Astronautics-principles Of Astrodynamics
@kapilgoela123 (134)
India
November 3, 2006 10:47pm CST
PRINCIPLES OF ASTRODYNAMICSThe few physical principles underlying the study of spacecraft motion are elementary in their basic form. Sir Isaac Newton first formalized the physical laws that determine the motion of a spacecraft: (1) Any body continues in a state of rest, or of constant velocity in a straight line, unless acted upon by external forces. (2) The rate of change of linear momentum of a body is equal to the external force applied. For a body of constant mass, forces are balanced by accelerations. (3) To every action there is an equal and opposite reaction. To these laws Newton added the law of gravitational attraction: any two masses attract each other with a force proportional to the product of the masses and inversely proportional to the square of their separation distance.Johannes Kepler provided the empirical laws that describe planetary motion and allowed a test of Newton's laws. Kepler's laws are the following: (1) The orbit of each planet is an ellipse with the Sun at one focus. (2) The radius vector joining Sun to planet sweeps over equal areas in equal intervals of time. (3) The square of the planetary periods is proportional to the cube of the mean distance to the Sun.
2 responses
@consultrainer (4991)
• India
19 Jul 10
as usual, this is not a final theory. .it was just a postulation and requires a lot of study to be done. .. Ofcourse, none believed them, either COPERNICUS, or CONFUSIOUS, .. when they postulated these sort of theories on heavenly bodies.
same is the case with ISAAC NEWTON.. but, do you know, .. he has some occult studies to his credit.
@consultrainer (4991)
• India
19 Jul 10
there is nothing surprising in the principles proposed by Sir Isaac Newton. Because, it all in the apple that fell on to his head. that sudden fall onto the head, .. called commonly as HEAD-INJURY, might have triggered the hidden emotions about MOTION .. and, he had applied the same to the astro bodies. like the stars and planets.
lols... that is jut to create some fun. It is over 4 years, and you are not online for quite sometime. So, I know this will not be a bother to you anymore.
