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Comment by Retric | Hacker News Reader

> self-defending orbital satellite and space faring vehicles providing economic resources back to nations on earth.

Step away from the science fiction for a while, we don’t have forcefields and aren’t getting them anytime soon. Satellites have few realistic ways to protect themselves from Kessler syndrome let alone any serious attacks by nation states.

Best bet is to stay in low enough that the atmosphere provides some protection, but that line gets blurry between satellites and aircraft.

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You're missing it. Without a communications link, satellites and space vehicles cease to exist. The only value they provide is via wireless signal links back to us. All space problems are communications security problems of confidentiality, integrity, and most importantly, availability. Denial and disruption of space communications is the threat to all vehicles. Interception reaps any benfit they provide back without the investment in sending them out there. The only sovereignty we have in an age of space economics and risk comes from cryptography.

What, did you think our plan was to spend all this money just to figure out a way to bash them together? Like, rocks?

Nah. It's easy to envision fully autonomous vessels in space which function fine without a communications link. In fact, that's probably the most desirable type of craft, one that isn't hampered by delays in communication and can respond quickly to dynamic situations.

https://www.af.mil/About-Us/Fact-Sheets/Display/Article/1045...

It really depends what's the purpose of the satellite.

I think the assumption here is that most of the added value of having a satellite in the first place is through the services it delivers through the communication link (imagery, communication relay, ...)

But how can you ensure that it is operating in an autonomous fashion for you as opposed to someone else who has commandeered it whether through physical force cyber means?

So your hypothetical adversary is getting physical access to satellites in orbit to remotely disassemble them and then put them back together after swapping hardware.

How exactly do you think this is remotely cost effective? Really the best defense is to spend less than 1/10th as much and launch a new satellite.

OP was describing a future where resources are being mined in space and returned to earth,. That is a future where people will have the means to build industrial capacity beyond the orbit of earth which means that infrastructure could be contracted out for surreptitious proposes.

All it takes is one rogue self replicating asteroid miner...

Asteroid mining in 50 years is also the least realistic thing he said. 50 years ago we had already been to the moon, and now people are talking about the possibility that we might at some point go back a few years from now.

Now you want to add self replicating robots on that timescale... Why not time travel and FTL while you’re at it.

Have you been paying attention to what SpaceX is doing with Starship?

Things are developing far faster than you think.

https://www.afrl.af.mil/News/Article/3002762/space-security-...

Which is somehow different than protecting a random website because it’s in space space space.

Or wait no it's not.

I think you're overstating the importance of satellites. GPS is probably the only useful satellite for the majority of the world, and it is an unencrypted, one-way signal.

Let's split this into military, and non military use.

Non military is GPS sure, but also weather, communications and entertainment. As well as a bunch of internet, a segment that is likely to grow a lot in the near future.

So, non-militarily it's likely that average Joe makes direct use of satilite tech multiple times per day for different reasons.

For the military there's also GPS, communications and reconnaissance. All key features of any mission.

So yeah, these things are super important. Now whether this means a "space force" I'd needed or not is debatable. I'd say not, it seems to me this is a computer issue not a location issue. Attacks on these resources are likely to be cyber in nature, not physical. Physically harming satillites pollutes the area for all players. On the other hand taking control of a working satilite delivers huge gains for basically no construction or launch costs.

Again I think you're overstating their importance. Less people are using satellite TV everyday thanks to streaming. Satellite internet is such a miniscule percentage of internet use it might as well be a rounding error. I don't doubt that will change but it will always be a fraction of the market.

As far as military goes, the US armed forces are insanely overpowered. None of that has to do with satellites. There could be a solar flare that knocks out every electronic device and we would still be on top.

It is also highly unlikely the US will ever officially be at war again. Congress would get eaten alive by their constituents. The military exists purely as a show of force, and a means of siphoning away taxpayer money forever.

>>>As far as military goes, the US armed forces are insanely overpowered. None of that has to do with satellites. There could be a solar flare that knocks out every electronic device and we would still be on top.

In order to be "on top" we have to be able to project power outside of our borders....borders which happen to be REALLY far from any credible challengers. Our overmatch comes from a well-drilled combination of prolific intelligence collections, robust communications, and precise and timely targeting (including having sufficient information to NOT target friendly forces by accident). ALL of those abilities are heavily reliant on satellites.

Accurate imagery of adversary forces staging equipment for attacks? Those pictures come from satellites. Near-instant awareness every time a ballistic missile launches? Those are detected by infrared sensors on satellites ( https://en.wikipedia.org/wiki/Space-Based_Infrared_System ). Global awareness of where friendly troops are, down to the meter? They are taking GPS-based location data for their positions and sharing it via satellites ( https://asc.army.mil/web/portfolio-item/c3t-jbc-p/ ) ( https://www.iridium.com/products/nal-research-shout-nano-per... ). Need to pass orders and tasking messages to subordinates at geographically-distant, austere locations? Yup....satcom ( https://www.globalsecurity.org/space/systems/fleet_ops.htm ) Long-range terrestrial radio, for example HF skywave, is less reliable, has a low data rate, and presents a VERY large target for any adversary competent at electronic warfare .....which is both the Russians and the Chinese).

Purely show of force, huh? Must be a fairly recent development.

I thought this "end of history" narrative would be dead by now. It's incredibly naive to think that major wars are a thing of the past. The trade/commerce argument against the political viability of war has been made and debunked in the past. WWI should have been the nail in that coffin but I guess the idea is too appealing to give up.

> In The Great Illusion, Angell's primary thesis was, in the words of historian James Joll, that "the economic cost of war was so great that no one could possibly hope to gain by starting a war the consequences of which would be so disastrous."[4] For that reason, a general European war was very unlikely to start, and if it did, it would not last long.

Published in 1909. Yeah..

Countries have largely stopped declaring war even when they send troops to overthrow a county. It's the kind of distiction the only matters in international politics.

To underscore how silly this is the last time the US “declared” war was 1942. https://en.wikipedia.org/wiki/Declaration_of_war_by_the_Unit...

Well if that was throwntoday's point, it's a distinction without a difference. The Korean War particularly, despite not being officially declared as a war, came disturbingly close to going nuclear.

China has already threatened to shoot SpaceX's starlink out of the sky because it poses a NatSec risk to them by puncturing their Great Firewall.

While GPS is hugely important - no debate there -, there are quickly growing alternative uses for satellites. Also, satellites are already used a lot more in business than people realize [2]. Walmart, for example, used to own the largest fleet of satellites in order to connect their stores to HQ before communication was ubiquitous. It built it out in the 80s.

[1] https://www.engadget.com/china-military-scientists-anti-star...

[2] (scroll to 1987) https://corporate.walmart.com/about/history

> GPS is probably the only useful satellite for the majority of the world,

Synthetic aperture radar is incredibly useful to the military [and generally.]

A weather satellite provides economically important information. That's a resource. We have those today and meteorology has been critical to naval operations for essentially all of human history.

We don't need science fiction. We already exist in a world where effective anti-satellite weaponry threatens economic and military power.

“self-defending orbital satellite”

That's what I was objecting to.

It’s actually quite easy for a satellite to defend itself. It just needs delta v or a lot of energy for a directed energy weapon.

It takes a big rocket and lots of time to hit something in geosynchronous orbit. If the satellite has been refueled, it’s delta v capability would dwarf any potential impactors. Otherwise it’s going to be 30+ minutes for a potential impactor to reach the satellite, why not shoot a laser at it for that time period?

Because your adversary could send a bunch of tiny objects in the opposite orbit that impact at around Mach 40.

You can for example destroy every single satellite in geostationary orbit by launching 1 payload of junk going the wrong way. Worse this isn't recoverable geostationary orbit is simply useless on the scale of hundreds of years. Dodging with delta V becomes a continuous problem you can at best simulate geostationary orbit with constant acceleration.

Geosyncronus is a slightly wider range of orbits, but not enough to be safe..

Laser weapons in space are again a fun sci-fi idea, but hardly practical.

1) The object you launch going the wrong way will not have substantial delta-v capability. There are many slots across a wide range of orbits. A hypothetical defensive satellite would only need a few dozen meters/second delta-v to avoid the object. With in-orbit refueling, the orbital satellite has the advantage over a promptly launched weapon.

2) Laser weapons are available for shipborne use today. Airborne defensive lazers targeting Air to Air missiles are currently undergoing tests as part of the 6th generation fighter program. The "sci-fi" you are alluding to is now just a question of power output and weight. If the goal is to disable command and control of a potential impactor satelite over the course of ~30 minutes - the power output requirement needn't be more than a few KW. With a few dozen KW ablative heating of the impactor could push it off course.

The key enabling technology is in cheap, re-usable, heavy-lift. Given this, it will always be possible to put a satellite in orbit with more delta-v capability than any mobile and disposable satellite weapon.

1) The point isn't to launch one object the point is to launch a shotgun blast of 10 million objects each of which can destroy your satellite.

You need km/s delta V to deal with this kind of attack.

2) Lasers are much easier in atmosphere for a huge range of reasons. If something is approaching you at mach 4 you get 1/10th the time to deal with the situation as much 40. Further in space fragments are deadly, a 2.5 gram object at mach 40 has the about kenetic energy as 1 kg object at match 2. Blowing up the rocket aimed for your satellite might not actually help.

Anyway there are vastly better orbital weapons than I just described, the point is any nation that can get mass into orbit can absolutely anailate orbital infrastructure.

* make that 10x not 1/10th

Edited without thinking.

Geosynchronous orbits are way out from the planet and costly, in many ways the "space game" of earth communications, earth monitoring, comms for earth wars has changed.

Constellations of thousands of satellites in near earth obits, precessing for coverage, in near ellipitic orbits for relatively low cost repositioning over tagets of interest, and "not real satellites" - HAPS and blimps are changing the dynamics.

Cheaper to launch, greater in number, and more easily moved about and|or replaced.

> Satellites have few realistic ways to protect themselves

I would imagine it's the same with submarines - the trick is to remain undetected. We already have stealth aircraft, why not stealth satellites? Maybe they are already flying, how would we know?

Subs benefit from hidding in water and being able to move around unpredictably.

Space on the other hand is really empty and satellites have stable orbits.

PS: Stealth aircraft have similar vulnerabilities if they constantly fly the same path. https://nationalinterest.org/blog/reboot/stealth-down-how-se...

In the context of fighting a war, Kessler Syndrome is a meme. It reduces the expected lifespan of a satellite, but that only becomes strategically relevant if the new lifespan of your satellites is shorter than the war is expected to last and satellites are being destroyed faster than they can be replenished. America is rapidly developing the ability to launch a ton of new satellites very quickly.

Of course the post-war aftermath would be deeply regrettable. But it always is.

Depends on severity. Some orbits could become contamintaed enough to destroy satellites in hours if countrys are tossing around anti satellite weapons.

See not to nit pick, but it’s that realm of thinking that is the reason we don’t have that level of technology.

Don’t get me wrong caring for our planet is Noble, but if the other hacker news article (the one that shows the events of our life) there are like 2b more people on the planet then existed when I was born, I think it’s time to tackle leaving the planet otherwise instead of banning fossil fuels we will be banning children.

See: https://en.wikipedia.org/wiki/One-child_policy

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