Chapter 9 Space Weather Flashcards
What is the sun consist of?
Hydrogen and Helium
What are the 3 inner layers of the Sun?
Convection zone
Radiation Zone
Core
What are the 3 outer layers of the sun
Photosphere
Chromosphere
Corona
Examples of phenomena that occur on the surface of the Sun
Granules
Solar Cycles
Sunspots
Prominences
Solar Wind
Solar Flare
Coronal Mass Ejections
What makes up the photosphere of the Sun?
Granules
What is a granule? How hot can they get?
Granules are the upper part of the convection zone of the plasma which is extremely hot with a temperature as high as 5700 Celsius
What is the average diameter of a granule?
1000 km
What are sunspots?
Sunspots are dark regions seen on the surface of the sun
Why do sunspots appear dark?
Because their temperatures are lower compared to their surroundings
Characteristics of sunspots?
The location of every large eruption in the photosphere
May last for more than a week
Exists in pairs or groups
What is the solar cycle?
It is the activity of the reappearance and disappearance of sunspots that lasts for 11 years
What is a prominence?
A huge loop of arched column of glowing gases over the sunspot
Characteristics of prominences
Can reach heights of hundreds or thousands of kilometres
Last for several days or months
Can throw out matter from the sun into the space at speeds ranging from 600 to more than 1000 km s{-1}
What is a solar flare
A column of large amounts of charged gases erupting for the Sun and often occurs near sunspots
What are the characteristics of Solar flares?
Attain their maximum brightness level in a few seconds or minutes and become dim after a few minutes or hours
Spout charged gas particles at high speeds into outer space
How long does it take for light and charged gas particles to reach earth respectively?
Light takes 8 minutes to reach earth while charged gas particles take tens of minutes
How are auroras formed?
When charged gas particles or magnetic gas particles collide with atoms and molecules in earth’s atmosphere to produce a stunning light display
What phenomena’s cause auroras to formed?
Solar flares and coronal mass ejections
What are coronal mass ejections?
An ejection of magnetic gas particles
Characteristics of coronal mass ejections
Spout magnetic gas particles at high speeds into outer space
Appears like an expanding cloud
Take 3 days to reach earth
What is solar wind?
When particles in plasma such as electrons, protons and alpha particles that erupt from the sun travel together at high speeds
Characteristics of solar wind
Carries the interplanetary magnetic field along with it
Supersonic Speeds from 250 - 750 km s-1
However speed, temperature and density of solar wind changes along the course of its movement
What is earth’s magnetosphere?
The region in outer space surrounding Earth where the magnetic field in Earth’s magnetosphere is a combination of Earth’s magnetic field and the magnetic field in the region in outer space
How is a magnetosphere formed?
Formed by the interaction between the magnetic field brought by the solar wind and earth’s magnetic field
Compare the change of the shape of the magnetosphere with the number and energy of particles brought by the change of solar wind
As the number and energy or particles brought by the solar wind change, the shape of the magnetosphere also changes
What is the importance of earth’s magnetosphere?
Protect earth from the adverse effects cause by the dangerous particles from the sun or other bodies in the Universe
Examples of the importance of Earth’s magnetosphere
Functions as a biological shield to protect life on earth from the adverse effects of solar wind
Blocks charged particles from reaching earth
Reduces pressure exerted by the solar wind
Describe what would happen if charged particles from solar wind reach earth
Disrupt telecommunication, navigation system and electric power lines
What is space weather defined as
Phenomena that occur on the surface of the sun and in space
What is the date on space weather used for??
Forecast when coronal mass ejections occur and determine the reasons for the occurence of solar flares and coronal mass ejections on the surface of the sun
