Past Papers Flashcards
Describe the Giant Impact Theory.
Mars size object collides with Earth
Cores merge and splash material forms Moon.
What evidence from the Apollo programme supports the Giant Impact Theory? Give two.
Lunar rocks show similar oxygen content to those found on Earth.
Suggestion that a large part of the Moon was once molten.
Lunar crust is mainly anorthosite.
Define ‘Potentially Hazardous Objects’
Objects that come relatively close to Earth so that there is a chance of a collision.
Why is it important to monitor PHOs?
To predict object trajectory, project damage etc.
What is Heliocentric Parallax?
Thumb in front of eyes!
How do we use Cepheid Variables to measure distances?
They have a period-luminosity relation. From this we can work out the absolute magnitude, and therefore the distance!
Where are White Dwarfs on the HR Diagram?
Towards the bottom-left
Where are Red Giants on the HR Diagram?
Towards the top-right.
Describe how we can use Pegasus for finding other objects in the night sky.
If you use the bottom right and top left stars of the square you can use a line to find the Andromeda Galaxy.
Using the top right and bottom right stars of the square you can follow the line down to Fomalhaut.
How was CMB radiation discovered?
Discovered accidentally by microwave receivers by Penzias and Wilson.
How does the CMB support the Big Bang Theory?
Predictions suggested Big Bang was extremely hot, but has now cooled to about 3K.
The CMB corresponds to 3K.
Name a satellite that investigated the CMB and what it discovered.
WMAP mapped the entire CMB.
In which region of the EM spectrum were Quasars first discovered?
Radio
Give two examples, apart from Quasars, of galaxies containing AGNs
Seyfert Galaxies
Radio galaxies
Blazars
N galaxies
How do astronomers believe AGNs are powered?
Mater falling in to their SMBH
