Stars and Constellations

• There are approximately 400 Billions of stars and 170 Millions of galaxies
• Star


  A natural luminous body visible in the sky, especially at night
• Star


  • A huge sphere of a very hot glowing gas
  • The most widely recognized astronomical objects
  • Represents the most fundamental building blocks of galaxies
• Scientists believe that all stars came from huge clouds of gas and dust called nebulae
• Sun


  • A star
  • 150M km away from Earth and takes 8 mins and 20 seconds for sunlight to reach us
  • Closest star to earth
  • Medium-sized star with a diameter of 1.39M km (110 times that of Earth)
  • Lifespan of about 10B years
• Thermonuclear fusion in the sun

  Hydrogen is converted to helium and energy
• For 4.5B years the sun has been producing large quantities of energy per second
• The sun has 400 trillion watts of luminosity
• Proxima Centauri


  • Next closest star to Earth
  • 40 trillion km away or 4.24 light-years away
• Earendel


  • Detected in 2022 by the James Webb Space Telescope
  • 28 billion light-years away
• Composition of stars


  • Hydrogen (74%)
  • Helium (24%)
  • Traces of oxygen, neon, carbon, and nitrogen (2%)
• Brightness of stars


  • Depends on size and distance from Earth
  • Described in terms of magnitude and luminosity
• Magnitude of stars


  • Magnitude 1 stars are the brightest
  • Magnitude 6 stars are the faintest
  • Magnitude 3 stars are 2.5 times brighter than magnitude 4 stars
• Luminosity


  • Describes the rate at which a star radiates energy
  • Affected by size and surface temperature
  • The luminosity of the sun is used as the standard to describe the luminosity of other stars
• Alpha Centauri is 1.3 times as luminous as the sun
• Apparent brightness


  The brightness you see from the Earth
• Absolute brightness


  The brightness the star would have if all stars were the same distance from Earth
• A hot large star that is very far away from the earth does not look very bright
• Color and temperature of stars

  • The color of the star indicates its surface temperature
  • The more massive a star is, the hotter its surface
• Star sizes


  • Dwarf stars (70-80% the size of the sun)
  • Giant stars (2-10 times larger than the sun)
  • Super Giant Stars (more than 10 times the size of the sun)
• The life cycle of a star depends on the initial mass of the star
• There are 88 constellations recognized by the International Astronomy Union (IAU)
• The revolution is responsible that we can see different parts of the sky at different parts of the year
• Edmond Halley discovered that stars move and change positions, but since they are far away, their movement through space is not observed
• The stars seem to move as a cluster
• Circumpolar constellations in the Northern Hemisphere

  • Ursa Major
  • Ursa Minor
  • Cassiopeia
  • Cygnus
• Asterism


  Recognized group of stars within a constellation or shared between several constellations
• Constellations in the Southern Hemisphere

  • Crux or Southern Cross
  • Catrina
  • Centaurus
• Changing positions of constellations

  1. Earth's rotation around its axis

  2. Earth's revolution around the sun
• Constellations have names traced back to early Babylonian and Greek civilizations
• During summer in the Philippines the constellations of Orion and Taurus are not visible at night
• Beliefs and practices related to stars

  • The sky was considered a "window to the future"
  • The celestial body known as the "Morning Star" has been proved to be the planet Venus
  • Shooting stars or falling stars were thought to be stars falling from the sky, but now we know that they are actually meteors
• Astrology


  Pseudoscience that determines the influence of the state of the stars and the planets at the time of one's birth to an individual's destiny or future
• Astronomy


  Science that uses the principles of physics and mathematics to study the sky
• Beliefs about falling stars

  • Souls of poor people, drunkenly walking home after they had dinner at a rich star (Ancient Greece)
  • Fallen angels and demons (Early Jews and Christians)
  • Larrpan, a canoe that takes the deceased to the spirit-land in the sky called Baralku (Yolngum indigenous group in Australia)
  • Wishing on shooting stars
• KOKOLOGY


  Self Discovery!
• KOKOLOGY - Self Discovery! Activity

  1. Imagine there are horribly threatening monsters angrily rampaging the city

  2. What do you think is the cause of their anger; why the monsters are so furious?

  3. They're hungry and looking for food

  4. They're looking for their lost love

  5. Just because they are ugly monsters with high temper

  6. They're angry with this desperate world
• KOKOLOGY - Self Discovery! Activity


  1. You are walking in the art gallery. You are relaxed and stop at one picture. You stop and stare at this picture for a long time, amazed and fascinated. What kind of picture is that?

  2. Self-portrait

  3. Parody version of something

  4. Abstract

  5. Painting of nature
• KOKOLOGY - Self Discovery! Activity

  1. If you have a magical eraser that can erase anything, what will you do?

  2. Erase yourself

  3. Erase your lover

  4. Erase the third party
• KOKOLOGY - Self Discovery! Activity

  1. Again, you are in the art gallery, the same one as before. While you are looking at that picture, a guy standing next to you is about to say something. What is that might be?

  2. "What a beautiful painting, you think?"

  3. "How do you like this painting?"

  4. "Excuse me; do you know what time is it now?"

  5. "You know, I'm the one who painted this picture"