This show is dedicated to Procrastination, the avoidance of doing a task which needs to be accomplished.

I've been trying to record this particular show for ages but I can never seem to finish it. I find the topic just too interesting. When I start then I get distracted by some other aspect. Every time I try to record it Murphy gets in the way, with lost recordings and broken cards etc. This is the email that prompted this show.

-------- Forwarded Message --------

Subject: TWAT - Satellite communications

Date: Tue, 13 Dec 2005 12:00:54 +0100

Hi Droops,

I heard your call for content and I'd like to send you some shows. I

don't have a lot of spare time with work and a young family so I can't

do a regular show but I can send you a series on a topic. I was

thinking of doing a series on Satellite Communications.

...

Ken

https://en.wikipedia.org/wiki/Murphy%27s_law

So after eleven years, I set the deadline of episode 2000 to force myself to finish this show.

Let's start.

What are orbits ?

https://en.wikipedia.org/wiki/Orbit

In physics, an orbit is the gravitationally curved path of an object about a point in space, for example the orbit of a planet about a star or a natural satellite around a planet. Orbits of planets are typically elliptical, and the central mass being orbited is at a focal point of the ellipse.

Newton's cannonball was a thought experiment Isaac Newton used to hypothesize that the force of gravity was universal, and it was the key force for planetary motion. It appeared in his book A Treatise of the System of the World.

https://en.wikipedia.org/wiki/Newton%27s_cannonball

https://upload.wikimedia.org/wikipedia/commons/7/73/Newton_Cannon.svg

No orbit

Suborbital trajectories, trajectory intersects the atmosphere so that it does not complete one orbital revolution.

Orbital trajectories (or simply "orbits")

Open (or escape) trajectories

It is worth noting that orbital rockets are launched vertically at first to lift the rocket above the atmosphere (which causes frictional drag), and then slowly pitch over and finish firing the rocket engine parallel to the atmosphere to achieve orbit speed.

Once in orbit, their speed keeps them in orbit above the atmosphere. If e.g., an elliptical orbit dips into dense air, the object will lose speed and re-enter (i.e. fall). Occasionally a space craft will intentionally intercept the atmosphere, in an act commonly referred to as an aerobraking maneuver.

Types of orbits

There are many ways to classify orbits

https://en.wikipedia.org/wiki/List_of_orbits

The choice of which orbit to use is based on the intended purpose of the satellite.

Centric classifications: Based on what they orbit

Altitude classifications: Based on how high they are

Inclination classifications: Based on the angle of rotation with respect to the Equator.

Eccentricity classifications: Based on their path

Synchronicity classifications: Based on how often they rotate

Low Earth orbit (LEO)

0 to 2,000 km (0–1,240 miles).

0 km / mi - Sea Level.

37.6 km / 23.4 mi - Self Propelled Jet Aircraft Flight Ceiling (Record Set in 1977).

215 km / 13