Article re worldwide population decline

[Analytics]

5 hours ago, smac97 said:

Well, we'll see, I suppose.  You seem to think the downward spiral will correct itself at some point.  My point is that the spiral seems to be unending.  No country has pulled out of it yet.  

As a reality check, we aren't in a downward spiral, much less an unending one. The worldwide population is now 7.8 billion. Our best forecasts say it will continue growing for at least another 40 years.

In case you didn't read the NYT article to the end, it says:

And if the goal is revival, a few green shoots can be found. After expanding access to affordable child care and paid parental leave, Germany’s fertility rate recently increased to 1.54, up from 1.3 in 2006. Leipzig, which once was shrinking, is now growing again after reducing its housing stock and making itself more attractive with its smaller scale.

“Growth is a challenge, as is decline,” said Mr. Swiaczny, who is now a senior research fellow at the Federal Institute for Population Research in Germany.

Demographers warn against seeing population decline as simply a cause for alarm. Many women are having fewer children because that’s what they want. Smaller populations could lead to higher wages, more equal societies, lower carbon emissions and a higher quality of life for the smaller numbers of children who are born.

5 hours ago, smac97 said:

So we may not see a downward trend that then levels off to some sort of equilibrium.  We may instead see a downward trend that ends in the extinction of countries, ethnicities, cultures.

Extinction? You do understand that the global population is still growing, right?

If the current demographical trends in Japan were to remain constant, it will take 350 years to get down to a million people. If there were a million people in Japan, would that be the end of Japanese culture? Maybe, but such a world might also be a renaissance in Japanese culture. For example, it might give the oceans a chance to regenerate their fish populations, and the people would be able to eat as much fresh sushi out of clean oceans as they want. In such a scenario, there is every reason to believe that housing in Tokyo would be affordable and there would be a huge demand for labor. Working-aged people would earn a good living and be able to afford to have children. Further, they would have every reason to believe that their children would have bright futures, too.

Seriously. If the world was clean, housing was affordable, jobs were plentiful, and the future for children was bright, why wouldn't the fertility rate increase?

5 hours ago, smac97 said:

We could also talk about the Malthusian aspects of the policies formulated/enacted by Marx, Stalin, Mao, and so on.  

I presume you didn't add Hitler to the list because you are trying to avoid being called out on Godwin's law?

Since you brought up Marx after I quoted him as agreeing with you about Malthusianism, I wonder what you are alluding to here?

If Marx was here, he'd likely say that it's obvious why people are choosing not to have kids--it's because people can't afford to have them. That is not because we live in a poor society. Rather, the billionaires who control the media and politicians have structured society so that the people who have most of the wealth pay almost nothing in taxes, while the working class has dismal job opportunities and is drowning in debt. If we were to spread the wealth around so that the people who are actually producing society's goods and services got their fair share of the pie, then they'd be able to better afford kids.

That's what I think Marx would say, at least. What do you think the Malthusian aspects of the policies formulated by Marx are?

[rodheadlee]

On 5/24/2021 at 2:20 PM, AtlanticMike said:

Limitless solar energy from the moon!!!!! Yeah, maybe,  butt where do you get an extension cord that long? 😁

DARPA

[Stargazer]

On 5/25/2021 at 7:45 PM, Jamie said:

...only if somebody keeps launching more of those LEO satellites.  or they somehow find a way to keep them up there as long as the Lord will allow.  For now they're not designed to stay up there forever.

They would work fine until a new worldwide net got set up. 

[Jamie]

24 minutes ago, Stargazer said:

They would work fine until a new worldwide net got set up. 

Okay, just so we're clear, my understanding is that SpaceX needs to continue to launch new LEO satellites for Starlink every so often, every 3 or 4 years I think, to replace those that decayed from orbit, because each one will fall out of orbit that often.

So the Starlink system is a worldwide net that needs new satellites every 3 or 4 years, and if they can't continue to launch those satellites, the whole system will eventually crash because there won't be any new ones to replace the old ones that fell.

Maybe later yhey'll put better engines on them to keep them up there perpetually but as of now they will stay up there for only so long.

[Amulek]

17 hours ago, rodheadlee said:

DARPA

Or maybe even DHARMA !!!

 

[The Nehor]

36 minutes ago, Jamie said:

Okay, just so we're clear, my understanding is that SpaceX needs to continue to launch new LEO satellites for Starlink every so often, every 3 or 4 years I think, to replace those that decayed from orbit, because each one will fall out of orbit that often.

So the Starlink system is a worldwide net that needs new satellites every 3 or 4 years, and if they can't continue to launch those satellites, the whole system will eventually crash because there won't be any new ones to replace the old ones that fell.

Maybe later yhey'll put better engines on them to keep them up there perpetually but as of now they will stay up there for only so long.

The low orbit the satellites operate in means that the satellite inevitably has its orbit decay. You could send them up with fuel to adjust their orbit but then the launch costs more. One thing I learned when I tried to simulate "space economics" for a project I was working on was that the biggest cost in most every project is getting the stupid thing and whatever fuel you need into orbit and the fuel is often more expensive than everything else combined.

[Jamie]

6 minutes ago, The Nehor said:

The low orbit the satellites operate in means that the satellite inevitably has its orbit decay. You could send them up with fuel to adjust their orbit but then the launch costs more. One thing I learned when I tried to simulate "space economics" for a project I was working on was that the biggest cost in most every project is getting the stupid thing and whatever fuel you need into orbit and the fuel is often more expensive than everything else combined.

Seems like it would just be a lot easier to launch down into space rather than up.  

[The Nehor]

4 hours ago, Jamie said:

Seems like it would just be a lot easier to launch down into space rather than up.  

I can’t tell if you are joking.

[longview]

47 minutes ago, The Nehor said:

I can’t tell if you are joking.

I have read science articles in the past couple years of setting up permanent moon bases and mining for various minerals.  The asteroid belt could be mined too.  They are even talking about placing a space station around the moon!

ETA2:  There is a proposal for a radio telescope on the far side of the moon.

Edited May 27, 2021 by longview

[Calm]

5 hours ago, Jamie said:

Seems like it would just be a lot easier to launch down into space rather than up.  

Walked away from this once, can’t resist the second time reading it...Nehor’s unspoken question must be asked...are you joking and if not....

Please clarify what you exactly mean by this.

[rodheadlee]

7 minutes ago, Calm said:

Walked away from this once, can’t resist the second time reading it...Nehor’s unspoken question must be asked...are you joking and if not....

Please clarify what you exactly mean by this.

Mining, manufacturing and outfitting starships, satellites and power stations could all be done in space. No gravity to battle, little gravity in the asteroid mine field. 

[Calm]

4 hours ago, rodheadlee said:

Mining, manufacturing and outfitting starships, satellites and power stations could all be done in space. No gravity to battle, little gravity in the asteroid mine field. 

“Launching down into space” may mean that, but awkward way of putting it.  Still would like to know what Ahab meant.

[Jamie]

13 hours ago, The Nehor said:

I can’t tell if you are joking.

That's what a sense of humor is for.

[Stargazer]

On 5/26/2021 at 10:02 PM, Jamie said:

Okay, just so we're clear, my understanding is that SpaceX needs to continue to launch new LEO satellites for Starlink every so often, every 3 or 4 years I think, to replace those that decayed from orbit, because each one will fall out of orbit that often.

So the Starlink system is a worldwide net that needs new satellites every 3 or 4 years, and if they can't continue to launch those satellites, the whole system will eventually crash because there won't be any new ones to replace the old ones that fell.

Maybe later yhey'll put better engines on them to keep them up there perpetually but as of now they will stay up there for only so long.

I don't know for sure how long one of these satellites will last, but what I've read so far indicates an operational life of 5 to 7 years. They won't just allow them fall out of the sky on their own, though (unless a satellite malfunctions and cannot be controlled). At the end of their operational life they are deliberately deorbited. And they won't necessarily stop working in 5 to 7 years.  Most of the earliest ones have already been deorbited, but that's because they were test models, and a few were deorbited in order to test the deorbit process.  Beta testers of Starlink are reporting that even with the small number of satellites in orbit, they are getting extremely good connectivity. 

All I'm suggesting is that with Starlink out of the atmosphere, the system won't be affected by whatever happens down here, and could be used until a "Millennial level" replacement is available. 

 

[Jamie]

10 minutes ago, Stargazer said:

I don't know for sure how long one of these satellites will last, but what I've read so far indicates an operational life of 5 to 7 years. They won't just allow them fall out of the sky on their own, though (unless a satellite malfunctions and cannot be controlled). At the end of their operational life they are deliberately deorbited. And they won't necessarily stop working in 5 to 7 years.  Most of the earliest ones have already been deorbited, but that's because they were test models, and a few were deorbited in order to test the deorbit process.  Beta testers of Starlink are reporting that even with the small number of satellites in orbit, they are getting extremely good connectivity. 

All I'm suggesting is that with Starlink out of the atmosphere, the system won't be affected by whatever happens down here, and could be used until a "Millennial level" replacement is available. 

 

What I understand is that those satellites begin to fall out of the sky as soon as they are put up there, because of the pull of gravity, and they have very little control over that.  Their orbit decays at a slow rate, though, instead of just instantly falling, and they can cause them to deorbit quicker if and when they want them to fall.  It's just that because of the pull of gravity and limited engine power in the satellites to keep them up there, they will eventually fall. So even if they kept working they would still eventually fall.

[The Nehor]

The average satellite lasts about 15 years. The primary death method is not losing orbit. More often it is radiation damage eventually destroying the electronics.

Most satellites coming down aren’t dangerous. A few weeks back we had a bit of excitement when China’s boosters from a rocket launch came down in an uncontrolled descent with no way of predicting where they would land. Fortunately they hit the ocean. Sadly this is how the stupid things are designed to operate. Look up the village they wiped out in another rocket launch. Irresponsible prats.

[Stargazer]

22 hours ago, Jamie said:

What I understand is that those satellites begin to fall out of the sky as soon as they are put up there, because of the pull of gravity, and they have very little control over that.  Their orbit decays at a slow rate, though, instead of just instantly falling, and they can cause them to deorbit quicker if and when they want them to fall.  It's just that because of the pull of gravity and limited engine power in the satellites to keep them up there, they will eventually fall. So even if they kept working they would still eventually fall.

Apology, but your understanding is not accurate.

First of all, it's not the pull of gravity, per se. It's the drag imposed by the very thin atmosphere at LEO. It's a near-vacuum, but there's enough to slow the satellites down gradually.

Second, yes, of course the drag immediately begins to slow them down, but these satellites are not passive orbiters. They have onboard ion thrusters that they use to maneuver after deployment to their assigned orbits. The operational orbits of the most recent satellites seem to be in the  540 - 570 km height range. They are initially deployed at various altitudes from 300 to 570 km (seems to depend upon whether the launch has rideshare sats or not), but then they maneuver over the following few weeks to their assigned orbits, and this includes raising themselves, if necessary, to their operational orbits. They are fully capable of actively maintaining their altitude, at least until their onboard reaction mass is depleted. Which is why the operational lifetime is only five to seven years. When a given satellite has reached the end of its operational life (i.e. reaction mass for its thrusters is running out), it uses its thrusters to lower itself to a "disposal orbit", where the higher atmospheric drag will deorbit it within a year. But at the operational orbit the atmospheric drag is much less, and it would take much longer than 5 to 7 years to deorbit it. 

In other words, if not deliberately deorbited, they would continue to operate and their operational life would depend mostly upon the durability of the electronics and power system. 

[Stargazer]

15 hours ago, The Nehor said:

The average satellite lasts about 15 years. The primary death method is not losing orbit. More often it is radiation damage eventually destroying the electronics.

I'm curious about this 15 years figure. Do you have a source, or is it your own guesstimate?

Some satellites are designed to deorbit themselves actively and intentionally, others passively. And some just fall out of the sky semi-randomly.

I'd like to see an analysis about failure mode statistics on satellites. Some seem not intended to last, whereas others operate well beyond their expected capability. Hubble is still doing its job after 31 years in orbit. The two Voyager probes are still operating (at reduced capability) despite being in space, unprotected by Earth's magnetic field, for over 40 years. 

There's an area of special concern regarding radiation, and this corresponds to your mention of radiation damage: the South Atlantic Anomaly. This is an area of reduced magnetic intensity that allows the inner Van Allen radiation belt to come as close as 200 km to the earth's surface. It is known that several satellites have been "killed" by the SAA, or rather, the radiation that the SAA permits to occur at that low an altitude. The ISS is specially shielded because of it. The Hubble telescope doesn't take observations when passing through it. Astronauts have reported "phosphene" ("shooting stars") in their fields of vision when passing through it.

15 hours ago, The Nehor said:

Most satellites coming down aren’t dangerous. A few weeks back we had a bit of excitement when China’s boosters from a rocket launch came down in an uncontrolled descent with no way of predicting where they would land. Fortunately they hit the ocean. Sadly this is how the stupid things are designed to operate.

I understand that most second stage boosters are designed to safely deorbit themselves safely into the ocean after payload deployment, though China's space agency seems to be less vigilant about this. Of course, deorbiting systems sometimes fail. On 26 March 2021 a SpaceX Falcon 9 second stage burnt up over Washington and Oregon.  Its deorbit burn failed after satellite deployment three weeks before. Nothing hit the ground, or at least, nobody noticed.

15 hours ago, The Nehor said:

Look up the village they wiped out in another rocket launch. Irresponsible prats.

It's not just irresponsibility, well, maybe it is with the rocket launch. But their deliberate policies are far worse. I'm sure you've heard of the Uyghur genocide being carried out by China? What's an inadvertently wiped out village to that?

[The Nehor]

11 hours ago, Stargazer said:

It's not just irresponsibility, well, maybe it is with the rocket launch. But their deliberate policies are far worse. I'm sure you've heard of the Uyghur genocide being carried out by China? What's an inadvertently wiped out village to that?

I have. I reserve the right to point out small cruelties even if there are much larger ones.

[Stargazer]

9 hours ago, The Nehor said:

I have. I reserve the right to point out small cruelties even if there are much larger ones.

Go for it; I endorse your efforts. 

[pogi]

It looks like China has announced a 3 child policy in response to the low birth rate.

https://apple.news/Ab6nkjvMFSn6W-sEFzOWcew

[Chum]

14 minutes ago, pogi said:

It looks like China has announced a 3 child policy in response to the low birth rate.

That's a sick metric.  'Sick' in the edgy 2015 7yo sense, I mean.

[Jamie]

On 5/29/2021 at 11:08 AM, Stargazer said:

Apology, but your understanding is not accurate.

First of all, it's not the pull of gravity, per se. It's the drag imposed by the very thin atmosphere at LEO. It's a near-vacuum, but there's enough to slow the satellites down gradually.

Second, yes, of course the drag immediately begins to slow them down, but these satellites are not passive orbiters. They have onboard ion thrusters that they use to maneuver after deployment to their assigned orbits. The operational orbits of the most recent satellites seem to be in the  540 - 570 km height range. They are initially deployed at various altitudes from 300 to 570 km (seems to depend upon whether the launch has rideshare sats or not), but then they maneuver over the following few weeks to their assigned orbits, and this includes raising themselves, if necessary, to their operational orbits. They are fully capable of actively maintaining their altitude, at least until their onboard reaction mass is depleted. Which is why the operational lifetime is only five to seven years. When a given satellite has reached the end of its operational life (i.e. reaction mass for its thrusters is running out), it uses its thrusters to lower itself to a "disposal orbit", where the higher atmospheric drag will deorbit it within a year. But at the operational orbit the atmospheric drag is much less, and it would take much longer than 5 to 7 years to deorbit it. 

In other words, if not deliberately deorbited, they would continue to operate and their operational life would depend mostly upon the durability of the electronics and power system. 

Okay, that sounds like a more accurate understanding of what I understood.  Drag is a result of gravity, by my understanding, and what you call "onboard reaction mass" and described as depleting is what I was calling limited engine power.

[Stargazer]

22 hours ago, Jamie said:

Okay, that sounds like a more accurate understanding of what I understood.  Drag is a result of gravity, by my understanding, and what you call "onboard reaction mass" and described as depleting is what I was calling limited engine power.

Drag isn't caused by gravity. Drag is a retardation of velocity due to friction with material that is in contact with the skin of a spacecraft as it moves the material (e.g. atmospheric gases). It could occur entirely in deep space where there is no gravity -- for instance, the two Voyager probes are moving through space that is a vacuum better than anything we can obtain on earth, but there is still drag because there is still matter (gas molecules) out there. Negligible, but it's there. 

But I see I am indulging in my tendency to be pedantic...  

 

Edited June 2, 2021 by Stargazer

[Jamie]

34 minutes ago, Stargazer said:

Drag isn't caused by gravity. Drag is a retardation of velocity due to friction with material that is in contact with the skin of a spacecraft as it moves the material (e.g. atmospheric gases). It could occur entirely in deep space where there is no gravity -- for instance, the two Voyager probes are moving through space that is a vacuum better than anything we can obtain on earth, but there is still drag because there is still matter (gas molecules) out there. Negligible, but it's there. 

But I see I am indulging in my tendency to be pedantic...  

 

As far as I am concerned you may indulge yourself to your heart's content.  I appreciate your desire to explain more in detail.  I still think drag is an effect of gravity though because when there is anything in space that may retard the movement of something else, rather than just move when that object hits it with no retardation effect on that moving object, the reason that matter caused that retardation is because it was being affected by gravity to be where it was.  Gravity is what holds any object in its position or causes it to move within a gravitational field, by my understanding.