Space - Topic 2 Flashcards
(49 cards)
What method was used in the past before navigation tools were invented?
They would use their naked eyes to observe space leading to very limited knowledge
What were quadrants?
Navigational instruments in the shape of a quarter circle used for measuring altitudes of astronomical objects
What were sextants?
Navigational instruments similar to quadrants but in the shape of a sixth of a circle they where used for measuring the position of stars
What are the disadvantages of optical telescopes?
They can only be used at night
They cannot be used if the weather is poor or cloudy
What are the advantages do radio telescopes have over optical?
They can be used in daytime as well as night
Hey can be used in bad weather because their radio waves are not blocked by clouds
How does a radio telescope work?
First Weak radio waves from space are reflected by a large curved reflector which brings the waves to a focus at the antenna
At this point the weak radio waves combine to give a strong signal at the antenna
The reflector should be as big as possible so that the many weak radio waves are collected giving as strong a signal as possible
What does the diagram of a radio telescope have?
A curved reflector (dish) reflecting the waves
A focus in the middle focusing on the waves (the centre)
The antenna marking the connection stronger (box)
Radio waves being collected and going into the dish
What are the advantages of space telescopes?
They can observe the whole sky
They operate in day and at night
Wha are the disadvantages of space telescopes?
They are expensive to launch
They are difficult to maintain and if anything goes wrong only astronauts can fix them
What is a space probe?
A probe is an unmanned spacecraft that travels through space to collect information
What are space robots?
NASA space robots are robotic devices used to aid augment or substitute for astronauts in order to perform difficult or routine tasks
What is an AU?
An AU is an astronomical unit
What is 1 AU defined as
1 AU is defined as the distance between the earth and the sun
What is 1 AU in meters (standard form)?
1AU is 1.5 x 10¹¹ meters
What is a light year?
A light year (ly) is the distance that light travels in 1 year
(IT IS NOT A TIME)
What is one light year the equivalent to in meters?
One light year is the equivalent of 9.46 x 10¹⁵ meters
What is the formula for distance, velocity and time?
d = vt
What is the Big Bang theory?
The Big Bang theory is an effect to explain what happened at the very beggining of this universe
It suggest that there was a ‘big bang’ and the universe was formed and that there universe continues to expand to this day
What happened in the Big Bang?
The universe is thought to have started at an infinitely small, hot and dense singularity.
The universe inflated, expanded and cooled, going from very small to very hot to the size and temperature it is today
What evidence is there for the Big Bang theory?
Expanding universe and galaxy’s moving away from each other. It implies a starting point.
A radiation detected evenly across space spread after the Big Bang called cosmic microwave background radiation
An abundance of light elements like hydrogen and helium has produced at the time of the Big Bang
What is the age of the universe?
13.8 billion (or 13.8 x 10⁹) years
What is the moon?
The moon is the satellite of the earth
Not that important:
It was formed billions of years ago when the earth collided with its twin planet, Theia. It’s held in orbit around the earth by the earth gravitational pull and takes one month (and 27 days) to complete its orbit.
Why can we see the moon at night?
The light from the sun is reflecting through it (/the moon reflects the light from the sun) making it so it shines
Why is the moon Important for life on earth?
It stables the climate,
Helps keep earths axis the same,
It helps us balance and stay in a cycle of sun equally around the world,
Life couldn’t exist if the moon weren’t there,
It prevents the earth from wobbling on its axis stopping the sun being on one side for half a year and then switching
