Chapter 8 Astonomy Flashcards
A nebula
Is a vast cloud of gas and dust that may be the bit to place of stars and planets.
Neutron star
Is a star so dense that only neutrons exist can at its core
Nuclear fusion
Is the processor of energy production in which hydrogen nuclei combine to from helium nuclei. This is a nuclear reaction.
Protostar
Is a dense, hot, condensed object at the center of a nebula.
Luminosity
Is a start total energy output per second; its power in joules per second, (J/s).
The solar nebula theory (1)
The theory describes how stars and planets form by contractions of spinning disks of gas and dust. Planet and stars form together.
Solar wind
Is a stream of fast-moving charged particles ejected by the sun into the solar system.
Star
A star is a celestial body made of hot gases, mainly hydrogen and helium.
White dwarf
Is a small, dim, hot star.
Supernova
Is a massive explosion in which the entire outer portion of a star is blown off.
Black hole formation
Black holes are formed if the helium core of a star survives its death.
Necessary components for nuclear fusion to begin
- really hot
- core gets denser
- lots of pressure
- compression
Who was one of the first to turn the telescope to the sky.
Galileo
What are optical telescopes?
And optical telescope detects visible light
Refracting telescope
A telescope that uses a lens to collect the light form an object.
Reflecting telescope
A telescope that uses mirrors to collect the light form an object.
Satellites uses
- weather
- internet
- radio
- GPS
- land surfaces
- oceans and rivers
Geosynchronous satellites
Are satellites that take 24 hours to orbit the earth and since the earth is turning in the same direction the satellite is turning it appears to always be on the same spot.
Beginning of protostar
Gravity can set the gas and dust particles into a spinning mottling around the core
Solar nebula theory (2)
The nebula (protostar) begins to contract and little lumps start forming bigger lumps called planetesimals.
Our sun: the structure
- The core
- The photosphere
- The Corona
Our sun: features
- Sunspots
- Solar flares
- Solar prominence
Chromosphere
The inner atmosphere of the sun
The core
- where nuclear fusion happens
- temperatures from 15 million degrees (C)
- a lot of pressure
Corona
- the hot outer part of the sun
- temperature: 1 million degrees
Moving gases
Where temperature and pressure increase
The photosphere
- called the surface of the sun (not solid)
- churning gases
- temperature: 5500 degrees
- where cooler sunspots occur
Solar flares
- they travel extremely fast & last only a few minutes
- travel from the chromosphere & through the corona
Solar prominence
- can last for days or weeks & go up to 400 000 km high
- large sheets of glowing gases going outward form the chromosphere
Sun spots
Huge darker & cooler areas in the suns photosphere
Evidence of rotating sun
- it take 27 days for 1 rotation
- 35 days for the sun spots to do 1 full rotation
- it does not rotate as a solid body
The importance of the sun
- heat / warmth
- basis of photosynthesis
- light
- needed for all life on earth
What radiation does the sun emit
- Microwaves
- Gamma rays
- X rays
- Radio waves
- Light waves
20%
Of solar radiation is absorbed by earths atmosphere
30%
Of solar radiation is reflected by earths atmosphere ( clouds, surface and oceans )
50%
Of solar radiation is absorbed but the earths surface and oceans
Hertzsprung-Russel diagram
Shows the properties of stars, star color, temperatures and luminosity.
90%
Of stars are in the main sequence
10%
Of know stars are not in the main sequence
Low mass stars
- generally red dwarfs
- have less mass then our sun
- consumes its helium very slowly
- life span is 100 billion years
- will turn into faint white dwarf
- maybe come black dwarf
Intermediate mass stars
- our sun!
- life span is 10 billion years
- when all the hydrogen is used up core will collapse
- temp will rise and the sun will expand, fitting to mars ring orbit
- eventually will become a small hot dim white dwarf
High mass stars
- 12 or more solar masses than our sun
- die faster and more violently
- a supernova will occur
- will become red giant, then cool
- helium core maybe become black hole or neutron star
Neutron stars
- so much pressure only neutrons can exist
- strong magnetic field
- rotate very fast
- incredible hot
Black holes
- tiny patch of space
- massive amount of mass and gravity
- nothing can escape it
Electromagnetic radiation
Radiation consisting of electromagnetic waves that travel at the speed of light
Absolute magnitude
The magnitude of a star they would observe if placed 32.6 lift years from earth
Spectroscope
An optical instrument they produced a spectrum form a narrow beam of light and projects it onto a photographic plate or digital detector
Spectral lines
Specific wave lengths within a spectrum if characterized lines
The main sequence
A narrow band of star in the H-R diagram
