15 Our Place In The Galaxy Flashcards
What is our Galaxy called?
Milky Way
What is Milky Way in Latin?
Via Lactea
How far is the Sun from the centre of our Galaxy?
~10 kpc
What is the radius of our Galaxy?
~15 kpc
What type of galaxy is the Milky Way?
Barred Spiral Galaxy
Where are open clusters of young stars found?
In the Spiral Arms
Why can’t we see the centre of the Galaxy using visible light?
The Centre of the Galaxy is blocked by dust and dense gas
What is the Doppler Principle?
The Doppler Principle is that relative motion changes the frequency or wavelength of observed waves. We notice this change mainly with sound waves
What does it mean if the observed wavelength is longer than it should be?
The object is moving away from us
What does it mean if the observed wavelength is shorter than it should be?
The source is moving towards us
What can the Doppler Shifts tell us about the Milky Way?
The received wavelengths are supposed to be 21 cm, but they aren’t exactly. This will tell us the relative velocities of the different parts of the Milky Way and how it’s rotating
What is redshift?
Redshift is receding sources of waves
What is blueshift?
Blueshift refers to sources that are approaching us
What is the used system for the classification of Galaxies?
Hubble Classification System
What is the diagram that classifies galaxies?
Tuning Fork Diagram