Space and Orbits Flashcards
What is space?
- low density air molecules, vacum,void,space
- The karman line at 100km altitude is an arbiterary boundary of the atmosphere and space
- The atmosphere extends
for 480 km and
continues to merge with
space as air pressure
approaches a vacuum - There is no distinct
boundary between Earth
and space
Satellites are generally at
least 400-500km altitude
Orbits
-
Orbit:
* curve path around a celestial object -
Path:
* created from gravitational attraction between the two objects
The orbit is the effect of
continuously falling towards
the object..
Orbits
Newton’s cannonball experiment:
Newton deduced:
* significant thrust
* enough altitude (from lift)
* cannonball can maintain:
- circular orbit around Earth
- this is what setelits do
Types of orbits
for midterm do not use google use the class material!
- Low-Earth orbits
- Close Elliptical Orbits
- Far Elliptical Orbits
- Geostationary Orbits
1.Low-Earth orbits
Speed: 26,600km/h(objects in these orbits travel at..)
Altitude:400km
Applications:
* Earth observation
* human space flight
* microgravity experiments
* international space station
Susceptible to:
* atmospheric drag
* orbital decay(oxigen molecules,decaying the object)
Will the ISS(international space station) eventually be forced to Earth?
as its contatly being pulled down to earth by gravity/orbits
no. because although it is being pulled down due to orbit decay once in every now and then there is a boust where ISS is trown back up/to higher latitude
the good thing about the ISSc coming down now and again is that makes putting people in that station becames easier as they dont have to go to such distances to arrive at ISS
2.Close Elliptical
Speed: 27,432 km/h
Altitude: 600-2000 km
Application: statelites in this orbit are used for earth observation
3.Far Elliptical
Speed: 14,000 km/h(slower speed)
Altitude:20,182 k
Applications:Global Navigation Satellite systems (GNSS)
- GPS
- find my phone
4.** Geostationary Orbits**
speed: 10,080 km/h
altitude: 35,786 km
applications: Weather satellites,
-always looking at the exact same portion of the earth.
space junck
things such as satelits that are not used anymore,passed their life time but just stay in orbit
Risk of space Junk
- Difficult to launch new satellites
- They could get hit by old ones and other junk
- More dangerous/difficult for space exploration by people
- Due to higher risk of getting hit by debris
Impacts on Earth Observation
Kessler Effect
Kessler Effect
- Exponential Growth
- the belif as more things are hit when going up more space junk is created which will hit more things that will create more space junk…
- Scientists predict that close encounters between satellites and debris will rise by…
- 50% by 10 years
- 250% by 2059
20,000 object bigger than a softball being tracked
What can we do?
- Debris reduction programs
-Send satellites into space designed to reduce junk - Ex. Harpoon or net capture
- Develop technologies to avoid oncoming space debris
-Ensure newly launched satellites can remove themselves
from space - Implement stronger international agreements
types of technology to clean space junk
slide 25,26,27
solutions that can be done now are 25 and 26
