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Unexpected solar weather is accelerating satellites' orbital decay
- jaywalk 4y agoIs the word "plummet" really appropriate here? They're talking about falling at a rate of 0.001mph, which is much faster than expected but hardly a "plummet."
- jcims 4y agoI don’t really pay attention that closely, but space.com is a common theme when i see hacky stories about space/astronomy.
- martinky24 4y agoPop-sci articles... Always disappointing
- dylan604 4y agoJust finished reading the article with the exact same question in mind. Plummet gets the clicks though, so to the website, it is appropriate. It could also be argued it's a sense of perspective. Something that falls at the rate of 2km per year suddenly in a matter of months starts to fall at a rate of 20km per year could seem like plummeting when you're the one tasked with keeping it alive or the person that paid for it to be there for 10 years to see it suddenly shortened to 2 years. It's a stretch, but we all love hyperbole
- uranium 4y agoThis. To space folks, that is plummeting. It's enough of a difference, and a surprise, to have a significant effect on business models.
- Aachen 4y agoIt's a significant difference that has a real impact on the satellites. But we also don't say that airplanes plummet when landing or elevators when going down. To me at least, plummet signals it's a matter of seconds or, perhaps from great altitude, minutes until it hits the bottom. So to me, and that's knowing a thing or two about space, this title is just clickbait and not a good description of the phenomenon observed even for a techy public like HN.
- dylan604 4y agoWe absolutely refer to planes as plummeting, when the situation warrants. This article wasn't written for HN. It was written for the general audience that peruses Space.com. Because someone found it interesting and posted to HN is pretty much the only reason it is on HN. Space.com didn't submit it in hopes of gaining attention by a hypercritical audience. Yes, I agree it is click bait. I'm just playing devil's advocate to some of your weaker arguments.
- thaumasiotes 4y ago> We absolutely refer to planes as plummeting, when the situation warrants. Yes, and landing is not one of those situations. To describe a plane as "plummeting" requires that it crash (or recover and stay airborne) rather than landing. Or in other words, Aachen's claim that "we also don't say that airplanes plummet when landing" was correct in every particular.
- deleted 4y ago[deleted]
- CodeWriter23 4y agoWell at that rate, it will crash into the Earth in…never
- deleted 4y ago[deleted]
- dr_orpheus 4y agoBut it will though. The lowest satellites are at an altitude of 460 km above the Earth. And the decay of the satellite in to the Earth is exponential [0] so the unexpected drop is a significant impact on the lifetime of the spacecraft. You can see from the plot in that Orbital Decay that there is an altitude that it starts dropping very rapidly. So they may have expected it de-orbit in approximately 10 years, but now the de-orbit could be something like 5 years. https://en.wikipedia.org/wiki/Orbital_decay#/media/File:Altitude_of_Tiangong-1.svg https://en.wikipedia.org/wiki/Orbital_decay#/media/File:Alti...
- CodeWriter23 4y agoYou don’t think it will burn to ashes during re-entry?
- Eddy_Viscosity2 4y agoI'm surprised they didn't go all out and call 'solar weather' 'extreme nuclear explosion activity on the sun'. I'm mean, if its for the clicks, why not.
- mc32 4y agoYeah, plummet is like straight down till it hits something. Given it's root is in "plumbum" it's not surprising and yes, this is used incorrectly. Not being prescriptive, but this usage is pretty misleading.
- pempem 4y agoWell now that we've determined that plummet maybe isn't the right word to use, shall we discuss the fact that satellites are unexpectedly falling from the sky in yet another climate change that we had not predicted?
- mc32 4y agoWhile solar phenomena influences climate, this aspect is not human induced. We have put artificial satellites up there, in earth orbit, but they are not causing solar eruptions or solar flares. We don't understand solar "climate" enough to say that it's changing (cycle frequency, amplitude, etc).
- bityard 4y ago> We don't understand solar "climate" enough to say that it's changing (cycle frequency, amplitude, etc). We certainly do know a fair amount about the sun's "climate": https://en.wikipedia.org/wiki/Solar_cycle https://en.wikipedia.org/wiki/Solar_cycle The sun has an 11-year solar cycle where each cycle has a period of low and high sunspot activity and currently we are just starting Cycle 25 with a corresponding uptick of solar flare activity.
- jtbayly 4y agoIf only we hadn't been burning fossil fuels, the sun wouldn't be punishing us like this!
- pempem 4y agoClimate of the sun. ugh. climate of the sun obviously.
- izzydata 4y agoWow, so you are telling me satellites are falling to earth and burning up in the atmosphere? No? Oh.. ok.
- kzrdude 4y agoNo? Yes. They always do this. The only question is how fast. They'll fall and burn eventually.
- perihelions 4y agoThey also say Starlink fully lost 40 satellites to solar weather (were decelerated rapidly enough to burn up in the atmosphere, before their orbits could be rescued). There's a range of outcomes. Thread about that: https://news.ycombinator.com/item?id=30267587 https://news.ycombinator.com/item?id=30267587 (488 comments)
- mirashii 4y agoFor those who don’t click through to the other thread, I’d say that solar weather contributed, but the root cause was more an overzealous safe mode induced by the operations team that didn’t leave time to recover. A better operations plan would’ve shortened the safe mode duration to ensure that they attempted to raise their orbit even if it meant deploying during the solar event. Letting safe mode destroy the satellite to mitigate a probabilistic risk is just bad planning. Take the chance and deploy anyways and hope you get lucky.
- adolph 4y ago> Take the chance and deploy anyways and hope you get lucky. If they got unlucky they might have spiked a space in which another satellite could have orbited (no pun intended).
- mirashii 4y agoThere’s not really a shortage of space, even in LEO. This isn’t a place where Kessler syndrome or orbital slots are really a concern.
- daniel-cussen 4y agoCome on, 40 satellites is not all that much for Spacex.
- mirashii 4y agoEven on the cheap end of estimates at 250k/each, that's still 10 million in hardware alone, not to mention launch costs, opportunity cost of delaying operations, etc. But really, that's neither here nor there, the point of the comment is that a combination of an unexpected solar storm and the operations procedures followed for dealing with them lead to a possibly unnecessary loss of satellites. Just because they have more doesn't mean they're happy about losing out on millions of dollars of hardware.
- colechristensen 4y agoYes, orbit decay having gone up by a factor of ~10 is indeed plummeting. You park things in low earth orbit so that they don't stay up forever and indeed come down in reasonably small human-scale timeframes. Usually on the time scale of decades, sometimes more, sometimes less. If you designed a satellite to stay up for 10 years, it'll suddenly only be able to stay up a year, that's the scale of these things. Again it's an exponential thing, a seemingly small scale change in the slow part makes the fast part come quite a lot sooner.
- GekkePrutser 4y agoBut this space 'weather' won't last forever right? Won't it go back to the old decay rate after this? So if it lasts a week, the lifetime will be reduced by 10 weeks? Still a lot but something you can cope with.
- colechristensen 4y agoThere are events measured in minutes, hours, and years (or decades). We’re ramping up to a maximum which should happen in a few years but activity has been above predictions. We don’t understand the Sun dynamics all that well, but what’s happening now is a little weird beyond expectations and might be something that continues for years.
- BitwiseFool 4y agoI think the primary objection is that to the vast majority of people 'plummet' implies the satellite is suddenly and violently falling from the sky - it's the kind of word people would describe an airplane crash with. However unless the author happens to know a lot about orbital mechanics (or they've played Kerbal Space Program) they probably just picked an expressive word for the sake of a compelling article rather than something that would give a better picture to the layperson.
- colechristensen 4y agoIt's a dumb objection. A mission manager was quoted using the word "diving". It isn't the journalist but the nitpicking commentors who are clueless. The headline accurately enough conveys what is happening and the article articulates it well. Orbital mechanics isn't intuitive enough for there to be perfect fit words given human experience, human timescales, "plummet" is fine.
- dang 4y agoAlright you guys, they are no longer plummeting in the title above. Let's talk about the interesting bits now!
- cperciva 4y agoI would have said "... is accelerating satellites' orbital decay".
- dang 4y agoOk, it's up there now. Thanks!
- B1FF_PSUVM 4y ago"exponentially" (pet peeve, sorry)
- deleted 4y ago[deleted]
- not2b 4y agoToo many HN threads just seem to be people arguing about the appropriateness of the title. The article addresses a significant and interesting issue that's going to have major negative effects on business models, as well as some positive effect on space junk. I think they did a decent job, at least for an article intended for the general public, and I'm glad I read it. And yes, the word "plummet" is an exaggeration. But that isn't a big deal.
- RosanaAnaDana 4y agoHN: come for the pedentry, stay for the pedentry on pedentry.
- jtbayly 4y agoIt's spelled "pedantry." :)
- formerkrogemp 4y agoPedantry for the peasantry. And pleasantly peering for pedantry on HN.
- birdyrooster 4y agoBike shedding at work
- vsllc 4y agoI am thinking about a commercial data product to address the situational awareness need here. It feels daunting though, because customers would be the likes of SpaceX and other intimidating entities. If anyone has thoughts, or is interested, please send me an email. (Contact info in profile!) Thanks.
- visviva 4y agoCommercial SSA is getting to be a busy... space. Have you seen what others are doing in that area? How does your idea differ?
- colechristensen 4y agoWith NASA and related space weather data products and internal tracking of satellites being a core competence of companies like SpaceX, I don't necessarily see where a commercial data product would fit or provide value. Unless you're actually going to launch orbital assets and have some significant scientific work, I'm just not sure. Some competition: http://acswa.us/about/members.html http://acswa.us/about/members.html
- rcardo11 4y agoI'm wondering if this solar cycle can be a reason for the recent wild summer temperatures? Anyone here can confirm?
- readerbaza 4y agohow dare you! it's the evil co2 When the warning signs are ignored because they don't fit the political propaganda, then sure...it's "unexpected"
- daltont 4y agoHyperbolic headlines plus the fact the people tend to not read anything except the headline (a form Lem's law IMO) is part of the disinformation problem.
- zoomablemind 4y agoThere were some space tech startups planning to provide a kind of tug-service to satellites on the low orbit. Not sure if any viability for this is on the near-future horizon. Space tugs as a service: https://spacenews.com/space-tugs-as-a-service-in-orbit-service-providers-are-bracing-for-consolidation/ https://spacenews.com/space-tugs-as-a-service-in-orbit-servi...
- kgc 4y agoI wish we could go back to the days of non-clickbait headlines.
- dragontamer 4y agoWhen exactly did those days exist? * "Destruction of the Warship Maine was the work of an Enemy. $50,000 Reward~" https://sophia.smith.edu/fys169-f19/wp-content/uploads/sites/450/2019/12/Journal98.gif https://sophia.smith.edu/fys169-f19/wp-content/uploads/sites... * There's also the fake propaganda Ben Franklin pushed so that the 1776 revolution would have the moral high ground. (Ben Franklin fabricated the "Scalping" of USA's early citizens to fake a war-crime, to make the British look more monstrous). https://founders.archives.gov/documents/Franklin/01-37-02-0132 https://founders.archives.gov/documents/Franklin/01-37-02-01... I'm not sure if there ever was non-clickbait headlines. In fact, the further back in history you go, the more clickbait, and even fully fake, information seems to exist.
- FunnyBadger 4y agoThis is simply part of the solar cycle. And it's a standard part of satellite planning when it comes to operational quality and reliability to account for solar cycle radiation effects. This is an ignorant fear article and/or an article written by someone who knows NOTHING about space launch and design. (I used to be a military rocket scientist specializing in radiation effects on space electronics many moons ago).
- kmbfjr 4y ago>By coincidence (or beginner's luck), the onset of the new space revolution came during that sleepy solar cycle. Apparently not simply part of the solar cycle when new types of spacecraft (lacking typical propulsion systems) haven’t been in orbit during a high activity solar peak. There are some points that are alarmist. “Plummet” isn’t something that seems to happen.
- walrus01 4y agoI concur with this, and also, one possible solution to this from a technical perspective is to increase the amount of fuel carried for ion/hall effect and similar thrusters (high specific impulse, low thrust) for periodic orbit raising maneuvers to extend lifetime. Theoretically, as $ per kg launch costs come down with things like reusable falcon 9, it makes it much less costly to equip medium sized LEO satellite with more fuel than it might have costed 10 or 15 years ago. Or if you have something that needs to orbit really low and minimize drag/maximize lifespan, you could design it to be particularly aerodynamic and shaped like this: https://en.wikipedia.org/wiki/Gravity_Field_and_Steady-State_Ocean_Circulation_Explorer https://en.wikipedia.org/wiki/Gravity_Field_and_Steady-State...
- KennyBlanken 4y agoThe article at length describes how this solar cycle is different from prior cycles and forecasts. > This drag also helps clean up the near-Earth environment from space junk. Scientists know that the intensity of this drag depends on solar activity — the amount of solar wind spewed by the sun, which varies depending on the 11-year solar cycle. The last cycle, which officially ended in December 2019, was rather sleepy, with a below-average number of monthly sunspots and a prolonged minimum of barely any activity. But since last fall, the star has been waking up, spewing more and more solar wind and generating sunspots, solar flares and coronal mass ejections at a growing rate. And the Earth's upper atmosphere has felt the effects. > In late 2021, operators of the European Space Agency's (ESA) Swarm constellation noticed something worrying: The satellites, which measure the magnetic field around Earth, started sinking toward the atmosphere at an unusually fast rate — up to 10 times faster than before. > By coincidence (or beginner's luck), the onset of the new space revolution came during that sleepy solar cycle. These new operators are now facing their first solar maximum. But not only that. The sun's activity in the past year turned out to be much more intense than solar weather forecasters predicted, with more sunspots, more coronal mass ejections and more solar wind hitting our planet. > "The solar activity is a lot higher than the official forecast suggested," Hugh Lewis, a professor of engineering and physical sciences at the University of Southampton in the U.K. who studies the behavior of satellites in low Earth orbit, told Space.com. "In fact, the current activity is already quite close to the peak level that was forecasted for this solar cycle, and we are still two to three years away from the solar maximum." > Stromme confirmed those observations. "The solar cycle 25 that we are entering now is currently increasing very steeply," she said. "We do not know if this means that it will be a very tough solar cycle. It could slow down, and it could become a very weak solar cycle. But right now, it's increasing fast."
- mturmon 4y agoAs people are pointing out, the rate of orbital decay does matter (even if it's not a "plummet"!) -- because everyone concerned knows that solar activity should be increasing to some extent in 2022 as a new solar cycle takes hold. This plot of sunspot activity, and the (highly correlated) 10.7cm radio flux, indicates that the current cycle (cycle #25) is rising much faster than typical: https://www.swpc.noaa.gov/products/solar-cycle-progression https://www.swpc.noaa.gov/products/solar-cycle-progression As you can see, cycle #24, which ended in 2019, was quieter than expected (annoying to solar physicists who only see a few cycles within their whole career) -- so it's actually very interesting that Cycle #25 is starting out with a bang. NOAA is the main US government agency tasked with monitoring/predicting solar activity for the protection of ground and space systems. The main facility is the Space Weather Prediction Center which is in Boulder, CO -- that's the data source of the above plots. The SWPC centerpiece used to be a control room with a bunch of people looking at computer monitors filled with various real-time and historical time series. We don't know why some cycles are less intense, and the last few cycles have generally been on a downward trend (e.g., https://en.wikipedia.org/wiki/Solar_cycle#Sunspots https://en.wikipedia.org/wiki/Solar_cycle#Sunspots). So again, it is indeed quite interesting to see this high activity - if it holds up.
- zackees 4y agoSo this effect is caused by more solar wind slamming into the atmosphere at 100’s of km/hr and is so powerful that it’s CAUSING THE ATMOSPHERE TO HEAT UP AND EXPAND? Does the global warming models take this into effect? This seems like an unfathomable amount of energy.
- mturmon 4y agoSolar irradiance variations amount to a bit less than 0.1% over the solar cycle. It used to be thought solar-cycle variations (the 11-year period) could be a significant contributor to climate change. This turned out not to be the case...that was pretty much known by the early 2000s. Other irradiance variations, due to orbital variations called Milankovich cycles, happening in the 10,000's of year range, do appear to influence climate. Of course, the extremes we're seeing now are not on the 10,000-year time scale.
- jhgb 4y agoIt's causing the uppermost layers of atmosphere to expand. That's less than an unfathomable amount of energy because the uppermost layers of atmosphere are extremely rarefied, to the extent they don't even behave like gases.
- Treblemaker 4y ago(December 19, 2020) "The consensus view of an international panel of 12 scientists calls for the new cycle, Solar Cycle 25, to be small to average, much like its predecessor, Solar Cycle 24. But a prominent astrophysicist at the National Center for Atmospheric Research, Scott McIntosh, foresees the sun going gangbusters. The cycle is already off to a fast start, coinciding with the recent publication of McIntosh’s paper in Solar Physics. The study, with contributions from several of his colleagues, forecasts the nascent sunspot cycle to become one of the strongest ever recorded." [0] https://www.washingtonpost.com/weather/2020/12/19/solar-cycle-prediction-mcintosh/ https://www.washingtonpost.com/weather/2020/12/19/solar-cycl...
- Treblemaker 4y agoUpdate on the prediction: (Feb. 26, 2022) "“We have finalized our forecast of SC25’s amplitude,” says McIntosh. “It will be just above the historical average with a monthly smoothed sunspot number of 190 ± 20.” "“Above average” may not sound exciting, but this is in fact a sharp departure from NOAA’s official forecast of a weak solar cycle" [0] https://spaceweatherarchive.com/2022/02/25/the-termination-event-has-arrived/ https://spaceweatherarchive.com/2022/02/25/the-termination-e...
- stjohnswarts 4y agoI mean wouldn't they account for this and add thrusters and fuel to put it back where they want it?
- yabones 4y agoMaybe this will help clean up the debris from Russia's ASAT missile test last year?
- palisade 4y agoI wonder what this means for Starlink. I know that Elon put them into a slightly lower orbit accidentally than what they originally intended. Which probably had the positive side effect of better latency. But, now that solar weather is accelerating orbital decay, this perhaps affects Starlink more adversely than it would have otherwise.
- alar44 4y agoThat wouldn't affect latency in any noticable way.
- ngcc_hk 4y agoUnexpected or failed theory or failed engineering or … . What is expected in the real world? Or just an excuse. You always have unknown unknown but is this sort of expected as the sun is not yours. The solar wind model is the problem?
- mah4k4l 4y agoSure hope that Jello Biafra doesn't have his facts straight in his 1991 song The Sky Is Falling And I Want My Mummy (Falling Space Junk) with NoMeansNo. The part of the song about US orbital satellites carrrying plutonium waste with them. Please be just a little bidenism from this also so priestly character that JB is. The pitfall of the priestly archetypical character so many a time is just being out to to get the good old Holy Spirit emotional response from the churchgoers and not so much alawys concerned with getting the facts straight. Increased solar flare EMP risk during the next years ain't a picnic either. Yo this all sucks. Bummer vibes. But don't shoot the messenger. The song: https://youtube.com/watch?v=mE5ir7bJnDI https://youtube.com/watch?v=mE5ir7bJnDI
- Konohamaru 4y ago"[Solar] climate is what you expect, [solar] weather is what you get." - Mark Twain