Space Flashcards
Why do we have seasons
Because earth is on a tilt, when the earths axis point is pointed towards the sun it is warmer (summer) ad when it is pointed away from the sun it is colder (winter)
What is the cause of a full moon
When the earth in in between the moon and the sun
Why dosent the arctic circle get sunlight some days of the year
Because the northern hemisphere is tilted away from the sun so sunlight doesn’t reach the arctic circle
How does a lunar eclipse occur
Earth comes between the sun and the moon, blocking the sunlight falling on the moon
How does a solar eclipse occur
The moon is between the sun and the earth blocking the suns light from reaching us causing a shadow to cast onto earth
If you were on the moon during a total lunar eclipse what would you see
You would see a solar eclipse, it is always opposite
What Keeps the moon orbiting the earth
Gravity attracts the moon to the earth but because the moon is constantly moving it doesn’t fall down
What causes tides on earth
The moon is pulling on us we pul back on the moon causing the water to bulge up and cause high and low tides
How long does it take for earth to make a full rotation
24 hours
What is gravity
All objects with mass are attracted to other things with mass
What has gravity done
Formed planets, made planets round, keeps planets in orbit around the sun, gave the solar system its shape, creates stars, keeps some planets warm
Why is earths atmosphere special
Keeps us warm by heat being by air particles and heating up the atmosphere, protects us from cosmic rays, protects us from meteors by burning them up before they hit earth
What is the Big Bang theory
- There was a hot ball of matter tinier than an atom
- Big Bang occurred energy spread outward vey quickly
- The universe cooled, energy began to turn into matter
- Over millions of years the matter formed into clumps leading to stars and galaxies
Why does the earth have a molten core
Friction from the molten core spinning inside creates friction (heat) the keeps the core warm
Why is earths rotation special
Moving molten metals inside creates magnetic fields around us, fiction causes the earth to slow down, determines length of daylight
How was our solar system created
- cloud of dust forms from the Big Bang
- gravity pulls dust
particles together
-as dust collided core
heats up
-nuclear fusion occurs hydrogen collide to form helium
-solar wind pushes lighter particles outwards and the dense particles stay closer to the sun
Why are the terrestrial planets formed near the sun and the gas planets formed farther from the sun.
During the solar nebula the lighter gases were pushed into the outer wheel where the temperatures are lower and the didnt receive enough heat or energy to form a solid surface where as the terrestrial planets on the inner shell are closer to the sun so they formed solid, dense rocky surfaces.
What ways do stars change their physical properties
Because of nuclear fusion there will be changes in their temperature, luminosity, size and colour
What determines wether a star will become a black hole at the end of its life cycle.
The size of the star. The star must be a massive star in order to possibly end up as a black hole
Will the sun form a black hole
No it will not because the sun isn’t a massive star and it follows a different star lifecycle
Where do main sequence stars on the H R diagram get their energy from
Their energy source is nuclear fusion. The Rate they do this at depends on the mass of the star.
How do stars form
They began in a nebula, gravity pulls particles together over million of years, a protostar forms, gravity pulls in so much matter that core temperature reaches 15 mill degrees celsius, nuclear fusion begins
What is nuclear fusion
In the core of a star, hydrogen atoms fuse to form helium atoms and release large amounts of energy
2 important things about main sequence stars
- The higher the temperature and more luminous, the more massive the star is
- The lower the temperature and less luminous, the less massive the star is
What are the 2 lifecycles of stars
- Protostar,sun-like star (main sequence), red giant, planetary nebula, white dwarf
- Protostar, massive star, red supergiant, supernova, neutron star OR black hole
