How stars form
Where do stars form from?
An accumulation of dust and gas.
How do death of the stars happen?
The star becomes cooler because of the lack of hydrogen.
What happen with the leftovers of a star that dies?
Is used to create planets and other objects that orbit the central star.
What is the first step of the process of the death of a high mass star?
The core starts contracting and increases in density and temperature.
How do astronomers classify stars?
By their color, size, and brightness
How many years it takes to form a star?
About a milion
How can we know the stars age?
With its color, as more energy is created, younger is tyhe star.
What is left behind from a red giant?
Planetary nebula
What is the result of the outer layers of the star collapsing?
It results in a supernova
How is it called the brightness of a star as it appears from the Earth?
Apparent brightness
What is nebula?
A cloud of gas an particles
Where can we find the oldest stars in the galaxy?
The oldest stars are the closest to the sun.
Which is the last stage of the death of a star?
A black dwarf
What is left behind from supernova?
A black hole or a neutron star.
How is it called to how a star really is?
Absolute brightness
What is the next stage, after the nebula is formed?
It becomes a protostar.
How do scientists calculate the exact age of a star?
How big is a white dwarf?
The same size as the Earth
How long does it take for a star to die?
Milions of years
What characteristic indicates their temperature?
The color
What are three layers of a star?
Core, mantle, and atmosphera
Which percentge of their life do they spend on the main sequence?
About 90%
How long does a star live?
Depends on its mass
What happens after the planetary nebula?
It converts to a white dwarf
Which two components make most of the mass of a star?
Hydrogen and helium