- Muchas notas - Fran Acién

20210906 - 6 Sept - Satellite Geodesey

Vine - La chavala que me saludó en la Biblio Mikkel

For elliptical orbits:

Parameter Abbr. Unit Determines… GPS example
Semi-major axis a meters Size of the eliptical orbit 26,559.8Km
Eccentricity e NaN Shape of the eliptical orbit 0
Mean anomaly M Radians Satellite position

Convert to CIS:

Parameter Abbr. Unit Determines… GPS example
Inclination i Deg Inclination of the orbit relative to equator plane 55º
Argument of perigee \(\omega\) Deg Orientation of the perigee relative to ascending node
Right ascension of the ascending node \(\Omega\) Deg Orientation of the orbit

Kepler Laws

  1. Area velocity is contant in satellites

Mini assignment 1

¿a of GPS satellite?

$$ T = \frac{2 \pi}{\sqrt{GM}} \cdot a^{3/2} \\ a = \big ( \frac{T \cdot \sqrt{GM}}{2 \pi} \big )^{2/3} \\

\text{Result} = 26,5 \cdot 10^6 $$

Mini assignment 2

  • The distance from the Earth to Apoapsis: \(r_a\)
  • The distance from the Earth to Periapsis: \(r_p\)
  • Semi-major axis: a

Eccentricity is given by:

$$ e = \frac{r_a - r_p}{r_a + r_p} $$

¿Show that the distance from center of orbit to focal point is?

$$ \lvert \lvert c - F \lvert \lvert = ae $$

Solution:

$$ e = \frac{r_a - r_p}{r_a + r_p} \\ a + ae = r_a \\ a - ae = r_p \\ \Rightarrow e = \frac{ae}{a} \Rightarrow ae = ae \\ \text{Proffessor answer} \\ a = \frac{r_a + r_p}{2} \Rightarrow ae = \lvert c - F \lvert = \frac{r_a -r_p}{2} $$