Science: Brightness of Stars and the Solar System Flashcards
What is a star?
A huge ball of very hot matter that gives off energy
What does apparent mean?
The way something looks
What is a solar system?
A system of 8 planets and the sun, along with moons, asteroids and comets
Is the sun a star?
Yes. It’s the only star in our galaxy, the Milky Way, and is at the center of the galaxy.
Why do stars shine?
Processes in stars produce huge amounts of energy.
True or false: the temperature of our sun is around 15,000,000 (C) or 27,000,000 (F)
True
What percentage of our solar system’s mass does the sun make up?
99%
what are the main layers of the sun?
The core - where the sun’s energy is generated. The radiative and convection zones carry that energy to the sun’s surface.
What are the 3 layers of the sun’s atmosphere?
Photosphere, chromosphere and the corona.
When do solar flares occur?
When energy heats the sun so much that it causes particles to explode into outer space.
What is a light year?
It is a unit of measurement used to measure the enormous distance between stars.
One light year = how far light travels in one year, which is 9,460,800,000,000 kilometers.
True or false: the closest star from Earth is 4.2 light years away.
True!
Why do stars appear so small, even when they are bigger than our planet?
They appear small because they are so far away from Earth.
What factors determine how bright a star appears to us on Earth?
- Distance
- Size
- Temperature
Where are the closest stars to our solar system located?
The Alpha Centauri star system
What do scientist believe is the key ingredient to support life?
Water
What are 3 characteristics of our sun?
It is very hot, at 15,000,000 degrees (C)
Its is very large: it is the largest object in our solar system
Its is very heavy: it makes up more than 99% of the mass of our solar system
What is the Kelvin Scale?
Kelvin is the actual metric unit of temperature
Stellar classification: what color is the coolest? And the hottest?
Coolest is purple/gray/black, at less than 700K
Hottest is blue, at more than 30,000K
What are the 7 stages of the sun’s lifecycle?
- Molecular cloud
- Open cluster
- Low mass sun
- Red giant
- Planetary nebula
- White dwarf
- Black dwarf
What is AU and what does it measure?
Astronomical Unit measures the distance between Earth and Sun
What does Parsec measure?
It measures the distance to astronomical objects outside of the solar system
What is Absolute Magnitude
A unitless value of how luminous (bright) an object in space would appear if viewed from 10 parsecs away
What is Apparent Magnitude?
A unitless value of how luminous an object in space appears from Earth
