This weekend some believed that Potchefstroom is being invaded by aliens and UFO's, this as a result of a bright dotted line appearing in the night sky, looking like a little train of light moving at high speed, but don't worry we are still safe from alien invasion, these are in fact Starlink Satellites by Elon Musk's company named SpaceX
Who is SpaceX
SpaceX (Space Exploration Technologies Corp) is an American aerospace manufacturer and space transportation services company founded in 2002 by entrepreneur Elon Musk with the goal of reducing space transportation costs and enabling the coloniSation of Mars. It designs, manufactures, and launches advanced rockets and spacecraft.
SpaceX is best known for its reusable Falcon 1, Falcon 9 and Falcon Heavy rockets, and the Dragon spacecraft, which it developed to transport cargo and astronauts to and from the International Space Station (ISS). The company has made history with several key achievements, including the first privately-funded spacecraft to reach orbit, the first privately-funded spacecraft to dock with the ISS, and the first reusable spacecraft to return from low Earth orbit.
In addition to its commercial launches, SpaceX has been contracted by NASA to provide crew and cargo transport services to the ISS, and is also working on developing its Starlink satellite internet constellation and Starship spacecraft for interplanetary travel.
It is the Starlink satellites that you saw in the sky on Friday
What is Starlink?
Starlink is a satellite internet system operated by SpaceX, with its history dating back to the mid-1980s with the concept of low Earth orbit satellite constellations for internet and communication purposes. The project was publicly announced in 2015 and the satellite development facility was opened in Redmond, Washington.
SpaceX began launching Starlink satellites in 2019 and as of December 2022, there are over 3,300 satellites in low Earth orbit. The company plans to deploy a total of 12,000 satellites, with the potential to expand to 42,000 In December 2022, SpaceX announced that it has over one million subscribers.
The cost per unit of capability for the satellites will be much lower than existing satellites, with Elon Musk aiming to "revolutionize space" by mass-producing the satellites, as he did with rockets. The lower cost of smaller satellites is considered crucial for reducing the cost of space-based Internet and communication.
Short history of Starlink
1990s: commercial mega-constellations using around 100 satellites, such as Celestron, Teledesic, Iridium, and Globalstar, were created but all went bankrupt partly due to high launch costs
2004: Larry Williams, former VP of Teledesic and SpaceX VP of strategic relations, established the SpaceX Washington DC office and SpaceX acquired a stake in Surrey Satellite Technology to extend the Internet into space
2014: Elon Musk and Greg Wyler reportedly planned a constellation of around 700 satellites called WorldVu, but plans fell through, and the constellation was later named Starlink and trademarked by SpaceX
2015: Starlink was introduced to the public, with the goal of providing up to 50% of all backhaul communication traffic and 10% of local Internet traffic in highly populated cities and generating revenue to fund SpaceX's Mars endeavors
2016-2017: SpaceX acquired facilities in Irvine, California and consolidated operations in Redmond Ridge Corporate Center for satellite manufacturing and R&D
2017: SpaceX submitted application to the FCC for a non-geostationary orbit satellite system and space debris mitigation plan and submitted plans for a Very-Low Earth Orbit constellation
2021: pre-orders for the public started and $3.5 billion was raised in equity financing to support the operational phase of Starlink
2022: regulatory approval was given in Canada, licenses for services for boats, aircraft, and moving vehicles approved, agreements were announced with Google Cloud Platform and Microsoft Azure
2022: Starlink Business service tier, Starlink For RVs, Starlink Maritime launched, but worldwide speeds decreased due to high demand, concerns raised over potential threat to national security
Why can I see them so clearly?
The satellites orbit low to the Earth, making them appear much brighter than any star and visible to the naked eye, even during twilight hours and in light-polluted urban areas. They are called "megaconstellations" for the way they form constellations, and they are visible because they reflect sunlight, not because they emit light themselves.
Where are these Starlink satellites in space?
Starlink satellites orbit at an altitude of 550 km. At that height, they’re low enough to get pulled down to Earth by atmospheric drag and burn up in a few years, so that they don’t become space junk once they die (a problem SpaceX may hope to tackle using Starship). Each one weighs 500 pounds (227 kg) and measures about the size of a typical coffee table,
To spot the Starlink satellites in the sky, you can use astronomical applications such as Star Walk 2 and Findstarlink. These applications provide up-to-date and accurate information on the position and trajectory of the satellites. In Satellite Tracker by Star Walk, the satellites will appear in the list of objects, and in Findstarlink, you can find them by entering where you are. With these apps, you can enjoy the spectacular view of the Starlink satellites in the night sky and find them easily from your location.
Starlink Controversy among Astronomers
This brightness is great for us to see on the ground, yet the Astronomical SocietIes are not so happy as these bright reflections have the potential to disrupt observations of the night sky. The National Science Foundation and the American Astronomical Society released a report on the situation in August 2020. Discussions among more than 250 experts at the virtual Satellite Constellations 1 (SATCON1) workshop expressed concern that the bright train of satellites marching across the sky will hinder their observations.
In response, SpaceX has begun outfitting their satellites with a blackened sunshade – called VisorSat – that the company hopes will reduce the satellite’s apparent brightness by reducing the amount of sunlight that’s reflected. Initial efforts at mitigating the spacecraft’s impact involved launching a prototype Starlink satellite later dubbed DarkSat in 2021, which featured a black antireflective coating. Ground-based observations of DarkSat in orbit found it half as bright as a standard Starlink satellite, which is a good improvement, according to experts, but still far from what astronomers say is needed.
DarkSat was with a typical Starlink sibling using a two-foot (0.6-m) telescope at the Ckoirama Observatory in Chile and found that although DarkSat’s antireflective coating rendered it invisible to the unaided eye, it remained far too bright to avoid interfering with the Vera C. Rubin Observatory in Chile – and other major telescopes. Additionally, DarkSat’s darker colour retains too much heat, so the company is sticking with the visor alternative for now instead.
Conclusion
The Starlink satellites are a promising solution for bringing high-speed and low-latency internet services to remote and rural areas. However, the astronomical community has expressed concern over the satellites' brightness and potential to disrupt astronomical observations. SpaceX has taken steps to mitigate these concerns by outfitting its satellites with
In the interim we will see more of these UFO's crossing our sky and stare in amazement knowing that there is a South African behind not just Starlink, but also the plan to go to Mars