Topic 3 - Waves And The Universe Flashcards
What do all planets orbit around?
Stars
What is the smallest planet in our solar system
Mercury
What is the biggest planet in our solar system
Jupiter
Which planet is furthest from the sun?
Neptune
What Galaxy are we in?
Milky Way
What types of waves do SETI use to look for life?
They monitor radio signals from other planets. They also send radio waves into space for any other life forms to detect.
What is a disadvantage of using radio waves to look for life?
Giant stars and other things also produce radio waves
Which planets and moons are scientist looking at for signs of life?
Mars and Titan (saturn’s largest moon)
What things do the probes record?
Conditions on the planet/moon e.g. Temperature
Some collect rock samples and take photos.
How did earth know what the probes found?
The probes would send radio signals back to earth about the data they have found.
What are the problems with earth telescopes?
The earths atmosphere absorbs a lot of the light coming from space.
Light pollution means you can’t see dull objects in the sky.
What do telescopes use to observe the universe?
EM waves
Which type of telescope are good for seeing high temperature events in space?
X-Ray telescope
Which type of telescope was responsible for the discovery of the cosmic microwave background radiation?
Radio telescopes
Which EM waves do telescopes use?
All
How has studying the stars become easier?
Better and bigger telescopes so better resolution and we can see things further away because it collects more light.
Computers store all the data which makes it easier to collect and analyse.
We can send telescopes into space and use the whole EM spectrum
What is a spectrometer
Tool used to analyse the light given out by stars and galaxies
What are the dark lines in the light spectra from galaxies and star?
They are caused by the light at those wavelengths being absorbed e.g. By elements In the star atmosphere
What can absorption spectra help work out?
What the stars and galaxies are made from. Each element has its own particular absorption spectrum
Why are the bright lines produced from stars/galaxies called?
Emission spectra
What is the Doppler effect?
This is when a fast moving object goes past as and the pitch of the noise or the colour of the object changes. This is because as the object moves it squashes and stretches the waves its producing so as its moving towards us the wavelength is shorter so the object has a higher pitch or looks blue. As the object is moving away from us the waves are stretched so the wavelength is longer meaning the object has a lower pitch or appears red.
Describe the lifecycle of a star.
cloud of dust and as called NEBULA collapses due to gravity to for a PROTOSTAR
GPE gets turned into nuclear engird as protostar undergoes thermonuclear fusion and turns into MAIN SEQUENCE STAR
enters stable period where force of gravity = force of fusion
fuel (hydrogen) runs out, it cools and swells to form RED GIANT
small stars then eject outer layers (PLANETARY NEBULA) to form a WHITE DWARF which disappears over time
big stars explode to form SUPERNOVA which then throws out outer layers to form NEUTRON STAR or bigger stars form BLACK HOLE.
What is the steady state theory?
It says that the universe has always been here. It also says that as the universe expands new matter is created so it always looks the same.
Are galaxies moving away or towards us and how do you know?
They are moving away because they have all been redshifted
What is the Big Bang theory
It says that at some point in time the universe must have been compressed into a very small space. This then exploded and it started expanding. This expansion is still going and we can use this to estimate that the Big Bang happened about 14 billion years ago.
What is uniform microwave radiation (CMB radiation)
It is the low frequency electromagnetic radiation that is coming from all parts of the universe. It is mainly in the microwave part of the EM spectrum.
State a piece of evidence that supports the steady state theory and the Big Bang theory.
Redshift
State a piece of evidence that only supports the Big Bang theory
cosmic microwave background radiation
