Is 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."
Yes, 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.
I 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.
Sidenote: KSP is the worst way to build intuition in this particular case as it doesn't have any drag model in orbit, or even n-body simulation, so no orbital decay is possible there. Playing around with NASA's GMAT [0] or similar more comprehensive software is much more helpful to understand real-world orbital mechanics.
It'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.
Plummet implies a straight-line dead fall, or close to it. It derives from lead weights (hence the similarity to "plumber") attached to a line, used for sounding depth of water or for marking a straight vertical line. The "verbing" of that noun and its figurative use to describe falling appear to be quite recent developments—Webster's 1913 only lists a noun. I'd say it's the wrong word for this case, but then I'm an opponent of using slightly-similar words interchangeably, such that we effectively have fewer words to work with. However, I'm losing that fight anyway, so who cares I guess.
[EDIT] On reflection, this is even goofier than I thought at first, since the choice of lead for those applications is precisely because it's little affected by wind, and even fares better than most things against moving water, while this is entirely about something falling faster because of its interaction with air.
I don't see why it is a dumb objection. Word choice is important, especially for journalists trying to convey information to the general public and even more so when it comes to headlines - as the majority of people won't read the article to understand the nuance.
I genuinely think a decent number of people are going to envision a situation where satellites suddenly plunging out of orbit like they would in some big budget disaster movie. You are well within your right to tell them they are thinking of the word "plummeting" incorrectly but you are fighting an uphill battle. Technical and dictionary correctness has its place but to convey information properly people must consider the vernacular.
It’s dumb because it is based on the objector imagining what an uninformed reader would imagine and thinking that anything unlike mighty Thor smiting satellites out of the sky with lightning bolts would make the word “plummet” inappropriate.
Satellites are falling relatively very fast compared to usual and some of them have or soon will burn up in atmosphere as a result, it’s a headline, not a half sentence expected to grant a degree in astrodynamics.
Likewise, why would you imagine that an uninformed reader would see the word "plummet" and understand that none of these satellites are in immediate danger of re-entry, that they will in-fact continue to stay aloft for several more months, and that in this context plummet means an orbit decaying an order of magnitude faster than expected?
You are correct, one of the meanings of plummet is a rapid descent. These satellites are rapidly descending. You are correct.
Again, though, word choice matters. Can you see where other commenters and I are coming from?
Remember that Star Trek movie trailer wherein the Enterprise (or a similar) spacecraft seemed to drop like the string had been cut? That's what I picture with "plummet".
There 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.
Just 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
It'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.
We 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.
> 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.
Yeah, 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.
Well 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?
While 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).
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.
I'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.
They 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.
For 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.
Even 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.
10 million USD is an acceptable loss at that scale against other tradeoffs. Launch costs are low, so plus these sats aren't as expensively made because their supremacy (meaning their height off the ground here, that's my intent with that word) does not cost their weight in gold.
Same as Tesla crashes versus speed versus manufacturing cost, versus everything, tradeoffs. Are they justified or not?
Was this one disappointing? Maybe if you're going by the title alone, which granted was the original question. However, it was a decent enough explanation for the target audience of the site.
But 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.
