enhanced science module 7-8

• Star

  Is a type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity
• The more massive the star, the faster it burns up its fuel supply and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion.
• COLOR

  The color of a star depends on its surface temperature. Hotter stars’ appearance are blue, whereas cooler stars appear to have orange or red hues.
• BRIGHTNESS

  Their brightness is a factor of how

  much energy they emit, known as luminosity. A star’s apparent magnitude is its perceived brightness, factoring in size and distance, while its total magnitude is its true

  brightness irrespective of its distance from Earth.
• SIZE

  Neutron stars can be just 20 to 40 km in diameter, whereas a white dwarf is almost similar to the Earth’s size. The largest super giants, on the other hand, can be more than 1500 times larger than our sun.
• MASS

  Low mass stars/ small stars survive for billions of years; they die quietly and in their place, a small white dwarf is left behind. high mass stars/large stars survive for a few million years; die in a supernova explosion and in their place, a blackhole is left behind.
• The brightness of a star as seen from the Earth depends on two factors – distance and actual brightness (or absolute brightness) of the star. The star’s brightness as seen from Earth is its apparent brightness.
• Constellations

  Imaginary group of stars
• The Sun is only about 150 kilometers away and it takes only 8 minutes and 20 seconds for sunlight to reach our world.
• Absolute brightness

  the brightness of a star would have if all stars were the same distance from earth
• Apparent brightness

  brightness you see from earth
• Scientists believe that all stars came from hue clouds of gas and dust called nebulae.
• Many of the constellations have names that can be traced back to early babylonians and greek civilizations.
• The stars that make up a constellation appear close to each other from Earth, but are actually very far apart.
• ORION: THE HUNTER

  The Greeks called Orion, the Hunter because it is prominent in the night sky all over the world during winter. In Filipinos, Orion's belt, the three stars, mean tres marias.

  
• Taurus: The Bull

  Visible during summer in the Philippines.

  
• The revolution is responsible for the fact that we can see different parts of the sky at different parts of the year.
• There are 88 constellations recognized by the International Astronomical Union (IAU).
• Some constellations appear and disappear in the night sky throughout the year due to the revolution of the Earth.
• The constellations appears to move across night sky from east to west.
• Scorpius: The Scorpion

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• Virgo: The Maiden

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• Pegasus: The Winged Horse

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• Gemini

  Twins

  
• Aries

  Aries

  
• Capricornus

  
• Leo

  
• Cancer

  
• PERSEUS

  
• BIG DIPPER

  
• DRACO

  
• SOUTHERN CROSS

  
• URSA MAJOR

  
• CASSIOPEIA

  
• HERCULES

  
• ANDROMEDA