Engineers linking Earth and sky Tuesday, 04 June 2019

Space engineers in the US have been busy with the launch of 60 internet satellites as part of an orbiting broadband system that will cross the paths of many of Australia's ground stations 2-3 times a night.

The launch by SpaceX of the satellites from a Falcon-9 rocket from Cape Canaveral is just the beginning of an ambitious plan to launch 12,000 satellites into Earth's skies as part of its Starlink program. Currently there are only about 2000 operational satellites orbiting this planet.

Due to the sheer number planned, there are concerns orbital highways will become congested, resulting in collisions and debris with a follow-on effect. However, SpaceX said its Starlink satellites can track orbital debris and autonomously avoid it and added that 95% of their satellites' construction is made from components designed to rapidly burn up on re-entry.

                      "One of the hardest engineering projects I've ever seen done" – Elon Musk.

Elon Musk, CEO of SpaceX, revealed each Starlink satellite weighs 227kg and is equipped with multiple antennae and a single solar array. On board is an electric propulsion system which expels electrically charged atoms of krypton to provide thrust. This functions to propel each Starlink satellite from its 440km drop-off altitude to the operational height of 550km, and will maintain its correct position and bring it down once its service life is over.

According to Mr Musk, the current Starlink satellite is an iterative design, with later satellites to feature more sophisticated specifications such as inter-satellite links. And while the launch was a success and the roll-out is progressing well, Elon Musk revealed that it was "one of the hardest engineering projects I've ever seen done".

SpaceX has revealed plans for another six launches this year and an acceleration of 720 more satellites to go up in 2020. It is not known when SpaceX's Starlink program will connect to the internet, but on its heels are Amazon, Telesat and OneWeb, all of which are developing their own mega constellations of satellites.

Image: SpaceX's first 60 Starlink satellites, stacked in configuration, in orbit on 23 May 2019.