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chris_va

oo, fermi estimate time!

Typical 50% RH at ground level is ~7g/kg air, air is roughly 1kg/m^3, so between the surface and the planetary boundary layer (let's say 1km) is about 7L of water per m^2 of surface. Moving along at ~3m/s means 21L/s passes by each meter of fence line.

PBL probably mixes after about 50km, so it takes ~5 hours to normalize after you pull out water at ~5 knot wind speed. If you want to not make a dent, means you can pull less than 1L per m^2 per hour, or about 8m^3 pear, which is about 8x the yearly requirement for farmland.

So, you can irrigate a farm and your neighbors would mostly be fine.

(math not checked)

Very much not a new idea: https://en.wikipedia.org/wiki/Very_low_Earth_orbit

Though fun to see. More interesting than the station keeping (indefinite part) is that it enables ~100km orbits, which are ~5x closer than what remote sensing satellites use today and thus could get 5x the resolution for the same instrument.

Re:California is chasing wealth that has feet on Friday September 25, 2026 @12:08AM (#49840109)
Landlords are competing with each other, and renters can take their next best alternative. If everything gets strictly more expensive, the next best alternative is not necessarily any cheaper...
Re:Italian parliament votes for return to nuclear energy on Wednesday September 23, 2026 @08:50PM (#49824758)
I do a lot of work in this space, including all that modeling you mentioned. "Solved" is a bit of an overstatement. The system works, and it can work with renewables+storage (modulo total supply of BESS is not there yet). However, there is high tail risk to not having steady baseload power.

And, even under ideal conditions, baseload is still quite hard. Especially in Southern Europe (e.g. which has quite a bit less land than Australia, and less wind than the nordic countries).

Fundamentally, I agree that it boils down to cost, and the people writing $XXB checks are generally pretty good at financial modeling. If nuclear makes sense, and the regulations allow it, they will build it. However, it's fighting against a highly variable, zero-marginal-cost renewable market with something that is high capex. Same reason people don't build new coal in the US despite certain politicians trying to popularize it.

My guess... If it does take off, either it will have to be wildly cheap (unlikely), or there are geopolitical concerns about the gas backup that Italy currently relies on so heavily to make the renewables work.

never underestimate the bandwidth of a station wagon full of tapes reentering the atmosphere
Re:Can gzip be a language model? on Tuesday September 22, 2026 @10:06AM (#49801524)
We used a similar technique for a class project (N decades ago) to test this:

https://en.wikipedia.org/wiki/Baconian_theory_of_Shakespeare...

By looking at mutual information from different authors on the same topic vs same author on different topics. As I recall, it convincingly disproved the hypothesis.

Re:Tell HN: OpenAI keeps re-enabling the 'allow training' setting on Thursday September 10, 2026 @11:19AM (#49645266)
Don't forget the not-actually-Open-no-longer-a-non-profit history
Re:You Know Who Hates AI? Insurance Claims Adjusters on Wednesday September 02, 2026 @09:57AM (#49536343)
well let's hope we don't cover him
I am kind of amazed how negative the comments are here, especially on HN.

Learning to hack something together in high school using the latest technology (vacuum tubes, radios, microprocessors, web/javascript) has been a common theme in the tech world for generations. With LLMs and online tutorials, this isn't even a difficult suggestion. Do people think learning new tech is somehow wasted effort?

I know extensive thought goes into filters in front of the camera and the lighting, but one can probably change the bayer filter transmission function to get them to match better (and maybe add one or two channels at the cost of shot noise).

I see this in industrial cameras, do you know if any filmmakers use non standard Bayer filters?

GAO's task is a bit broader, no?
Yeah. I don't think the conclusion is necessarily wrong or that they shouldn't have investigated, but I also think the cost to the taxpayers might increase due to the underlying nuance. The report implies that the guidelines are correct, but doesn't really quantify the counterfactual.

Again, devil's advocate

To play devil's advocate, the counter argument is that it's always easy to advocate for more process, and cherry pick examples to support that conclusion.

The actual report basically says that the DOE already requires that they "should identify a need without having a particular solution already in mind", so it is really just an argument that people should follow the written guidelines, and add more process to make sure it happens. The examples in the report are pretty nuanced.

Only if there is a local glass processing facility + consumer (e.g. large brewery, etc) is it worthwhile.
It's really the alkalinity (e.g. the Mg++ or Ca++), which silicate rocks often have (but technically not limited to silicates).

As an aside, we need to dissolve roughly one large mountain into the mix layer (top ~50m) of the ocean to have it fully take up atmospheric CO2. Without dissolving, the reaction is very slow (co2 in atmosphere => slightly lower pH rain => reaction with mostly passivated rock + erosion).

I wouldn't say liquid is "better". The neutrinos don't care from a cross section standpoint.

Uniformity of the light field is going to be different, but that is not my sub-domain.

The size of the detector can be very large, stable, and protected with an ice cap. https://icecube.wisc.edu/science/icecube/

There aren't a lot of places with multiple km of water without things like animal life or other confounders.

Re:Can You Find the Comet? on Tuesday April 28, 2026 @09:58AM (#47934698)
Not to disagree, but stacking a series of exposures with a sigma-clipped mean (or similar) should still get a nice image.
I am not arguing either way, but I think you missed the point.

When you give O(20000) people you have a 1-0.9999^20000 (high) probability that that will leak anyway (either 1/20000 people not following the rules, or just the accident/attack surface area).

The poor grid.

The US added basically 0% extra transmission capacity last year.

... Now your local charging station will require a nuclear plant to keep up with ~1MW per car.

Re:Fusion Power Plant Simulator on Tuesday April 21, 2026 @02:04PM (#47852221)
For pulsed power, with an optimistic beta of 1, the magnetic field energy is going to be comparable to the heat energy. The house load here seems tied to a static superconducting coil, not a pulsed field.

And can in many cases be much higher than the heat energy (e.g. theta pinch).

Re:Fusion Power Plant Simulator on Tuesday April 21, 2026 @01:41PM (#47851958)
The recirculating power for the magnetics should be included (at least for pulsed), as the RTE there tends to drive the design.
Re:Sauna effect on heart rate on Monday April 20, 2026 @11:24AM (#47835684)
This would not pass peer review for a journal as written.

Maybe the conclusion is correct, or maybe not, but as written the methodology is under specified, statistics are not supported, and there too many confounders not addressed. One should not take anything from this without a better write up. Just misunderstanding what n= means is a huge flag.

Since the author is here, I have to ask: Why a blog post and not an actual paper? Why spray this onto the internet without validating the work? Or, conversely, why not caveat the work as exploratory data science?

Re:God Sleeps in the Minerals on Wednesday April 15, 2026 @01:38PM (#47782472)
I am sure there is a great list somewhere of places to see stuff like this (or I can ask an LLM), but I can vouch for

Mines Museum of Earth Science (Golden CO) and The Harvard Museum of Natural History (Mineralogy room, Cambridge MA)

Re:Artemis II safely splashes down on Friday April 10, 2026 @10:12PM (#47726566)
Agreed.

Fun info: The NASA orbital codes include things like photon pressure... from sunlight reflected off of other planets in the solar system. At some point, I think they are just showing off :)

Re:1D Chess on Friday April 10, 2026 @04:23PM (#47723216)
In chess they cannot move onto a spot that would put them in check. If they can make no legal moves, it's a stalemate.
The actual language (I think): https://legislature.maine.gov/legis/bills/getPDF.asp?paper=H...

It explains the intent (to protect consumers/grid from price changes and fluctuation), and bans 20MW+ loads. They forgot to define load, so a behind-the-meter datacenter (zero net load on the grid) still would likely not get permitted even though it does not violate the intent of the law, which is a bit odd.

I think people today are more focused on how OpenAI released a model "too dangerous to release", not that they were right or wrong, as part of the general trend of criticizing OpenAI for not following any of its stated principles.
Re:Lazycut: A simple terminal video trimmer using FFmpeg on Monday March 16, 2026 @02:47PM (#47403068)
Invoking ffmpeg, gzip and tar commands is a sort of reverse Turing test for LLMs
Surprisingly, the natively english speaking world is about evenly split on "soccer" vs "football".

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