Space: Stormy Weather In LEO

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February 17, 2022: SpaceX recently put 49 of its 227 kg (500 pound) Starlink satellites into orbit and lost 40 of them because of an unexpected geomagnetic storm caused by a burst of energy from the sun. Normally these energy bursts are no problem for satellites, but the smaller Starlink satellites were caught at a vulnerable moment. Starlink satellites are not taken directly to their 540-kilometer high LEO (low earth orbit) by the SpaceX SLV (satellite launch vehicle), but to a lower orbit of about 200 kilometers. This enables the SLV to carry more satellites which reach their ultimate orbital height by using their low power electric thrusters that use small quantities of krypton gas to adjust the orientation of the satellite. If any of the satellites are defective, as if their thrusters don’t work, they will self-destruct by falling into the earth’s atmosphere and burning up. Normally the Starlink thrusters successfully get each satellite to its higher orbit and are later used to aim the satellite towards a lower orbit when that satellite breaks down or is no longer needed. Without the thrusters it would take a dead satellite a lot longer to drift lower and ultimately take the final plunge into the thicker atmosphere where it is vaporized.

Geomagnetic storms are visible on earth because they cause the northern lights. That phenomenon is caused by the geomagnetic storm heating up the atmosphere present in the lower LEO orbital space. That’s what doomed the 40 Starlink satellites, which were just beginning to move into a higher orbit when the thin atmosphere they were in was heated up and became more difficult to move through. The low-energy thrusters could not handle this. Nine of the Starlink birds defied the odds and survived. The design of the Starlink satellites will not be changed because getting hit by an energy burst from the sun at the worst possible moment is a rare event that can be made less likely by taking geomagnetic storm timing into account before allowing the SLV to take off. Weather is already a consideration for this, but only winds or storms closer to earth.

The full Starlink system will consist of over 11,000 small satellites and SpaceX met its goal of having nearly 2,000 satellites in orbit by 2021. Starlink offers high-speed Internet service worldwide and is not concerned with objections by foreign nations. This is especially true when one Chinese backed network, LinkSure, promises to provide “free wi-fi worldwide” and make money with ads and reselling user data. There is a catch, as LinkSure is subject to Chinese censorship, while Starlink is not. This is what concerns nations like China, Russia, North Korea and Iran that all seek to impose tight control over local Internet users.

Starlink was designed for users in remote areas where there was no affordable Internet service. Starlink impressed early users, including those reviewing it for various tech and consumer publications, because it worked. Starlink delivered download speeds of over 50 Mbps and upload speeds of 15 or more Mpbs. Most Internet users worldwide get by with 10/5 Mpbs and high-end users expect what Starlink supplies. Currently Starlink costs $499 for the small dish used to send and receive signals and a “modem” to make the Starlink signal compatible with current computers, plus $99 a month for service. Many Chinese, Russian and Iranian Internet users have the cash and courage to use foreign satellite communications services that are not censored and StarLink is an attractive solution because of its small satellite dish, which is 110mm (four inches) wide and 479mm long, and weighd four kg (8.8 pounds. It has to be mounted outside but can be under a then non-metallic material that will conceal from the thought police.

For China, Starlink is but the latest irritation from SpaceX. China is trying to recreate the reusable boosters that make SpaceX launches so much cheaper without making their launch services even more unreliable than SpaceX. From a military point of view, Starlink is a major problem because China has been creating anti-satellite weapons that could cripple a conventional satellite communications and surveillance system. It would be much more expensive, time-consuming and uncertain to cripple an LEO network that is built around the concept of surviving major damage and continuing to operate. The Chinese solution is to go after SpaceX from many directions using bribes, intimidation, propaganda, litigation and whatnot to take down a major, unexpected, threat.