SCIENCE 9: Constellations Flashcards
NOT A QUESTION:
How many minutes does it take for sun’s light to reach Earth?
The Sun is is only about 150 million kilometers away and it takes only 8 minutes and 20 seconds for sunlight to reach Earth.
It is a natural luminous body visible in the night sky, especially at night. It is a huge sphere of very hot glowing gas.
Star
What are the 5 Basic Characteristics of a Star?
- Brightness
- Color
- Surface Temperature
- Size
- Mass
Is the brightness the star would have if all stars were the same distance from Earth.
Absolute Brightness
Large stars shines brighter than small stars.
Hot stars shines brighter than cool stars.
Brightness by Size and Temperature
The color of the star indicates its surface temperature.
Color and Temperature:
- Red > Orange > Yellow > White > Blue
Stars that are about the size of the Earth.
White Dwarf
Stars have a life cycle that depends on the initial mass of star.
Mass:
- Low-mass stars survive longer than massive stars
- Low-mass stars usually end up as white dwarf stars while massive stars as neutron stars or black holes
The more massive a star is, the hotter its surface.
Surface Temperature
A star’s apparent brightness is the brightness you see from Earth.
Brightness by Distance:
- A hot, large star that is VERY FAR FROM EARTH does not look very bright
- The closer the star, the brighter
Are a group of stars, which form a pattern when seen from Earth.
Constellation
Why do some constellations appear and disappear in the night sky throughout the year?
Due to the REVOLUTION of the Earth
Why do some constellations appears to move across in the night sky from east to west?
Because of Earth’s ROTATION on its axis from west to east
How many constellations are recognized by the International Astronomy Union (IAU)?
88 Constellations
