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maccam94on Starlink Maritime

Power budgeting is basic engineering. They wouldn't install lasers on satellites if they couldn't power them.

maccam94on Starlink Maritime

https://wccftech.com/spacex-starlink-satellite-laser-test/

maccam94on Starlink Maritime

> as far as I'm aware it hasn't been openly demonstrated to work yet

They did a test in late 2020[0], and all launches since June 2021 have been Starlink v1.5 with lasers[1].

0: https://wccftech.com/spacex-starlink-satellite-laser-test/

1: https://en.wikipedia.org/wiki/List_of_Starlink_launches

maccam94on Starlink Maritime

Starlink v1.5 has lasers, and that is what they have been launching since January of last year.

maccam94on What comes after Git

> try to do a squash merge to the main, then do some other changes in your branch, and try to merge again

For this situation, at the end just do:

git rebase -i main

And delete all of the commits that you included in your squashed commit. If you want to preserve your detailed history you can create a new branch for the rebase like so:

git checkout -b mybranch-rebase && git rebase -i main

maccam94on Sshfs Is Orphaned

Beware, you may need to do a significant amount of sysctl tuning/mount option tweaking to get fast NFS performance over high latency networks.

maccam94on The state finally letting teens sleep in

Many suburbs have school buses but no other pubic transportation.

maccam94on Zulip – Threaded real-time chat for distributed teams

Streams are opt-in. Topics are transient and fast to create, and everyone in the stream will automatically see the new topic. You also get per-topic read position tracking, and stream members can mute individual topics if they want. You can also view the entire stream at once (or even all streams!) with the topics interleaved. The sidebar shows the most recent topics in each stream, so inactive topics are eventually hidden from the main UI (though you can still dig them up if you go looking for them).

maccam94on Zulip – Threaded real-time chat for distributed teams

The thread-first model is quite different from the free-for-all channel model in IRC/Slack. Imagine the chaos in your email inbox if messages didn't have subject lines or threads. Zulip makes it actually feasible to follow a chat conversation asynchronously, and it's much easier to manage how many notifications you get.

maccam94on DARPA moving forward with nuclear thermal engine design

Why? Propellant is relatively light in an NTR system as far as I'm aware. I am also assuming that making a nuclear ship aerodynamic would be unfeasible (it will likely be long and only structurally reinforced longitudinally).

maccam94on DARPA moving forward with nuclear thermal engine design

I am assuming that you can spend the delta-v at both launch and intercept, it sounds like you are assuming it is all used at launch?

maccam94on DARPA moving forward with nuclear thermal engine design

From what I've read NERVA was actually killed by Nixon for political (cost) reasons. https://en.wikipedia.org/wiki/NERVA#Cancellation

maccam94on DARPA moving forward with nuclear thermal engine design

>Only at extreme delta V levels do NTRs actually get better performance, but that's not a mission-to-Mars territory

Why is that not mission-to-Mars territory? You can shave months off the transit time with >15km/s delta-v.

maccam94on Starlink for RVs

Starlink orbits are far too low for kessler syndrome. Atmospheric drag would clear them out in <10 years, probably much less. In fact, Starlink satellites are far too numerous for anti-satellite weapons to be effective (at least, until countries decide it's worthwhile to start mass producing orbital-class rockets to attack enemy satellite constellations, which would almost certainly lead to a loss of their own satellites as well). Russia would love to be able to take out Starlink right now, but they can't.

maccam94on Starlink for RVs

Thank you for writing this. I thought I had heard of this guy before. I was about to write a lengthy rebuttal myself.

maccam94on Starlink for RVs

Tesla doesn't have anything to do with Starship launch prices. Let's look at costs to SpaceX for launches, since those are the most relevant numbers:

Reused Falcon 9 launch: $15M[1] in the best case, but let's double it just to ballpark the average, so $30M. Falcon 9 can loft around 50 satellites per launch. 30M/50 = $600k/satellite.

Starship: Aspirational goal of $2M cost to launch. Let's just round that up to $10M for whatever might be more expensive than expected. Starship has been predicted to be able to launch around 400 Starlink satellites at a time, the last figure I saw was that Starship launches would carry "100 plus" Starlinks[2]. $10M/100 = $100k/satellite. This is assuming Starship is launching v2.0 satellites though, rather than the current v1.5, which are way heavier (1 metric ton vs ~290kg)[3].

1: https://www.inverse.com/innovation/spacex-elon-musk-falcon-9...

2: https://spacenews.com/ksc-to-study-potential-new-starship-la...

3: https://www.nextbigfuture.com/2021/09/version-2-starlink-wit...

maccam94on Rust's Problematic Reliance on GitHub

The citizens of Russia could vote out or overthrow their leader. The goal of sanctions isn't indiscriminate pain, it is to incur a cost for bad behavior and encourage people to stop it. I think cutting off technology services to a country fighting a war of aggression against its neighbor is better than most alternative methods of retaliation.

maccam94on Rust's Problematic Reliance on GitHub

The original poster is in Russia, which is why they care about GitHub being involved: GitHub is obeying US sanctions against Russia over the war in Ukraine. Any authentication service operating in the US or in another US-aligned nation would have the same issue. Crates.io itself is also likely bound by these regulations. So at this point realistically the OP needs to mirror crates.io and set up another registry (which cargo will absolutely let you use). This is just another cost to living under a pseudo-dictatorship.

maccam94on Why is the nuclear power industry stagnant?

I think the root cause here is that people are afraid to live near nuclear plants, and would get mad at their political representatives if they got built in their area. Making these limits more stringent makes it look like the politicians are forcing the plants to be safer, when really they are just blocking the plants from being built in their districts at all.

maccam94on No Fixed Address Bank Account

Credit/debit cards and checks are totally different systems. Cards can be checked for available funds instantly. Checks need to be cleared through the ACH system (in the US at least), which is an asynchronous process that might take more than a day to complete. If you cash a check from a different bank at your own, usually it will actually draw funds from your account and the check will be deposited after it clears.

maccam94on I’ve spent my Easter break customizing Neovim

In vim specifically, there are many more powerful and precise movements you can make by chaining motions. But before those can feel natural and fast, you have to keep your hands on home row.

maccam94on Zulip 5.0: Threaded open-source team chat

The main differentiator of Zulip IMO is the threading model. Instead of chat rooms with multiple un-separated concurrent conversations taking place, every message* must start a topic or be placed in one (topics are like the subject line in an email). You can still look at the room and see all of the topics at once, but you can also focus in on a single topic. And it remembers your read progress at a per-topic level, so it's quite feasible to catch up on chats asynchronously. Basically Zulip brings the best things about mailing lists to chat.

*: you can now turn off the topic requirement, in which case messages go into a "no topic" topic. But not using topics kind of defeats the purpose of using Zulip IMO.

maccam94on White House: Developing a Bold Decadal Vision for Commercial Fusion Energy

CFS is aiming to have an operational demo reactor that is net energy positive in 2025, and a full scale reactor feeding power into the electric grid in the early 2030s.

https://cfs.energy/technology

maccam94on YouTube suspends The Hill for playing clip of Trump denying election results

No, it's not weird at all that the mainstream media wouldn't publish such a story without multiple sources right before an election

https://en.wikipedia.org/wiki/Biden%E2%80%93Ukraine_conspira...

maccam94on Announcing Actix Web v4.0

https://www.reddit.com/r/rust/comments/iqq8k9/announcing_act...

https://www.reddit.com/r/rust/comments/t1bim5/announcing_act...

maccam94on SpaceX’s monstrous, dirt-cheap Starship may transform space travel

The ISS orbit naturally decays without regular boosts due to atmospheric drag. I'm hopeful that Starship is fully operational by the time the ISS reaches EOL, maybe a few Starship launches would have enough delta-V to push the ISS up into a graveyard orbit.

maccam94on SpaceX’s monstrous, dirt-cheap Starship may transform space travel

But why not build an even bigger space station by combining payloads from multiple launches?

maccam94on SpaceX’s monstrous, dirt-cheap Starship may transform space travel

Last I heard, reusable F9 launches cost SpaceX ~$30M. The goal is for Starship launches to cost about $2M, for ~5x the payload mass. Starship is also necessary for Starlink launches to be economical for the full constellation deployment.

maccam94on Starship is threatening NASA’s moon contractors

The heat shield isn't a blocker for getting to orbit, it's only needed to recover the second stage. Musk thinks that the Florida launch site will be ready before the end of the year anyway (and sure, add a few months for Elon Time, but they've already built one of them so the timeline should be fairly well understood). The overall economics and reliability may take another year or two to really get dialed in.

maccam94on Starship is threatening NASA’s moon contractors

I think it's likely that SpaceX recognized that FAA approval could take a while, so they started putting more polish into the launch infrastructure, booster, and ship, rather than just trying to iterate on launches as quickly as possible. But that's just a hypothesis from an armchair observer, I'm not sure if they could have rushed launch pad readiness any further. I've also heard rumblings that there may be regulatory issues with the ground storage tanks for fuel/oxidizer that may require changes.