1 Intro to Orbital Mechanics

Question 1

What is Kepler’s 1st Law?

Answer 1

Law of Ellipses

Question 2

What is Kepler’s 2nd Law?

Answer 2

Law of Equal Areas

Question 3

What is Kepler’s 3rd Law?

Answer 3

Law of Harmonics

Question 4

What is Newton’s 1st law?

Answer 4

Law of Inertia

Question 5

What is Newton’s 2nd law?

Answer 5

Law of Changing Momentum

Question 6

What is Newton’s 3rd law?

Answer 6

Reaction

Question 7

Force of Attraction is directly proportional to…

Answer 7

…the product of their masses.

Question 8

Force of Attraction is inversely proportional to…

Answer 8

…the square of the distance between them.

Question 9

The point at which an Earth orbiting object is CLOSEST to the Earth is known as…

Answer 9

…Perigee.

Question 10

The point at which an Earth orbiting object is FURTHEST AWAY to the Earth is known as…

Answer 10

…Apogee.

Question 11

How many Keplerian Classical Orbit Elements are there to understand an determine a satellite’s orbit?

Answer 11

6

Question 12

In KCOEs. The size of the orbit is given by…

Answer 12

Semi Major Axis

Question 13

In KCOEs. The shape is given by…

Answer 13

…Eccentricity

Question 14

In KCOEs. The tilt of an orbit is given by…

Answer 14

…Inclination

Question 15

In KCOEs. The twist of an orbit is given by…

Answer 15

…right ascension of the ascending node

Question 16

In KCOEs. The rotation of the orbit is given by…

Answer 16

…the Argument of Perigee.

Question 17

In KCOEs. The satellite’s position on orbit is given by…

Answer 17

…True Anomaly

Question 18

Describe a LEO orbit (altitude and period)

Answer 18

~150 km to 2000 km

~90 mins

Question 19

Describe a Polar Orbit.

Answer 19

A polar orbit is one which passes over the North and South Poles on each revolution

Question 20

What is an advantage of a Polar Orbit?

Answer 20

Over a period of time, the satellite can observe the entire planet

Question 21

Describe a Sun-Synchronous Orbit

Answer 21

Enables a satellite to pass over a given point on the Earths surface at the same local mean solar time.

Question 22

Describe a MEO orbit (altitude and period)

Answer 22

~2000 km to 35862 km

~11hrs 58 mins

Question 23

Describe a Semi-Synchronous Orbit

Answer 23

SemiSOs have an orbital period equal to half of the average rotational period of the body being orbited.

And orbit in the same direction as the rotational body it is orbiting.

Question 24

What are the two kinds of HEOs?

Answer 24

Molniya

Tundra

Question 25

Describe a Molniya HEO (altitude, period and inclination)

Answer 25

~600 km to ~40,000km ~11 hrs 58 mins ~63.4 deg Provides long loiter time over the hemisphere of interest

Question 26

Describe a Tundra HEO (altitude and period)

Answer 26

~25,000 km to ~46,000 km ~23 hrs 56 mins

Question 27

Describe a Geosynchronous Orbit (GEO) (altitude and period)

Answer 27

35,863 km 23 hrs and 56 mins Orbits at the same period as the Earth and appears to ‘hang’ over the same point on the Earths surface

Question 28

Describe a Geostationary Orbit (GSO) (altitude and period)

Answer 28

35,862 km 23 hrs 56 mins Specifically orbits in-line with the Earths equator