djexjms (u/djexjms) - Readit News

djexjms commented on Open-source communications by bouncing signals off the Moon open.space/... · Posted by u/fortran77

shakna · 3 months ago

It's not even a byte per second. The latency of the distances involved mean you're looking at around two seconds per round trip, plus a little extra because of the fuzziness of radio in space and absolutely everything that can distort it.

There's a lot of math that goes into selecting the right bit-width for the signal, which I ain't doing here and now [0], but most 24dB things tend to be 32bit for reasons. The arrays here are a bit more, but probably fit that kind of channel.

Assuming 32bit and 30dBi, you'd be sending at roughly 20-30MHz, and receiving at about 1kHz. (Less if you hit bad weather.)

So... 1 bit per second. Not byte. Bit.

[0] https://www.spaceacademy.net.au/spacelink/spcomcalc.htm

djexjms · 3 months ago

This is obviously incorrect. Latency is not the same as bandwidth. EME hobbyists will bounce voice signals off the moon.

djexjms commented on OpenMW 0.50.0 Released – open-source Morrowind reimplementation openmw.org/2025/openmw-0-... · Posted by u/agluszak

ascagnel_ · 3 months ago

My thought has been a 20- or 30-year term, with one or two renewals at a nominal fee, would work wonders. Orphaned works basically disappear overnight, and the vast majority of works will have exhausted their useful commercial life within those 20-30 years.

I'd also argue that works eligible for copyright must submit a modifiable edition (eg: source code or a DRM-free copy) that is made available to archivists immediately and the general public once the copyright term expires.

djexjms · 3 months ago

20 to 30 years would ensure that abandoned media that was formative to a person growing up will enter the public domain within their lifetimes which would be a nice thing to have in my opinion. It would also ensure that any work done by an artist during the early phase of their career (the phase where artists are most likely to agree to lopsided contract terms) would stand a chance of reverting back to the public domain before the end of that artist's career. Very very few works are making any significant revenue after 30 years. I think a system where initial copyright is free for 20 years, with the option of renewing for an additional 10 years for some fee, and then the option to renew annually after that would be fair. For the very small number of works that are still commercially viable after 30 years, the publishers can figure out how long it makes sense to keep renewing the copyright. Otherwise it really is in the public's best interest to have a robust public domain. Many fewer works would go missing that way.

The way the copyright is structured right now is the result of regulatory capture. The cost of these long terms of copyright is the loss of books, movies, music, games, etc. Millions upon millions of hours of creative labor have been lost. These costs are born by everybody that will never have to chance to have access to that media. The benefits of these long copyright terms are only the publishers. Having an annual renewal fee for copyrighted works published 30 or more years ago would be something that would be a visible cost in the books of large publishers. As it is it is too easy for them to ignore the downsides of long terms of copyright. I am not claiming that no media would be lost if we had no copyright, but the efforts of archivists are difficult enough as it is. Media that is no longer being copied is destroyed eventually. Obviously making it a felony to copy something will reduce the number of people making copies of it. That's the whole point after all.

djexjms commented on NASA chief suggests SpaceX may be booted from moon mission cnn.com/2025/10/20/scienc... · Posted by u/voxleone

allenrb · 4 months ago

There is just so much wrong with this from start to finish. Here are a few things, by no means inclusive:

1. We’ve already beaten China to the moon by 56 years, 3 months, and some change. And counting.

2. Nothing based around SLS is remotely serious. The cost and timeline of doing anything with it are unreasonable. It is an absolute dead-end. The SpaceX Super Heavy has been more capable arguably as early as the second flight test and certainly now. They could have built a “dumb” second stage at any time, but aren’t that short-sighted.

3. Blue Origin? I’ve had high hopes for the guys for two decades now. Don’t hold your breath.

4. Anyone else? Really, really don’t hold your breath.

This whole “race to the moon, part II” is almost criminally stupid. Land on the moon when we can accomplish something there, not just to prove we haven’t lost our mojo since Apollo.

djexjms · 4 months ago

Sure the SLS is a total mess, but from what I understand, there wasn't ever really a concrete plan on how to use SpaceX rockets to actually get to the moon. The following video is a presentation given at a NASA meeting explaining the issue.

https://www.youtube.com/watch?v=OoJsPvmFixU

djexjms commented on The surprising geography of American left-handedness (2015) washingtonpost.com/news/w... · Posted by u/roktonos

cperciva · 7 months ago

To the people downvoting labster's comment: He's making a joke about left-handedness being referred to as "sinister" due to the Latin origins (apparently this may originate from how Romans wore their togas). He's not saying that teachers are making children any less evil.

djexjms · 7 months ago

Wait a minute, that doesn't sound right.

djexjms commented on Show HN: OffChess – Offline chess puzzles app offchess.com... · Posted by u/avadhesh18

chatmasta · 7 months ago

Awesome. I’ve never understood why Lichess limits the offline download to 50 puzzles.

djexjms · 7 months ago

For what it's worth, the entire Lichess corpus of puzzles (over five million positions with solutions and theming tags) is available for download in CSV format at https://database.lichess.org/#puzzles

djexjms commented on ICEBlock, an app for anonymously reporting ICE sightings, goes viral techcrunch.com/2025/07/01... · Posted by u/exiguus

93po · 7 months ago

Cops should be proud to put their lives at risk. It should be part of the job expectations. You should care so much about the community you're supposed to serve that you'd be willing to make that sacrifice, even for a total stranger. The fact that none of this pride or expectation exists highlights that cops are cowards who get into policing for bad or selfish reasons and perpetuate systemic problems that harm millions.

djexjms · 7 months ago

That's a nice ideal. I honestly kind of agree with you in the sense that I wish that was how things were. But in my view, it's easier to think about the police as a force whose primary purpose is to enforce the property rights of the capital holding class. In the United States there have been court rulings clarifying that police officers are never obligated to risk their lives.

If you look at the actual numbers, at least in the US, policing can really only be viewed as a risky profession from a white-collar point of view. According to OSHA, construction workers, truck drivers, farmers, and even pilots all have a greater likelihood of dying on the job.

djexjms commented on ICEBlock, an app for anonymously reporting ICE sightings, goes viral techcrunch.com/2025/07/01... · Posted by u/exiguus

djexjms · 7 months ago

What about ignoring due process while doing so? Is that, in your view, in line with the constitution? If it is, what recourse does a US citizen detained by ICE (either accidentally or not) have? Also, how do you view Trump's efforts to end birthright citizenship via Executive Order? Birthright citizenship is in the 14th Amendment. If the president is allowed to arbitrarily redefine who is and is not a citizen, are constitutional protections anything more than ink on paper?

djexjms commented on I will do anything to end homelessness except build more homes (2018) mcsweeneys.net/articles/i... · Posted by u/2color

djexjms · 8 months ago

Reading this comment thread was a fun way to start my day. Always funny to see people react to satire about them.

djexjms commented on Google I/O '24 Puzzles io.google/2024/puzzle... · Posted by u/PennRobotics

djexjms · 2 years ago

Things started getting tricky at level 7. I can see that level 8 is solvable, but I'm not going to have time to solve it before leaving for work. Neat little puzzle.

djexjms commented on New cognitive science tool to shed light on mental health darpa.mil/news-events/202... · Posted by u/rglover

derbOac · 3 years ago

My impression (I do research in this area broadly speaking) is that this sort of tool is not really very strongly related to the reasons why they present no warning signs, etc.

Implicit measures tend, on replication and rigorous scrutiny, to kind of be very broad brush and not very specific. There is a literature on implicit measurement and suicide, and it seems they hold up, but they don't dramatically add to anything, and there's also tricky issues about the meaning of "preconscious" assessment. So, lots of false positives etc, and also maybe even bigger questions about the meaning of implicit processing relative to conscious opportunities for "revision".

I think the problem is, what good does it do if someone has some predilection toward suicide but isn't aware of it? If they were going to be resistant to addressing it without this tool, why would they be less resistant to it with it?

The problem with suicide prediction has never really been in predicting suicidal attitudes or cognitions, it's been predicting the actual follow-through with an attempt or success. That depends on a lot of stuff that exists outside of attitudinal space, for lack of a better way of putting it. Someone can basically feel disturbed by the idea until they don't, and then change rapidly in their feelings about it, or vice-versa.

I can't say I think this research line is a bad idea; I think the more information the better. But I'm really skeptical about how well it will work up when really skeptically evaluated, with lots of data, especially when you put it to practice. There's a lot more hurdles than people think.

djexjms · 3 years ago

Even if it turns out not to be the perfect solution, it might turn out that this kind of measurement might be useful for things like estimating the effectiveness of medication and other medical interventions, or even lifestyle changes. Imagine if this kind of thing could be turned into a medical device. Many people who end up committing suicide have had previous suicidal episodes. Being able to have a technology that people with known suicidal tendencies can use to help keep tabs on their own mental health could potentially be as useful to them as blood sugar monitoring is to diabetics.