northern lights (aurora borealis) katie, rosie, matt
TRANSCRIPT
Northern LightsNorthern Lights(Aurora Borealis)(Aurora Borealis)
Katie, Rosie, MattKatie, Rosie, Matt
RadiationRadiation
Forms of radiation that are Forms of radiation that are reduced by the atmosphere:reduced by the atmosphere:
• UltravioletUltraviolet
• Cosmic RaysCosmic Rays
Cosmic RaysCosmic RaysCosmic Rays are a form of radiation and come Cosmic Rays are a form of radiation and come
from some of the most violent objects in the from some of the most violent objects in the universe:universe:
• SupernovaSupernova• NeutronNeutron• StarStar• Black holeBlack hole
These rays were first discovered by Victor These rays were first discovered by Victor Hess in 1912 by flying hot air balloons to Hess in 1912 by flying hot air balloons to altitudes of 5km he found the air was much altitudes of 5km he found the air was much more ionised higher in the atmosphere.more ionised higher in the atmosphere.
Solar WindSolar Wind
The Earth’s magnetic field can The Earth’s magnetic field can also protect us from radiation also protect us from radiation
from space. Streams of from space. Streams of charged particles evaporate charged particles evaporate
from the surface of the sun in from the surface of the sun in all directions, this is called solar all directions, this is called solar
wind.wind.
Protection from Solar windProtection from Solar wind
The solar winds head towards earth at The solar winds head towards earth at around 400km/second. It would erode around 400km/second. It would erode the atmosphere but the earths the atmosphere but the earths magnetic field deflects most of the magnetic field deflects most of the Solar wind away from the planet. Solar wind away from the planet.
What are the Northern Lights?What are the Northern Lights?
Some solar wind is channelled to Some solar wind is channelled to the north and south poles, where the north and south poles, where they ionise the air and create the they ionise the air and create the
northern and southern lights.northern and southern lights.
Deflecting alpha and beta Deflecting alpha and beta particles.particles.
Beams of alpha and beta particles can be Beams of alpha and beta particles can be deflected because they have opposite deflected because they have opposite
charges, so they deflect in opposite charges, so they deflect in opposite directions. Alpha particles have twice the directions. Alpha particles have twice the
charge of beta particles. charge of beta particles.
Gamma RaysGamma Rays
Gamma rays will not be Gamma rays will not be deflected as they have no deflected as they have no
mass.mass.
MarsMars
Mars has a very thin Mars has a very thin magnetic field, making it magnetic field, making it
very hard to live on.very hard to live on.