E01 Earth and Space Flashcards
(19 cards)
What does the Big Bang Theory state about the universe
That all matter began in an extremely hot, dense ‘singularity’ that has expanded and become less dense and cooler as a result
What does the Steady State Theory state about the universe
That the universe has no beginning or end and constantly creates matter to maintain the same density
What is Hubble’s law?
That galaxies are moving away from each other at speeds proportional to their distance
ie,
The further a galaxy is from earth, the faster it is moving away
What is the Doppler Effect?
The perceived change of frequency by an observer as an object moves closer or away
Longer wavelengths as an object moves away, and shorter as they come closer
How does the Doppler Effect explain the expanding universe?
Light observed from distant galaxies changes frequency depending on their motion relative to Earth. If they are moving away, their frequency is stretched toward the red end of the color spectrum. Scientists have noticed from Earth that galaxies tend to be red shifted, which suggests that they are in fact, moving away as the universe expands and creates more empty space between them and Earth.
What are the 3 proposed fates of the universe and what they entail
The Big Rip
The universe will expand so much it overcomes gravity and will rip itself apart, ending time itself
The Big Chill
All stars will eventually run out of energy and planets will freeze. The universe will become scattered particles that will never have the energy to meet again
The Big Crunch
The expansion of the universe will become unable to defy gravity, and the universe will fall back into another singularity. It also suggests that this singularity could have another ‘Big Bang’ and begin to expand again in a never-ending cycle
What is the life cycle of a star that is the same size or smaller than the sun
Nebula ➡️ Protostar ➡️ Main Sequence Star ➡️ Red Giant ➡️ Planetary Nebula ➡️ White Dwarf ➡️ Black Dwarf
What is the life cycle of a star that is 8 times larger than the sun
Nebula ➡️ Protostar ➡️ Main Sequence Star ➡️ Red SUPER Giant Nebula ➡️ Supernova ➡️ Neutron Star OR (If way denser) Black Hole
How are H-R diagrams set out? What patterns can you see on them?
Hertzsprung-Russel diagrams show the surface temperature in kelvin of stars graphed against the amount of energy emitted (luminosity). You can see where the different stages of the life of stars is based on their location on the graph
What is Apparent and Absolute magnitude and how are they different?
Apparent magnitude is the perceived brightness of a star from Earth, which makes closer stars appear brighter and vice versa, while Absolute magnitude provides a more accurate representation of brightness if all stars were to be the same distance from Earth. The lower the number on both, the brighter the star is
What are the 4 biophysical spheres of Earth?
Biosphere, Hydrosphere, Lithosphere and Atmosphere
Think about the nitrogen cycle (can’t import images lol)
Refer to diagram in book
Think about the carbon cycle (can’t import images lol)
Refer to diagram in book
What does the Ozone layer do?
Fully blocks UV-C and partially blocks UV-B that is harmful to humans
What is leading to the thinning of the Ozone?
CFC’s
What are the impacts of a thinning Ozone layer?
For humans - Increased risk of skin cancer and eye damage and premature aging
For ecosystems - Damaged plankton, plant growth and animals
What is the Montreal protocol and some of its impacts?
An agreement between countries to phase out the use of CFCs. It has allowed for the Ozone layer to heal and prevented ailments that would have arisen from its depletion
What are some solutions to slowing/stopping the enhanced greenhouse gas effect/global warming?
Reduce burning of fossil fuels and increase reliance on renewable energy and energy efficient manufacturing and appliances, reforestation, use of public transportation
What is some evidence for global warming?
Rising sea levels, acidity and temperatures
Increased atmospheric temperatures
Changing weather patterns and increased intensity/frequency of natural disasters
