Download Atmosphere

The Earth’s
Atmosphere
Aerospace
Describing the Atmosphere
• Atmosphere vs. Space
– Humans can live within the atmosphere
– Upper atmosphere no definitive
boundary between one to the other
• Complex mixture of molecules and atoms
• Atmosphere Composition
– 78% nitrogen, 21% oxygen 1% other
gasses
• argon, neon, helium, methane,
hydrogen
Atmospheric Layers
• Troposphere
– The lowest region of the atmosphere. (where we live)
– Altitude ranges from 5-10 miles above sea level
– All clouds & weather conditions occur in this area.
– Temperature will go down with the increase in altitude
– 3.5 degrees (F) for every 1,000 feet gained in altitude
• Known as the standard lapse rate
• Tropopause
– Layer above the troposphere
– Serves as a boundary layer from the stratosphere
– Jet streams occur in this layer
Atmospheric Layers
•
Stratosphere
– Altitude ranges from 19-22 miles above
sea level
– Ozone layer is located in the middle of
the stratosphere
– No atmospheric pressure at this level so
pressurized cabins are needed
– Temperature increases slightly
compared to the previous layers
•
Mesosphere
– Altitude ranges from 22-50 miles above
sea level
– Warmer temps at lower regions from
UV protection
– Lower temps at higher regions
Atmospheric Layers
•
Thermosphere
– Known as the ionosphere
– Altitude ranges from 50-500
miles above sea level
– Has intense electrical activity
– Very high temps in this region
2000F+
– Allows for radio transmission
(reflects radio waves)
•
Exosphere
– Altitude ranges from 500-1000
miles above sea level
– Start blending into space
Atmospheric Pressure
•
Earths gravitational influence is greatest at its core
– Sea level pressure is 14.7 lbs/sq.”
•
Air Pressure decreases the further from the core you go
•
Ex. 35,000 ft. = ¼ the pressure at sea level
•
Are commercial airline cabins pressurized? Why?
•
At very high altitudes pilots need to wear pressurized suits or cells could rupture
Beyond the Atmosphere
•
Near Space
– Area from atmosphere to 10,000 miles
– Area where satellites and the ISS orbits
•
Cislunar Space
– Area from Earth to moon
• 239,000 miles
•
Translunar
– Area from moon to 1,000,000 miles from Earth
– Only probes have discovered this area
•
Interstellar Space
– Distance from star to star in the same galaxy
•
Intergalactic Space
–
Distance from one galaxy to another
Review
1. The Earths atmosphere is comprised mainly of what gas?
78% Nitrogen
2. What is the standard lapse rate?
3.5 degrees (F) for every 1,000 feet
3. What layer has intense electrical activity and the
temperate increases drastically?
Thermosphere
4. Why is it important to wear a pressurized suit at high
altitudes?
Cells in the human body could rupture
Assignment
•Ch.11
•Section A # 1-12