10-03-2011, 09:32 AM
Presented by:
APRAJITA CHANDEL
DHIRAJ PATHANIA
PRIYANKA CHOUDHARY
NAVNEET THAKUR
NIT HAMIRPUR
ANALYSIS OF THE MOTION OF SATELLITES.pptx (Size: 825.37 KB / Downloads: 59)
ANALYSIS OF THE MOTION OF SATELLITES
INTRODUCTION
• Satellites are of wide importance in our daily life. Today, all advancements are dependent on our surveys and a large no. of surveys are dependent on satellites.
• Motion of satellites in space includes the concept of orbital velocity, types of orbits, escape velocity etc.
WHAT ARE SATELLITES?
Satellite is generally a celestial body which revolve around other such body generally heavier than it.
For instance, Moon revolves around the earth, so it is a satellite of Earth.
TYPES OF SATELLITES
Based on origin, satellites are of two types:
Natural Satellites
Artificial Satellites
Further classification:
Polar satellites/Geostationary satellites
Communication satellites
Spying satellites
SATELLITE ORBIT
An orbit is the path in which satellite moves.
An orbit may be circular, elliptical, parabolic or even hyperbolic.
But mostly circular or elliptical orbit is preffered because in these cases we can make use of natural gravitational force to drive satellite in its orbit.
TYPES OF ORBIT
GEOSYNCHRONOUS ORBIT
POLAR ORBITS
WALKING ORBITS
SUN SYNCHRONOUS ORBITS
MOLNIYA ORBITS
HOHMANN TRANSFER ORBITS
KEPLER’S THREE LAWS
1. THE LAW OF ELLIPSE
2. THE LAW OF EQUAL AREAS
3. THE LAW OF HARMONIES
THE LAW OF ELLIPSE
The paths of the planets about the sun are elliptical in shape, with the centre of sun being located at one focus.
THE LAW OF EQUAL AREAS
An imaginary line drawn from the center of the sun to the sun of the planet will sweep out equal areas in equal intervals of time.
THE LAW OF HARMONIES
The ratio of squares of periods of any two planets is equal to the ratio of the cubes of their average distances from the sun.
LAUNCHING OF A SATELLITE
The launchof a satellite consists of a period of powered flight during which the vehicle is
lifted above the Earth’s atmosphere and
accelerated to orbital velocity by rocket or launch vehicle.
ORBITAL VELOCITY
It is that velocity which makes the satellite to remain in its orbit by utilizing planet’s gravitational pull as centripetal acceleration.
Also,
Hence,
ESCAPE VELOCITY
It is defined as the particular velocity which is able to set a particle free from gravitational field of the planet.
WHY A SATELLITE DOES NOT ESCAPES OUT ITS PATH?
The orbital velocity provided to it less than escape velocity for that planet
The effect of gravitational force of outer celestial bodies is also utilized to counterbalance the effect of gravitational attraction of planet.
SATELLITE FAILURE
Reasons for satellite failure are:
Defects in satellite launching
Hohmann Transfer
Satellite failure in mission orbit