astronomy test 2 Flashcards
If you are given a short wavelength, what will the frequency and energy related to a photon look like?
When given a short wavelength, the frequency and energy will be higher. This is opposite for a longer wavelength
What is the order of electromagnetic radiation from lowest to highest energy?
From low to high it is
Radio, microwaves, infrared, visible light (roygbv), ultraviolet, x rays, gamma rays
Between infrared and gamma rays, which will travel faster?
Trick question! All light will travel
at the same speed (speed of light)
What can a star’s spectrum tell us about it?
The peak of the star’s thermal emission tells its temperature
Looking at its spectral lines can show what chemical elements are present
The doppler shift of the spectral lines will help us know the speed it is moving away from us
What is happening when we are looking at a physical object? Ie why can we see it?
We are able to see things because of the visible light that will reflect back into our eyes
What is an absorption line spectrum?
The absorption line spectrum is when white light passes through a cool cloud of gas. Some of the light is absorbed and some is transmitted through the gas
When a star’s spectrum is blue shifted what does its wavelength look like?
When a star’s spectrum is blue shifted its wavelength will appear shorter than normal. The opposite happens for red shift. Its wavelength will appear longer
When a star has a smaller redshift is moving away from us slower or faster than one with a larger redshift?
A star with a smaller red shift is moving away from us slower than one with a larger red shift
Between a red star and a blue star (no doppler shift involved) which one has more thermal radiation?
The blue star will have more thermal radiation because it has a hotter surface temperature than the red star
What is the atomic number?
The atomic is the number of protons in an atom
What is a photon?
A photon is what is emitted when an electron gains or gives off energy jumping from different orbitals
What does it mean when the an atom has the same number of protons, but a different number of neutrons?
When an atom has the same number of protons, but a different number of neutrons it is an isotope
What does it mean when two atoms differ in the number of protons?
When two atoms differ in protons it means they are two different elements
What do we call an atom in its lowest energy level?
An atom in its lowest energy level is called the ground state
What is an atom mostly made of?
An atom contains protons, neutrons, and electrons, but is mostly made of empty space
What is happening when spectral lines appear wider?
When a stars spectral lines appear wider it is rotating
How old is our universe?
Our universe is 4.6 BILLION years old
What is gravitational equilibrium?
Gravitational equilibrium is when thermal gas pressure is pushing out and gravitational force is pushing in
What is the sun made of?
The sun is made of 70% hydrogen, 28% percent helium, and 2% other elements
From the outward in to the core what are the layers of the sun?
Moving in to the core the layers of the sun are
Corona, Chromosphere, photosphere, convection zone, radiation zone, core
What is special about each layer of the sun?
We are able to see the corona during a solar eclipse. It is the source of X-rays
The chromosphere is a source of ultraviolet light
The photosphere is the layer of the sun we can see
The convection zone is where convection is happening (hot plasma rises and falls as cooler plasma)
The radiation zone is the transition zone between the convection zone and the core
Why do sunspots look dark?
Trick question! Sunspots are actually bright, but appear dark against the brighter surface of the
What is the difference between nuclear fusion and fission?
Nuclear fusion: lighter elements fuse into heavier elements (this is what are sun is going through)
Nuclear fission: Heavier elements turn into lighter elements
