"Despite the challenges of distance and velocity, the receiver achieved position accuracy within 1.5 km and velocity accuracy within 2 m/s. It successfully acquired signals from four GPS satellites (L1 and L5 frequencies) and one Galileo satellite (E1-E5 bands) during a one-hour observation window. Post-landing,"
+ 44dBm GPS transmit power
-210dB path loss
+ 15dB rx antenna gain
That's slightly worse (5dB) than signal strength of a handheld device/ phone (~15dB typical handheld loss, urban environment). There is still ~15dB margin. They are cheating a little with the 15dB narrow antenna gain, which requires accurate pointing. Nice result and there is room for improvement. Note: -210dB = 10^-21
Stars. Finding Earth is a necessarily solved problem for E-L communication.
Why?
Lunar night means that the Sun has set - but the Earth remains in the sky in the same position.
They used Qascom QN400 receiver.
And there is a Qascom company profile: https://italianspaceindustry.it/listing/qascom/
[0] - https://en.wikipedia.org/wiki/Lunar_orbit#Perturbation_effec...
Another option might be a LORAN style system put up on towers. With lower gravity and no atmosphere I imagine we could stick transmitters up very high without super complex construction, maybe even just a giant carbon fiber tube with a transmitter at the top.
I had no idea the moon was that lumpy. The wiki entry says that despite the mascons there are 4 known stable orbital inclinations?
https://web.archive.org/web/20210307002503/https://science.n...
And they're very lumpy.
> The mascons' gravitational anomaly is so great—half a percent—that it actually would be measurable to astronauts on the lunar surface. "If you were standing at the edge of one of the maria, a plumb bob would hang about a third of a degree off vertical, pointing toward the mascon," Konopliv says. Moreover, an astronaut in full spacesuit and life-support gear whose lunar weight was exactly 50 pounds at the edge of the mascon would weigh 50 pounds and 4 ounces when standing in the mascon's center.
> and the two stable Lagrange points, L4 and L5
We have plenty of spacecraft hanging out around L1, etc. It's possible to orbit it without too much issue. Having one broadcast a navigation signal synchronized with GPS would not be too bad.
> are as far from the moon as Earth is
The issue isn't that they're far away-- it's that they're all in pretty much the same direction. There's very small uncertainties in orbits and measured path length, but if they're all in the same direction you get very poor lateral position.
This is the same effect you can get if you can only see a little tiny bit of the sky with GPS. You might have enough satellites to navigate, but since they're all close to the same direction the navigation solution is much worse.
https://www.sstl.co.uk/what-we-do/lunar-mission-services
QUOTE: A constellation of interconnected lunar orbiters will enable surface missions operating on the far side of the Moon, without direct to Earth line of sight, to keep constant contact with Earth. It will also provide lunar navigation signals to support critical mission phases such as precision landing of scientific equipment and the operation of rovers. In addition to communication services, the Lunar Pathfinder spacecraft has been selected by ESA and NASA to host a number of experimental payloads:
An ESA GNSS receiver capable of detecting weak signals coming from the Earth GNSS infrastructure (GPS and Galileo), demonstrating its potential role into Lunar navigation
A NASA retro-reflector to demonstrate laser ranging capabilities
An ESA radiation monitor to study orbital radiation conditions
Acting both as technology and service demonstrator, Lunar Pathfinder is the opportunity for scientific and commercial mission developers to support the development, test and standardisation of Lunar communication infrastructure, and for emerging off-planet telcos to acquire experience of lunar asset operations and off-planet service delivery.
Lunar Pathfinder is due to operate in an Elliptical Lunar Frozen Orbit (ELFO) for an operational lifetime of 8 years. The spacecraft can operate 2 simultaneous channels of communication with lunar assets: 1 in S-band and 1 in UHF. Performance, such as coverage and data-rate, depend both on the relative position of the user asset to Pathfinder at the moment of the connection, as well as the capabilities of the communication module onboard the user asset. Once safely retrieved onboard Lunar Pathfinder, communications are relayed back to Earth ground stations in X-band.I do wonder though with computers and cameras and celestial navigation, why that is not used vs GPS on the moon
Ussally enhancing an existing technology that is widely deployed and understood to fit a new situation is better than inventing something wholly new (though not always)
Celestial navigation works on the Earth's surface (or the Moon's surface), because being able to determine the orientation of the local horizon (or zenith) is equivalent to determining your latitude and longitude. But that doesn't work for a spacecraft that doesn't have a horizon reference.
Of course, if you're orbiting the moon and you can accurately observe the directions to landmarks such as mountains and craters, you can fix your position relative to them. But that's not really what you'd call "celestial navigation".
I assume you would need orbital ephemeris info much like we need for GPS satellites.
But, given measurements of angles to multiple planets, how well could you estimate your position? Would there a lot of error for your normal vector to the earth's ecliptic plane?
> Sextants can be read accurately to within 0.1 arcminutes, so the observer's position can be determined within (theoretically) 0.1 nautical miles (185.2 meters, or about 203 yards). Most ocean navigators, measuring from a moving platform under fair conditions, can achieve a practical accuracy of approximately 1.5 nautical miles (2.8 km)
Some napkin math, assuming using a Sextant to achieve similar accuracy of 0.1 arcminutes on the Moon, because Moon is about 3.7 times smaller than Earth, that 0.1 arcminutes is around 50 meters on the Moon. One can expect extremely clear sky and certainly not riding waves on the Moon, so the practical accuracy should be close.
[0] https://theaviationgeekclub.com/the-sr-71-astroinertial-navi...
a kilometer-or-so is about what you get on Earth without a lot of sophisticated corrections, averaging, and kinematics. So, if they're not doing all that stuff, they could be doing quite well. (on the other hand, one of the bigger correction terms-- the ionospheric delay -- they don't have to deal with-- but they have to deal with all of their measurements being in "one direction"). If e.g. they don't know about the moon's relative motion, that's a big disadvantage.
If, on the other hand, they get the kilometer after a -loooot- of averaging, that's quite bad.
I don't know how big of a fleet you need to make this worthwhile, though. Just one satellite in a different direction would collapse that big error ellipse to a much shorter arc.
However, building out a ground system using towers on the moon would work. With the low gravity of the moon and no wind, you could build pretty tall structures with beacons for positioning. You'd need line of sight so it would be costly to build out this system across the entire surface.
A 1km tall tower built every 58km would give you similar positioning as GPS (three intersecting circles). But also, the moon is not terribly interesting so the few long trips that would put you far from base wouldn't require instant positioning. A star tracker and an hour of watching GNSS would work just fine. If there ever was a significant population on the moon, they'd have the lunar equivalent of busses (traveling over marked paths) or light rail to get them in-between facilities.
Building a network of a very tall tower every 58km around a globe of the Moon seems very uneconomic.
That has been planned for awhile as part of Artemis.
7.2 kph; 4.5 mph.
You mean 7.2 km/h.
Thanks for the conversion, though!
In Europe, kph is non existent, and I felt that it’s bizarre to convert like that.
What I don't know is: Even when receiving a good signal... how difficult would be calculating location when satellites are going to be all concentrated in a really small portion of the sky, and all of them in a proportionally small distance between them, compared to the distance of the receptor?
I wish they had said in the article what the accuracy is!
The satellites are 20 Mm high above the ground so their spread is 53 Mm, which is 4.4 times the diameter of the Earth (12 Mm). So yes, the angular size of the satellite cloud (7.896°) is quite a bit larger than the Earth (1.785°) from the moon PoV.
- Orbit height: 20,200 km
- Earths diameter: 12,760 km
Just pointing out that the typical "GPS" accuracy we're used to seeing isn't happening with only 4 satellites in view.
At geo the commercial satellite I worked with had position accuracy within about ten meters, and we always had access to 6-8 GPS satellites at a time. Obviously at the moon the signal is much fainter but my understanding is that it's essentially the same just harder to detect
So you could treat that as a virtual satellite in the other direction.
I also know that NASA has experimented for years with satellites (even all the way up in GSO) using GPS signals for position-finding, so this is further out but not unprecedented work.
Apart from the attenuation from distance, I would expect that the navigation sallellites point their antennas mostly downwards to earth, but you might find some that radiate outwards. I don't think you can expect to receive from half the satellites though.
1: On Earth we account for that by using ground stations to track the satellite locations, with the ground station locations determined very very precisely using non-GPS techniques (old school surveying techniques). On Mars, that's not going to be possible until we get a lot more done, probably a later human mission would be the first time that could be done.
And, the atmosphere? What atmosphere? It's negligible compared to Earth. Got to be down the list of important variables.
We can send a mission to Mars and arrive within a few meters of desired orbit, but it's going to be hard to figure out where a satellite is? My doubt-meter is hitting the pin.
NASA is very good at sending spacecraft through regular space and hitting precise windows (MCO units issues aside), it's in orbit that things get more complicated, because now there are just a lot more potential interactions to deal with. We can use LOS on planetary occultations to give you some data, but it's still a lot of work to get from there to mascon maps, upper atmospheric data, etc.
A system like GPS? Probably never. It would be fantastically expensive and solve a problem that no one has. In any case, the moons would be a poor choice for signal transmitters: 1. landers are harder than satellites 2. two moons is not enough for a system like GPS 3. three-body problems mean that we can't really know the future configurations of the system with high precision on anything but the very short scale.
In any case, it costs something like $700 million per year to operate the GPS system here on Earth.
And even three orbiters would give you a better fix than none.
I think the naysayers are reaching, to argue against GPS transmitters around Mars. It seems inevitable.
Once we have tens of Starships of annual transport between Earth and Mars such that putting about a dozen satellites in Mars orbits every decade or so [1] is cost effective.
Using Elon math that’s the 2030s. Ignoring his mortality-driven forecasts, probably the 2050s.
They competition would be balloons, which can be made from indigenous polyethylene [2], floated above a settlement with a loud radio. You’d have range and direction home, which should be good enough for decades, potentially into the 2100s when, on a very optimistic schedule, inter-settlement transfer begins to become common.
[1] https://www.esa.int/ESA_Multimedia/Images/2023/06/Satnav_fro...
I guess technically they could use latitude and longitude projected all the way out to the moon, but that would be pretty hard to use.
Would it be possible to use celestial navigation to obtain a more precise location?
For the moon, it depends on many factors that differ from Earth. The radio towers' structures probably need less material, at least.
On the other hand, as we get closer to colonize other planets, or at least try to plan for this end, I get depressed more and more.
We're enough burden for a single planet, and definitely too much for a solar system.
Honestly, no, I don't want more humans around.
Except that we are measurably living in a mass extinction. Most species are dying, except for us (at the moment). So I disagree: we make the conditions worse for all species.
The climate change that we are measuring now is happening a lot faster than the one that got the dinosaurs (and most big animals) extinct. 96% of animals on Earth are cattle, living in the conditions we know. I am not sure we can say "we don't have any impact on other species".
That's your deduction. We should correlate the "dying" to other times in the last millions/billions of years where the temperature rose tis "quickly".
I really feel humans think they change way more than they do.
They’re doing a bad job of arguing a good point. Let me try.
We are objectively in a mass-extinction event [1].The sixth or seventh in our planet’s billion-plus year history of life. Its most-intense phase lines up with industrialisation [2].
That said, we obviously don’t make life worse for all species. Cattle, cats, dogs, pigeons, rodents, roaches, influenza et cetera are doing quite well with humans.
I live in ranch country. Cattle do fine. They’re wild animals that live much like the bison, on the same land as the bison, except they get food and medicine and don’t have to worry about predators tearing them apart alive. In exchange, we kill them relatively young (though not that young risk adjusted), and that varies from place to place. (Dairies are more industrialised.)
We certainly would if we found evidence of any similar events in the past. Do you have contradictory info?
> As the Earth moved out of ice ages over the past million years, the global temperature rose a total of 4 to 7 degrees Celsius over about 5,000 years. In the past century alone, the temperature has climbed 0.7 degrees Celsius, roughly ten times faster than the average rate of ice-age-recovery warming.
> Models predict that Earth will warm between 2 and 6 degrees Celsius in the next century. When global warming has happened at various times in the past two million years, it has taken the planet about 5,000 years to warm 5 degrees. The predicted rate of warming for the next century is at least 20 times faster. This rate of change is extremely unusual.
https://earthobservatory.nasa.gov/features/GlobalWarming/pag...
> The findings also reveal that the Earth's current global temperature of 59 degrees Fahrenheit is cooler than Earth has been over much of the Phanerozoic. But greenhouse gas emissions from human-caused climate change are currently warming the planet at a much faster rate than even the fastest warming events of the Phanerozoic, the researchers say. That speed of warming puts species and ecosystems around the world at risk and is causing a rapid rise in sea level. Some other episodes of rapid climate change during the Phanerozoic have sparked mass extinctions.
https://news.arizona.edu/news/study-over-nearly-half-billion...
It's not.
> I really feel humans think they change way more than they do.
In 2025 this is either extremely uninformed or super dumb. Start reading, maybe.
I do understand that this is a sensitive subject to some, so I apologize for any distress I seem to have caused.
There are things where the scientific consensus is so big that even if you "disagree" with it (whatever that means), you have to assume that you are wrong until you prove you aren't.
Maybe gravity doesn't exist, maybe we live in the Matrix. But for all intents and purposes, gravity does exist. If you disagree, you're wrong unless you come with evidence that shakes the scientific consensus. I mean evidence, not a mere belief that maybe gravity doesn't exist because you've read it somewhere.
If you don't believe that we humans are the cause of the biodiversity loss and climate change, today, you're wrong. And if you can't recognise that... well join a Flat Earther convention and have fun there, I don't have time for this here.
I read his comment as an admission that nature is currently too wonderful and complicated for us to understand or control, not an assertion that global warming isn’t real or whatever you think he said.
Humans created global warming and mass extinctions and it seems like the best way to stop it is to get more smart and dedicated humans, which aren’t rare but are uncommon. You better start hoping we pop out more people
If humans created global warming, a very likely scenario is that more humans just means more warming. I'd argue that's a saner default assumption.
Mass extinctions are not a human creation. They're natural events, like the plague.
You’re ignoring the energy intensity of GDP and lifestyle intensity per capita, each of which varying within historic ranges flips your outcome across zero. Add to that the largest emitters facing declining populations before immigration and I’m not sure what your point is.
It's not an assumption, it's the only option. Unless you think extreme and nonsensical ideas like population restrictions or voluntary extinction are viable (as in, people will go along with it and it will actually work), people have to come up with a way to stop climate change. The fucking elephants aren't going to do it.
My point with the "mass extinction aren't a human event" comment is that the Earth does not privilege us in the slightest. Exponential growth is not natural. Extinction events are natural.
Entirely agree! I don't want to give the impression I'm assuming we're doomed. I'm not. I'd put true of a true existential threat to humanity at near zero. However, I'd put the probability of a major impact to our current standard of living to be somewhat higher, where my kids and grandkids are forced to live very different lives than my own. Maybe WWIII, maybe just mass migrations, maybe we see a few nukes go off. These are all very possible futures. Far from certain, but also far from impossible.
In the face of this, I'm not discouraged. I think we should do what we can to protect ourselves against such threats, and I think we've been doing a pretty good job! But I also think we should not be entirely surprised when faced with drastic shifts in birthrates and geopolitics. We're no longer in an era where infinite growth seems sustainable, and people and nations are starting to realize this.
Not at all, but that's the thing: it's very difficult to have a discussion with people who reason like you. Because you can believe something does not make it right. Saying "my sources are different" is just a way to justify your beliefs. "Well, I believe in some people, you believe in others, that makes us equal". That's how people like Trump get elected. He keeps saying everything and its contrary, and people just believe in him. Where all the facts suggest that he is a dangerous (yet charismatic) moron.
The scientific way to approach it is this: "There is a large consensus about X. I don't know much about X, so I could believe Y and Z. I want to get informed, so I need to read and understand X (not Y and Z, not yet). Once I do understand X, I can start to question it by reading about Y and Z". You'll find that usually, after you have some reasonable understanding of this large consensus, Y and Z usually are at least less consistent, usually vague, generally believed by people who don't have much knowledge about X.
I am not saying that you need to have 3 postdocs in X to give an opinion. But you have to make the difference between scientific consensus and beliefs. And if you want to change the scientific consensus, you have to be pretty damn well informed, you can't just repeat Y and Z because you read it on some social network.
Now I get your next answer: I'm just a nobody on the Internet, why would you believe me instead of Trump? But again, I don't need you to trust me. I need you to do your due diligence and read about the scientific consensus before you feel entitled to say "my opinion is worth just as much as yours". And now you say: "and why do you think you're right?". I studied environmental chemistry, and I can tell you that the consensus is goddamn consistent, whereas the climate denier claims are systematically uninformed.
> I really feel humans think they change way more than they do.
Which was a response to me saying that humans make the conditions worse for all species.
It is literally denial of our responsibility in the climate change and current mass extinction. The author of that comment also said: "Let me be clear: the climate IS changing, I just doubt that it's mostly caused, or potentially solved by, human behavior", which is explicit denial. You came to defend that point by saying "Ah, the classic “Anyone smart thinks exactly like I do, so you must be dumb"".
So my answer is explaining to you how I don't think this is the classic "anyone smart thinks exactly like I do so you must be dumb".
Maybe you are not clear with the position you were defending?
Oh, I didn’t see that comment, he made it lower down. I disagree with that. But I wasn’t defending that, I was replying to his original comment, which was completely reasonable
However, you didn’t address my main question: how can we be a burden to a red wasteland?
Ah, at worst, all humanity will go extinct. Which doesn't matter much at the grand scale. It'll be exciting for the next ones, if the planet is left in a state to allow another such evolution, or somebody else likes the colors and wants to visit for a couple of revolutions around the Sol.
> how can we be a burden to a red wasteland?
We are not sure that it's a red wasteland. We think that life has a single foundation and will evolve from that one.
Maybe it had a similar ecosystem before, and tons of bacteria are in hiatus. Maybe there's something else underground. Maybe there are other living organisms which we can't detect.
I don't think that Mars has worms which might eat us for snacks and giggles, but I'm not sure that it's devoid of life completely, either.
Absence of evidence is not evidence of absence.
To be honest, I don't care so much about humanity going extinct in 500 years. But somehow I care about me or my children dying at an early age because we as a species don't manage to not screw up our lives.
The only near-term total human extinction risks are cosmological. We don’t have the ability to wipe ourselves out with even nukes, just wipe out modern civilisation. (And that would require someone going out of their way to nuke e.g. Oceania and South America.)
Fun fact: that climate change was a lot slower than the one we are measuring now. A lot.
Dinosaurs couldn’t construct shelter with A/C, harvest power from the sun and the earth’s core or move around the planet in a day [1]. And even then, it took at least tens of thousands of years [2].
It’s about as unscientific to claim anthropogenic climate change is going to cause human extinction within even 10,000 years as it is to claim it doesn’t exist.
[1] source needed
[2] https://www.reuters.com/article/lifestyle/science/asteroid-m...
Simple question: do you know what we humans eat? Can you grow that in your bunker at scale?
And even if you could: if your project is to make the Earth look like mars and call it a success because some humans survive when most species are extinct, then I don't know what to say.
> It’s about as unscientific to claim anthropogenic climate change is going to cause human extinction within even 10,000 years as it is to claim it doesn’t exist.
This is called manipulation. I didn't say that. What I said is that for what we know and measure, climate change is likely to cause a global collapse, maybe human extinction.
Claiming that climate change doesn't exist is just wrong.
Soil, artificial UV and nitrogen extraction from air are solved problems. And you would not need a bunker, just A/C (or filtration if we’re going nuclear).
> because some humans survive when most species are extinct
If you’re talking about climate change, it’s some humans and some species are extinct. (Most cuddly wild mammals and birds we like.)
> for what we know and measure, climate change is likely to cause a global collapse, maybe human extinction
Right. This is false catastrophism. There isn’t a “maybe” human extinction within known parameters. There isn’t even an end to industrial civilisation without nukes.
People say this crap and undermine the entire climate movement because when the lie in extinction risk is shown it brings into legitimate question the other claims.
What the hell? Let's completely put climate change and mass extinction (which are huge problems on their own) aside for a moment.
Do you know what threatens the collapse of the industrial civilisation? The end of fossil fuels. That's a very real problem right here right now. Without the climate change and mass extinction problems, that would still be a reason for our industrial civilisation to collapse soon.
Luckily, the solution to all of those 3 problems is the same: cut down emissions, do less with less. A good introduction to the problem, I find, is here: https://www.amazon.com/World-Without-End-Illustrated-Climate...
…we have other power sources.
No science supports your assertions. The single source you’ve put forward, World Without End, doesn’t support your assertions.
We aren’t going extinct because of climate change. We aren’t losing industrial civilisation because of climate change or running out of fossil fuels.
There are good reasons to act on climate change without lying. And by lying, you undermine the legitimate science around the damage and costs.
Clearly you haven't read it, have you?
I couldn't care less about mars, to be honest. My problem is that some use it as (an absurd) justification to commoditise space. SpaceX is hurting the climate by making it cheap to send lots of rockets.
You want to say "oh, actually, we've seen that 99% of our emissions was due to our production of trackpads, so the solution is to stop using trackpads and all is well"? Let me tell you that the problem is a lot harder than that. We need to work on everything everywhere.
But same here: we have enough problems trying to survive on Earth, we should focus our great talents on that.
> as we get closer to colonize other planets
We won't colonise mars, and we definitely won't go further than the solar system. Just look at the distances, it's completely absurd.
BTW, "because I don't know means that I'm not wrong" is dumb, and dangerous.
Let me be clear: the climate IS changing, I just doubt that it's mostly caused, or potentially solved by, human behavior.
It's a great way to sell some solar panels, though.
EDIT: also, let me be clear (because I know how your brain works): I love that we're getting cleaner air. I love that we find alternative sources of energy. That's all amazing! But I predict there's never a "finish line". We'll never do good enough, and our kids will always die. Or our kids' kids. I'm not affected by that thought anymore.
Yep, climate denier. You put your belief before the scientific consensus. You may as well believe that the Earth is flat, it would not be less valid than your current position. Except that your kids won't die because of the Flat Earthers, probably.
> It's a great way to sell some solar panels, though.
Sure, many people try to sell their shit pretending it is "green". Tesla comes to mind (or Tesla before it became the nazi brand, I don't know nowadays).
> We'll never do good enough, and our kids will always die.
Well your kids will probably live in wars, global instability and die because of the climate change. Sure, they would eventually die anyway. Keep what you are saying now in mind, for when you'll have the discussion with your kids in a couple decades. Remember to tell them "we're living in a shit world, uh? Back in the days, I was one of those people who proudly didn't care. Enjoy now."
Why do you feel we can't colonize Mars? Or perhaps any of the asteroids? Perhaps not in this century but do you feel it'll never happen?
Depends on what you call "colonising". We may be able to send a few humans there, just for the sake of doing something super costly and completely useless. We as a species won't independently survive there.
We, as a species, are on the verge of collapsing on Earth, which has all the conditions needed for life. We literally are failing to survive on Earth. Why the hell would we put resources into sending a few people to mars?
> Perhaps not in this century but do you feel it'll never happen?
The way we are going now, long before next century we will be in a place where a large portion of Earth (around the equator) is unlivable. As in, without life support we won't be able to survive outside. It's cute to think about colonising other planets, but at some point we should have priorities.
Humanity is not on the verge of collapsing on Earth. Not even close. There is billions of us and our number is going up. Even with the worts climate change predictions the threat is not that we will all die, but that some of the places where we live now becomes uninhabitable and that our descendants will have a worse time living in the future.
> We literally are failing to survive on Earth.
That's literally not true.
You don't understand the meaning of "collapse", do you?
Second, you talk about "the worst climate change predictions". That's completely absurd. Quite obviously "the worst climate change prediction" implies that we all die.
Finally, you say "some of the places where we live now becomes uninhabitable and that our descendants will have a worse time living in the future". Not sure if you are aware of that problem or if you are just mentioning it because you quickly read it here. If we reach 4 degrees of warming (and that's a prediction if we don't change anything, knowing that we have already passed 1.5 earlier than expected), a large part of Earth around the equator will become unlivable (not as in "there is no more food, you have to import" but as in "you can't survive outside without life support).
We're talking billions of people. What happens when half of the population of the planet has to relocate while the other half has issue growing food (because of course, the rest of the Earth is also impacted), do you think?
That's wars, global instability, lots and lots of deaths, and the end of society as we know it. That's collapsing.
If you understand "prediction" to mean "any bullshit made up by anyone" then yes. But if you mean by "prediction" what we think is likely to happen based on available data and knowledge then not.
> Not sure if you are aware of that problem or if you are just mentioning it because you quickly read it here.
I'm aware of the problem. That is why I wrote what I wrote.
> If we reach 4 degrees of warming (and that's a prediction if we don't change anything, knowing that we have already passed 1.5 earlier than expected), a large part of Earth around the equator will become unlivable
Correct. And that is really, really, really bad. So bad that we don't have to overstate how bad it is.
> That's wars, global instability, lots and lots of deaths, and the end of society as we know it. That's collapsing.
That's societal collapse. That's really really bad. But you were talking about species level collapse. Let me quote you "We literally are failing to survive on Earth." That's not the case. We don't have to overstate our case. Extinction is not the danger we are facing here. It is continued living on the species level in a much more precarious, dangerous, unpleasant way. It's failing to thrive, not failing to survive.
I don't have to go that far, really! The IPCC models are systematically observed to be optimistic. 4 degrees is not particularly pessimistic.
> That's societal collapse. That's really really bad. But you were talking about species level collapse.
Even nitpicking here doesn't work. If you lose 90% of your population, as a species, it's collapsing.
I understand the point you are trying to make: "it's not clear that the humans species will disappear, just most humans". And I'm not saying it's clear. I'm saying it is a risk. Because we are not wild animals. Most humans, if you don't give them prepared food in a plastic bag, can't survive. And we're talking about surviving in a much harder world (4 degrees means that growing crop is harder in many ways).
But again it is a moot point. What's the point of going around saying "Guys don't be scared, we won't disappear as a species. Most of us here will die, still, but that's not as bad".
Now, let me address your nitpick: We as a society are on the verge of collapsing, and we as a species as well. With a non-zero risk that the entire species will go extinct.
The point is to be accurate.
> Guys don't be scared,
I didn’t say to not be scared. There is such a thing as surviving something, but wishing that you didn’t.
> Now, let me address your nitpick
You said we are about to go extinct. I think we are not. If that is a nitpick i don’t know what is material disagreement.
You want to be accurate, please also be when it doesn't work in your favour. Let me quote what I said:
> We, as a species, are on the verge of collapsing on Earth
I said "on the verge of collapsing", not "about to go extinct".
Again, I would argue that we are, right now, building the conditions of a collapse, meaning that many (most?) humans may not survive it. It's not just climate change, it's essentially all the planet's limits we know. Did you know that we have probably already lost the Amazon?
But well, what's the point of arguing, you agree that it's really, really, really bad. Sorry if you don't like my wording, I'll try to do better next time ;-).
The main reason, however, is that humans can't co-operate on a scale that would be needed to do it. World events show it clearly right now.
This is not the age of colonial exploration where a small band of Europeans use their weapons to overpower the natives and grab their resources and take their fertile land. This is deciding to live in the middle of a frozen desert where there is nothing.