Notetaker: Space Environment Flashcards
Demarcation, the Sun, Magnetosphere, and Ionosphere
Karman Line
International Standard
100km (62 miles) above Earth’s surface
USSPACECOM domain
U.S. Government Standard
100km (62 miles) above mean sea lvel
Exobase
Scientific Community Standard
500 to 1,000 km (310-620 miles) above Earth’s surface
The sun is composed of what?
- Hydrogen
- Helium
- Misc Gases
The sun is made of 74.9% of what?
Hydrogen
The sun is made of 23.8% of what?
Helium
The sun is made of 1.3% of what?
Misc gases
The sun creates energy through what?
Nuclear Fusion
Core
Rotates like a solid and is where fusion occurs
Radiative Zone
Rotates like a fluid and radiates energy
Tachocline
Generates magnetic field lines and stores magnetic flux
Convective Zone
Rotates like a fluid and transfers heat through convection
Photosphere
Known as the “surface” and is responsible for 99% of solar radiation
Atmosphere
Has 4 sublayers all of which are only visible during an eclipse
What is referred to as “Quiet Sun?”
Solar Minimum
Solar Minimum
- Few to zero sunspots
- Dimmer EUV & x-rays
- Minimum flaring/CME
What is referred to as “Active Sun?”
Solar Maximum
Solar Maximum
- Many sunspots
- Brighter EUV & x-rays
- Frequent flaring/CME
Solar Wind
A stream of charged particles released from the Corona
What solar hazard takes ~3 days to arrive?
Solar Wind
What causes auroras and the plasma trails on comets?
Solar Wind
Solar Flare
A sudden burst of high energy particles and radiation
What solar hazard travels at the speed of light and arrives in ~8 minutes?
Solar Flare
What is responsible for increased atmospheric drag on LEO, the ionosphere becoming more charged, increased GPS errors, and a source of Radio Blackout Storms?
Solar Flare
Solar Energetic Particles
High energy particles emanating from the Sun outside the standard solar wind
What solar hazard arrival varies from 15 minutes to 24 hours?
Solar Energetic Particles
What is responsible for degrading spacecraft components and a source of Radiation Storms?
Solar Energetic Particles
Coronal Mass Ejection
A massive cloud of energetic, magnetized solar plasma launched into space
What solar hazard typically arrives in 3 to 4 days?
Coronal Mass Ejection
What can severely disrupt anything that uses electricity (e.g. power grids, satellites, communication networks) and is a main source of Geomagnetic Storms?
Coronal Mass Ejection
Earth’s Magnetic Field is also known as what?
Geomagnetic Field / Magnetosphere
Where the earth interacts with the solar wind and other solar hazards
Magnetosphere
What is created by the earth’s liquid metal outer core constantly moving?
Magnetosphere
What deflects most solar wind?
Magnetosphere
Define:
Van Allen Belts
Trapped charged particles from the sun
What is populated by trapped solar wind electrons?
The Outer Belt
What is populated by protons from geomagnetic storms on the earth’s night-side?
The Inner Belt
What belt is not very stable due to the unpredictability of solar cycle and solar winds?
The Outer Belt
What belt is more stable and 10 times more energetic?
The Inner Belt
The Ionosphere consists of what?
Plasma (positive ions & free electrons)
The Ionosphere is responsible for what?
Scintillation
Variations in amplitude, phase, and polarization of signals transmitted through a medium
Scintillation
How often does scintillation happen?
Daily
Also is very localized
Scintillation causes what on satellite communications and GPS positioning?
- Signal fading
- Data dropouts
The strength of a storm determine what two characteristics of an aurora?
- Intensity
- Location
The Ionosphere is responsible for northern lights and southern lights, known as what?
- Aurora Borealis (northern)
- Aurora Australis (southern)
Think of Australia in the south.
