SpaceX plans to deploy over 12,000 internet-beaming Starlink satellites within the next seven years to provide reliable high-speed internet globally. The Starlink broadband network will primarily benefit users living in remote and rural regions. Long-term, Starlink customers will be supporting SpaceX’s ultimate goal to enable humans to become a multiplanetary species.

As of today, SpaceX operates approximately 1,740 satellites in low Earth orbit. The company has faced some opposition from competitors and some astronomer critics claiming that SpaceX’s satellite constellation could pose a threat to space environment if the satellites collide with each other, spacecraft, satellites, or space junk in orbit. Some claim it could cause ‘uncontrollable collisions’, known as the Kessler syndrome. However, SpaceX’s Starlink satellites are equipped with an autonomous maneuvering capability to avoid collisions with space debris and other spacecraft by utilizing inputs from the Department of Defense’s debris tracking system. Each satellite can use their on-board krypton-powered ion thrusters to move. This propulsion system can also be used to deorbit a satellite if it stops working. To avoid contributing to space junk the satellites are designed to easily burn up in Earth’s atmosphere. The company also strategically opted to operate the satellites at low altitudes below ~600-kilometers because it enables dead satellites to deorbit in less than five years due to strong atmospheric drag (see graph below for more details). Satellites operating at higher altitudes can take decades to decay.

SpaceX had a conference call with Federal Communications Commission (FCC) representatives to discuss its Starlink Orbital Space Safety plan earlier this month. A presentation PDF document of their discussion was uploaded to the FCC website on August 10. In the document SpaceX representatives outlined what they talked about with FCC staff. SpaceX discussed collision avoidance between Starlink satellites vs. other Starlink satellites, referred to it as ‘Starlink-on-Starlink.’ The company said the satellites are programmed to follow specific instructions in orbit. “Starlink constellation orbits are ‘passively’ deconflicted. Each satellite gets assigned a station-keeping slot,” SpaceX wrote to the FCC, “Every slot is passively deconflicted (via orbit design) against all other slots in the constellation. While satellites remain in their station-keeping slots (via station-keeping burns) they are guaranteed to avoid conflicts with other Starlinks that are also in their slots.” The company said that the “’Active’ collision avoidance system is the second line of defense” and that “the vast majority of Starlink collision avoidance maneuvers are against orbital debris, or 3rd party satellites; not other Starlinks.”

SpaceX also reviewed the Starlink collision mitigation plan to avoid space junk, ‘Starlink-on-Debris.’ “Space is populated with existing debris, tracked by the [United States Military] 18th Space Control Squadron. Starlink utilizes an automated collision avoidance system, ingesting data from the 18th,” the company told the Commission. “Satellites can autonomously evaluate risk and plan avoidance maneuvers, without human input. Humans are still present in an oversight role, as an added measure of safety,” SpaceX wrote in a graphic that details the interaction, pictured below.

SpaceX also discussed about collision avoidance of ‘Starlink-on-Other-Operator’. “Starlink is committed to being a responsible member of the space community. Though Starlink collision avoidance is automated, there are always humans on-call to coordinate and promptly respond to any external operator inquiries,” the company said, “When a maneuverable Starlink satellite sees a conjunction with another satellite: Without intervention, Starlink satellites will assume maneuver responsibility. If another operator prefers to maneuver instead, Starlink satellites can be commanded to remain ballistic for the span of the conjunction event.” The company noted that “due to the lack of industry-standard automated maneuver-responsibility arbitrage methods, Starlink satellites currently default to taking maneuver responsibility for conjunction events with other operators.” The images shown below feature an outline of what SpaceX discussed with FCC representatives, including SpaceX’s collision avoidance for ‘Starlink-on-Human Spaceflight’ and the Starlink satellites ‘End-of-Life Decommissioning' plans.  Author's Note: Thanks for supporting Tesmanian.com. Find me on Twitter: Evelyn J. Arevalo @JaneidyEve.

All Images Source: SpaceX PDF Document To FCC

SpaceX Discusses Starlink Orbital Space Safety Plan With The Federal Communications Commission

by @JaneidyEve via @Tesmanian_comhttps://t.co/p6XCOt3cTO

— Evelyn Janeidy Arevalo  (@JaneidyEve) August 22, 2021