Astronomy Flashcards
What is astronomy?
A branch of science that deals with space and the whole universe
What is an astronomical unit?
A unit of measurement (au) to measure the distance from the sun
What is a light year?
A unit used to measure the distance that light travels in one year (measures the distance from the sun)
Why is it said that if we look into the sky, we’re looking to the past?
Because it could take a star hundreds of light years to reach us and when it arrives, it is long dead.
What are galaxies?
A system of millions & billions of stars of which our solar system is part of.
What galaxy do we live in?
We live in the Milky Way.
What are to different shapes of galaxies?
Spiral, elliptical, lenticular, & irregular.
What type of shape does our galaxy have?
Our galaxy (Milky Way) is a spiral
What is our galaxy centered around?
The galactic bulge and suppermasive black hole
Star phase life cycle:
- Huge clouds of dust and gas collapse by gravitational force and create a protostar
- The young stars continue to collapse
- Stars expand as they grow older
- When core runs out of hydrogen & helium the stars become less bright
What will happen to the sun?
In about 5 billion years, the sun will expand & the core will run it if hydrogen and helium & it will become less bright & later become a red giant star
Order of the planets
Sun, Mercury, Venus, earth, Mars, (asteroid belt) Jupiter, Saturn, Uranus, Neptune, (asteroid belt)
Why is Uranus and it’s likes special?
It’s special bc the axis rotation is tilted sideways, so it’s north and south likes lie where most other planets have their Equators.
Pluto is considered a dwarf planet and not an actually planet bc..
it is too small and there are other objects orbiting the wary that are the same size, so if Pluto was considered a planet, they would be too.
Layers of the sun:
Inner core, radiative zone, convection zone, photosphere, chromosphere, corona (“haze”)
Core:
High pressure temp & high reactions occur
Radiative zone:
A very dense layer . Radiation including light is absorbed and re - admitted
Convection zone:
There is constant circulation of plasma from hot to cooler regions
Photosphere:
The yellow part of the sun that can be seen
Chromosphere:
The red coloured layer that can only be seen during a solar eclipse
Corona “haze”:
Hot outer layer about 1 million degrees
Nuclear fusion:
The process that fuels or sun. Allows it to give off energy calls nuclear fusion. To atomic buckle dude together to create a larger nucleus and release energy in nuclear fusion
What does the sun burn on?
Hydrogen and helium
Rotation:
The planets individual spinning around an internal axis
Revolution:
All the planets moving around the sun.
Lunar eclipse:
An eclipse where the moon appears darker as it passes into earths shadow
Solar eclipse:
A type of eclipse when the moon passes between the sun and the earth and the moon blocks the sun. (new moon only)
Difference between low orbiting and high orbiting satellite
A low orbiting satellite orbits around the earth between 160 and 2000 km while a high orbiting satellite and the high orbiting one orbits above earth
What are craters?
Craters are cavities usually found in the moon or earth
How are craters caused?
By the impact of a meteoroid
What is a meteor?
A tail of light that appears in the night sky when a meteorite enters the atmosphere
What is a meterorite?
A piece of rock that enters the earths atmosphere from space..
Why are there more meteors recorded than meteorites?
?
Why does the moon have more craters than the earth?
Because earth has an atmosphere which causes asteroids to burn up before they reach the surface. Therefore the moon does not.
What effects does space travel have on human bodies
Space sickness, weightlessness, muscular atrophy, body fluid imbalance
The Big Bang:
The rapid expansion of matter that according to theories marked the origin of the universe
Some evidence of the Big Bang
The universe is expanding, the abundance of different elements in the universe and the “cosmic microwave”
