Satellites

Piracy is as old as trade itself. When Spain and Portugal began sending treasure fleets carrying gold, silver, and goods across the Atlantic in the 16th century, it didn’t take long for pirates to appear. You might recognize some of the most famous names: Francis Drake, Henry Morgan, Blackbeard, John Hawkins, and others. Some pirates resembled more like companies than the anarchic individuals you might imagine. English piracy often took a special form: privateering, where privately owned ships were authorized by the Crown (via letters of marque) to raid enemy shipping during wartime. ...

Last week I came across this very high-quality image, at first I thought that it must be one of those expensive satellites that cost millions of dollars. Then I started digging and found out how ignorant i am about the recent advances in satellites. Apparently, there are three main orbits used by current satellites [1]: LEO (Low Earth Orbit): ~160–2,000 km; short orbital period (90–120 min); low latency; used for Earth observation, Starlink, ISS. MEO (Medium Earth Orbit) ~2,000–35,786 km; orbital period ~2–12 hrs; GPS/GNSS satellites. GEO (Geostationary Earth Orbit): exactly 35,786 km, equatorial; 24-hr period, appears fixed above Earth; ideal for telecom, TV, weather satellites. Before talking about the satellites, we need to understand the main driver of these advancements. There’s been a huge decrease on rocket failure rates and reduction in the costs of putting them into orbit. To put things in perspective, between 1970s and the 2000s the average launch was about 18.5k USD/kg, while recently the Falcon Heavy only costs around 1.4k USD/kg (more than 10x reduction!!!) [2]. Also, success rate over 99.46% [5]. ...