Space Flashcards
How do we use line spectra
To identify elements present in the stars
How can we view light
Through a diffraction grating as a continuous spectrum where wavelength and frequency gradually change
What does a diffraction grating do
It’s an optical tool which separates polychromatic light into its constituent wavelengths
What kind of light do hot gasses emit
Only specific frequencies/wavelengths
How does our knowledge of what different gases emit help us
It shows us the composition of a star just by viewing it
What can emission spectra be described as
Chemical fingerprints
What happens to emission spectra in cool gases
These gases absorb the same spectra that they would emit when hot
What happens when we pass the whole continuous spectrum of light through a cool gas
Absorbed frequencies appear as dark lines as they’ve been taken in
Who invented the spectroscope (idk if we need this but it’s in the notes sooo)
Joseph von Fraunhofer
What happens if a sound source is moving relative to the person listening
The wavelength of the pitch is compressed or extended depending on if it’s moving towards or away from the listener
What happens if a sound source is moving towards the listener
The waves are squashed together and wavelength is reduced, so the pitch is higher
What does the concept of moving waves apply to
All types of wave including light
What is the elongation of waves with movement called
The doppler shift
What is the order of the planets
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune
What kind or orbit do the planets have and what do we call this
An elliptical orbit - basically a stretched circle
What produces the tales of comets
Melting ice created as the comet approaches the sun
Where are most asteroids found
Between Mars and Jupiter, because of Jupiter’s gravitational pull
Where are most asteroids found
Between Mars and Jupiter, because of Jupiter’s gravitational pull
Where are most asteroids found
Between Mars and Jupiter, because of Jupiter’s gravitational pull
What other than rocks is in the asteroid belt
A dwarf planet - Ceres
How does a solar system form
- A cloud of ash and dust contracts under gravity.
- Once the gas gets compressed, the temperature starts to rise and the cloud spins.
- This creates a protostar.
What happens in a proton star
Nuclear fusion starts, which is when the star is technically born - the planets form from the swirling dust around the star, but because of the gravity created by the star, most of the matter is pulled in there.
Why are the rocky planets close to the sun
Because the material they’re made out of is heavier, so is more affected by the sun’s gravity
How do we measure distances on planets
Using metres and kilometres
How do we measure distances between planets and the sun
In AU (astronomical unit), which is based on the average distance between the earth and the sun (1.5x10(11)m)
Idk if you need to know this but how many metres is a light year
9,460,730,472,580,800
what is the speed of light
300 million m/s
What happens to some of the matter thrown out from dying stars
It is recycled
How do stars begin life (single word answer)
Protostars
What happens after the protostar phase to stars
Stars enter the main sequence
What happens during the main sequence
When stars are in their main sequence the forces on them balance. Outward radiation and gas pressure forces are balanced by gravity forces.
How does the main sequence end
When the force from gas radiation becomes greater than gravity
What do high and low mass stars become after the main sequence
Red supergiants and red giants
At what point do the forces become unbalanced within stars
When the hydrogen runs out, and it resorts to helium, then gradually heavier elements until iron, when nuclear fusion stops
What happens after nuclear fusion stops because stars have reached iron
The star collapses under its own gravity
What happens to red giant stars after the end of nuclear fusion
They form a white dwarf that gradually cools over time
What happens to red supergiants at the end of nuclear fusion
They quickly collapse and form a supernova (a massive explosion), and then form neutron stars, where the core (originally 1.5 times the mass of the sun) collapses into a space with 12km radius
What happens to very high mass supergiants after supernovas
They collapse with such force that they form black holes
Where are elements heavier than iron formed and ejected into the universe
Supernovas - this is eventually swept up with other gas and dust to form new stars
What is proof that we are a result of an earlier supernova
The existence of uranium on earth
What spectrum shows the temperature and brightness of stars
The Hertzsprung-Russell (H-R) diagram
