrum. Waves are compressed.

53. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.

54. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).

55. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.

56. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.

57. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.
The star lives for billions of years as a main sequence star, until it runs out of hydrogen fuel in the core and can no longer push against gravity

58. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.
The star lives for billions of years as a main sequence star, until it runs out of hydrogen fuel in the core and can no longer push against gravity
Gravity wins and collapses the star.

59. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.
The star lives for billions of years as a main sequence star, until it runs out of hydrogen fuel in the core and can no longer push against gravity
Gravity wins and collapses the star.
The collapse creates heat and pressure which starts helium fusion, and the release of energy causes the star to swell up, become a red giant, and swallow the Earth.

60. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.
The star lives for billions of years as a main sequence star, until it runs out of hydrogen fuel in the core and can no longer push against gravity
Gravity wins and collapses the star.
The collapse creates heat and pressure which starts helium fusion, and the release of energy causes the star to swell up, become a red giant, and swallow the Earth.
Eventually, the star does not have enough heat and pressure to continue helium fusion.

61. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.
The star lives for billions of years as a main sequence star, until it runs out of hydrogen fuel in the core and can no longer push against gravity
Gravity wins and collapses the star.
The collapse creates heat and pressure which starts helium fusion, and the release of energy causes the star to swell up, become a red giant, and swallow the Earth.
Eventually, the star does not have enough heat and pressure to continue helium fusion.
Nuclear fusion stops, and the remaining gases are blown off as a planetary nebula.

62. LIFE CYCLES – STARS LIKE OUR SUN
Starts out as a nebula or cloud of gas.
Gravity collapses the cloud until a protostar forms (hot and spinning gas).
Gravity continues to build up heat and pressure in the protostar until hydrogen fusion begins – a main sequence star is born.
The energy from fusion pushes outward and creates equilibrium (balance) which keeps gravity from collapsing the star further.
The star lives for billions of years as a main sequence star, until it runs out of hydrogen fuel in the core and can no longer push against gravity
Gravity wins and collapses the star.
The collapse creates heat and pressure which starts helium fusion, and the release of energy causes the star to swell up, become a red giant, and swallow the Earth.
Eventually, the star does not have enough heat and pressure to continue helium fusion.
Nuclear fusion stops, and the remaining gases are blown off as a planetary nebula.
The star becomes a white dwarf, cooling off eventually into a black dwarf.

68. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.

69. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.
Blue, massive stars use their fuel much quicker and have shorter lives, only few million years.

70. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.
Blue, massive stars use their fuel much quicker and have shorter lives, only few million years.
Massive stars continue fusing elements up to iron on the periodic table as red supergiants.

71. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.
Blue, massive stars use their fuel much quicker and have shorter lives, only few million years.
Massive stars continue fusing elements up to iron on the periodic table, as red supergiants.
However, massive stars cannot fuse elements beyond iron, and fusion stops when the core fills with iron.

72. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.
Blue, massive stars use their fuel much quicker and have shorter lives, only few million years.
Massive stars continue fusing elements up to iron on the periodic table.
However, massive stars cannot fuse elements beyond iron, and fusion stops when the core fills with iron.
Gravity wins, star collapses until neutrons in the middle of the core stop the collapse (neutron degeneracy pressure).

73. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.
Blue, massive stars use their fuel much quicker and have shorter lives, only few million years.
Massive stars continue fusing elements up to iron on the periodic table, as red supergiants.
However, massive stars cannot fuse elements beyond iron, and fusion stops when the core fills with iron.
Gravity wins, star collapses until neutrons in the middle of the core stop the collapse (neutron degeneracy pressure).
Collapsing material bounces off the neutron core creating a supernova explosion.

74. LIFE CYCLES – STARS 10 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star.
Blue, massive stars use their fuel much quicker and have shorter lives, only few million years.
Massive stars continue fusing elements up to iron on the periodic table, as red supergiants.
However, massive stars cannot fuse elements beyond iron, and fusion stops when the core fills with iron.
Gravity wins, star collapses until neutrons in the middle of the core stop the collapse (neutron degeneracy pressure).
Collapsing material bounces off the neutron core creating a supernova explosion.
Neutron core remains behind as a neutron star.

75. LIFE CYCLES – STARS 20 TIMES MORE MASSIVE THAN OUR SUN
Life cycle starts the same: nebula, protostar, main sequence star, red supergiant.
Collapsing material bounces off the neutron core creating a supernova explosion.
Gravity finally wins, neutron core is crushed and collapses into a black hole.

76. WHAT IS A NEUTRON STAR?
After a star explodes in a supernova, the remainder may form a neutron star.
A neutron star is formed when gravity crushes all the remaining matter until the neutrons are packed as close together as possible without crashing into each other.
So dense that a teaspoon of neutron star weighs a billion tons.
A neutron star with the mass of the Sun would only be the size of Salt Lake City.

77. WHAT IS A BLACK HOLE?
The remains of the most massive stars, more than 20 times the mass of our Sun, collapse into black holes.

78. WHAT IS A BLACK HOLE?
The remains of the most massive stars, more than 20 times the mass of our Sun, collapse into black holes.
A black hole is a place where matter has collapsed into an infinitely dense point.

79. WHAT IS A BLACK HOLE?
The remains of the most massive stars, more than 20 times the mass of our Sun, collapse into black holes.
A black hole is a place where matter has collapsed into an infinitely dense point.
Gravity inside a black hole is so strong that nothing can escape, not even light.

81. HOW ARE ELEMENTS MADE IN STARS?
The universe began with only hydrogen and some helium. Where did all the other elements come from?

82. HOW ARE ELEMENTS MADE IN STARS?
The universe began with only hydrogen and some helium. Where did all the other elements come from?
Fusion – stars fuse hydrogen in their cores into elements up to iron on the periodic table.

83. HOW ARE ELEMENTS MADE IN STARS?
The universe began with only hydrogen and some helium. Where did all the other elements come from?
Fusion – stars fuse hydrogen into elements up to iron on the periodic table.
All elements heavier than iron are formed in supernova explosions.

84. HOW ARE ELEMENTS MADE IN STARS?
The universe began with only hydrogen and some helium. Where did all the other elements come from?
Fusion – stars fuse hydrogen into elements up to iron on the periodic table.
All elements heavier than iron are formed in supernova explosions.
We are made of dead stars.