skysight-inc/HackerNews huggingface dataset:
Ask HN: How hard would it be to put a small satellite in orbit?
I'm not talking anything large here.

I fondly remember spending weekends at the local closest-avilable-abandoned-field with my father and shooting model rockets into the sky.

I think we used engines in the B or C range, but I remember there were companies promoting FFF and GGG versions which were simply way too expensive for me as a kid.

This was ~20 years ago so I am assuming the technology has improved since then.

What would it take to send a model rocket with a small radio-controlled satellite into orbit?

I'm thinking like a 0.25Kg package at most. Just an arduino with a solar panel and a radio transmitter.
Google+ Public Hangout Fail
Not to mention the potential damage that could be done to Canvas by Instructure, which is competing with the Black Board behemoth at the (currently) higher ed market.

http://www.crunchbase.com/organization/instructure
$39.10M funding / 2008 startup.
Leo jumps on whatever is new and then as soon as his attention is distracted he moves on to something else. The list of things that he as said he "loved" and then never mentioned again would be endless...
it clearly states:

"Black Image = International Space Station (ISS) is on the night side of the Earth. "
Please consider keeping the default serif font. It lends an air of humble authenticity to the service, giving the impression that it's hosted by some no-BS people who want an alternative to the glossy and boring options for social media.
Can you add so that people can append their emails / attachments to the existing page? Even SMS messages? You can add twitter message to it latter on...
WalMart et al stock bingo cards. Teaching stores have them 10+ SKUs deep. That's one reason I thought BCC would sell - people were empirically happy to pay money for an inferior substitute.
Very cool! Thanks to the whole team for their hard work.
By that definition, I could just as easily argue that requiring different files for every class reduces cohesion. The idea that class definitions and file definitions are in any way related is a leaky abstraction.
Congrats on the 2.0 release!

I highly recommend taking a look at http://middlemanapp.com if you're considering Jekyll. I gave a talk at RailsConf (http://bradgessler.com/talks/middleman-frontend/) about static website generators and found that Middleman handles everything Jekyll does in a much more modular, more "railsy" way by using tilt, sprockets, and all that good stuff.
I'd like it if one of these marketplaces emerged that was more careful about vetting sellers. I've ordered Raspberry Pi-related gear off of two unrelated e-com sites in the past month (one was Tindie) and have yet to receive the goods (or any indication they received my order) 3+ weeks after the funds changed hands.

This isn't kickstarter. When I pay for something, I expect to receive it in a reasonable amount of time, or at least receive an explanation of what's going on. A little transparency would go a long way.
Odessa city: the truth that is to be hidden
Is something explicitly setting it to black, or is total blackness what the camera is capturing?
Silicon Valley heading toward another tech bubble, some investors say
I'm not saying you are wrong, but most of the literature indicates that high cohesion is correlated with loose coupling. The entire industry treats them as an axis so I don't think it is disingenuous for the author to do so.
I'm a big fan of ledger. Very easy to use and very powerful.

One of my first ruby projects was creating a scraper for the Chase mobile website that outputed ledger-compatible text: https://github.com/rkowalick/autobank
I think a better translation of that would be "It takes one to know one."
Hi Eldavido,

Definitely not the norm. Email me directly with your info and I'll dig into it now.

Emile
Founder of Tindie
Emile{at}tindie[dot]com
as if not more interestingly, the same curve is also the solution to the isochrone problem - if the curve were a wire, a frictionless bead sliding down it under gravity would take the same time to reach the bottom, no matter where along the arc it started.
Wow, that's terrible, but I'd prefer if you referred to those people as "out of date OO people" as opposed to "hardcore OO people". Even though I don't consider myself a "hardcore OO" person now, when I did this would bother me.
Why yes, I am. The sack-of-meat Walter Bright was replaced years ago by myself, the latest D-9000 computer. He was always jeopardizing the mission.
The /s indicates sarcasm.

Of course there is Google, Amazon, Red Hat, SUSE, even IBM uses a lot of GPL software...
web development is not a static thing, wakaba is finished but maybe it would be better, using new concepts and technologies, etc... if it still actively developed.
The next Ricky Martin watch him here
love the 2 girls kissing at the end.
My reading of their comment is that there just isn't any light since it's on the night-side of the Earth, and the Sun isn't providing any light over there. If it were over a part of the planet with light pollution, that's probably not strong enough to break through the atmosphere.
lower insurance. no salary.
It makes no sense to say the renewal rate was high enough to remain profitable and self-sustaining, but you can't retain any of your employees. It sounds to me like they didn't have enough renewals to remain profitable and self-sustaining at their current burn rate, and decided to reduce the burn rate significantly in order to remain in existence. Overall, that's bad news, not good.
I think it's ridiculous that this comment got downvoted. I read hacker news every day and want to have a conversation about fulfillment, business models, and maybe learn about various marketplaces and how they're dealing with the problem of fulfillment and inventory management.

Sometimes conversations here can get a little sharp-elbowed, but I can't help but think I'm getting downvoted because I said something marginally negative about Tindie.

Is this what HN is becoming -- say something nice, or don't say anything at all?
At the very least, I guess that would be a good reason to avoid implementing the missile control software as a kernel module.

Or maybe not, since the missile is clearly intended to be destroyed upon reaching the target.
So I'm trying to check this out, but my ruby gems mirror seems to not want to. I get this error:

`ERROR: Could not find a valid gem 'jekyll' (>= 0), here is why:
Unable to download data from https://rubygems.org/ - bad response Gateway Time-out 504 (https://tokyo-m.rubygems.org/quick/Marshal.4.8/jekyll-2.0.1....

Is there any way to specify other mirrors, and is there other mirrors than the Tokyo one that would work better?
Jacques, Shakespeare would call that "damning with faint praise." It does seem to me that Alibaba has an actual underlying business with real business value, but I wonder about the transparency, even with listing in the United States, of a company that does most of its business in China. We shall see what value the market sets on the company at first, and how that works out over time.
here is source that can be annotated http://www.twomargins.com/documents/15 as referenced here https://news.ycombinator.com/item?id=7707505
The math has already been done. Lobbying has a 22,000% ROI. No brainer.

http://www.npr.org/blogs/money/2012/01/06/144737864/forget-s...
I added few comments, what is that? I don't see significant activity there yet.
We have to understand that is a live streaming from 230 miles up in the sky. It might not work 100% of the time, but if you're patience enough, you can enjoy images like the one I just saw:

http://cl.ly/image/2D0G0m0P2R3D
It looks great, and a large list of websites to boot! Wish Github supported more than Jekyll on Pages.
I disagree - I can't stand the look of Threes, or the inconsistency in the first couple of stages of arithmetic.
How Chris Dixon helped me handle Fear
Have you heard of the This Developers Life podcast?

http://thisdeveloperslife.com/
Here are some projects that put new Lisp machine architectures on FPGAs:

LispmFPGA (2008)
http://www.aviduratas.de/lisp/lispmfpga/, https://groups.google.com/forum/?fromgroups=#!topic/comp.lan...

IGOR (2008)
http://opencores.org/project,igor,
https://www.flickr.com/photos/kaitorge/sets/7215760944571932...
Of related interest to HNers: Admin consoles getting owned up is a fairly frequent way that even security-conscious shops lose their web apps / databases / networks, because one often does not code defensively against malicious actions executed by "trusted" users. You can mitigate this quite a bit by putting them on a private network interface and requiring the admins VPN in to use them.
The software doesn't write and maintain itself. So if the revenue can't cover the expense to write/maintain the codebase (i.e., dev salaries), then the app isn't profitable because one of the major costs can't be met out of revenue at 100%.
https://github.com/jimktrains/freebooks is something I started working on a while ago. It stores everything inside git commits and signs each transaction. My goal was/is to make it distributed such that my wife and I can enter transactions separately and then merge them at some later point.
Fundamentally, App.Net is a platform that provides a number of services, including Twitter-like one-to-many messaging, private one-to-one and one-to-many messaging (like Twitter DM on steroids), many-to-many messaging (like IRC chatrooms), file hosting, and some less-obvious features like messages generated by and for machine consumption (that are never seen by humans), etc.

These are the nuts and bolts that can be used to build a Twitter clone (which App.Net did and which is the primary "product" that most of their users used), a Dropplr clone, blogging a la Octopress, personal memory logs (like Ohai[1]), Photo story sharing apps like Sunlit[2], etc.

[1]: http://ohaiapp.net

[2]: http://sunlit.io

Heck, you could even use this to build a Chess app that lets you play remotely with other players, that automatically records every move ever made, and that lets you access your games and history from any device. Basically, anything that involves sending messages (of up to 2k, plus various bits of metadata) between two or more parties and persisting them could leverage App.Net to power itself.

Of course, that's part of the problem. They positioned themselves as a platform, which meant they didn't market themselves very well to end users.
Won't this list be true for every country at some point of time ?

We have to start somewhere.
Well, I'm not surprised that poo.rest is still available.
It's a massive social graph + infrastructure for subscribing to data sources (i.e. other users) and broadcasting messages from one source to all subscribers (including push).

And that's just Twitter. ADN includes a lot more than Twitter does.
I don't know what 10 problems your professor had in mind but his comment was either in jest or perhaps was made from a narrow mathematical viewpoint: variational principles form the basis of much of Physics, e.g. Hamilton's principle, Fermat's principle, etc.

As a side note, for those of you who, like myself, have puzzled how Euler-Lagrange Equations are drived, the answers given to this question are priceless: http://physics.stackexchange.com/questions/885/why-does-calc...
What's the archetype use for Rc anyway? I don't see the point in having a reference-counted object with single thread ownership.

Also you only pay to synchronise shared_ptr when you take a copy of the pointer... I can't think of anywhere in a sane, well-structured algorithm where this would bite.
To get you started, Tsiolkovsky rocket equation:

http://en.m.wikipedia.org/wiki/Rocket_equation
There's 3 Backers going on right now. A poster, a shirt, and an iOS app. They're listed on the page you linked to.
I'm not sure if this offer is still active but this will give you an idea of the difficulty:
http://armadilloaerospace.com/n.x/Armadillo/Home/News?news_i...
Google Drive Outage Sends Students Into Panic
> I was hoping someone would integrate the two into a single client

My belief is that Twitter's rules prohibited doing precisely that. There are multiple developers that expressed an interest in creating a single app for viewing both, but never did so because Twitter would have revoked their API token.
Quite disappointed the developers have decided to stick with Liquid templates. With such a handicapped and useless template language, jekyll is a non-starter for any website more complex than something you could trivially write yourself.
To me, this is extremely relevant for investors in a startup who need to determine if established demand is generalizable.
I would love to use this as a desktop background :)
$3/mo is considered rich?
Thanks for this. Also crazy. Everywhere I look, more crazy.
That is standard practice in many languages.
Boost has 'string_ref'[0] for this. Something similar is currently a standard proposal under the name 'string_view'[1]

[0] http://www.boost.org/doc/libs/1_55_0/libs/utility/doc/html/s...

[1] https://isocpp.org/files/papers/N3921.html
500k users for a startup, begs believe for me.
Techcrunch has a startup listed as having 500k users . This begs believe for me.

http://techcrunch.com/2014/05/06/smore-raises-1-7m-seed-round-for-its-single-page-website-builder/

If the figures are real, how on earth does a startup get those sorts of figures in a market that seems expensive to market to
I know, I was thinking there needs to be a local network RNG, maybe it is run by switch and accessible over UDP or raw ethernet frames.
no, but it makes sense!
Back in 2007, I built a "social search" Web app called CoReap, based on a similar concept. Unfortunately, I couldn't run it for long (and eventually pulled the plug) due to infrastructure issues. You can read about at http://coreap.wordpress.com

Best wishes to you guys! Drop me a message if you have any questions or need any help.
Won't happen. Hacker News is the Minimum Viable Product.
It works for me - where are you running it? I've heard it breaks on OS X, but don't have access to the platform to experiment.
FYI, you can access a buffer's menus, while menubars are disabled, with C-<mouse-3> on the buffer.
i'm assuming the solutions involved proving that there was a unique curve that satisfied the constraint. seems pretty non-trivial though.
So to reify a type involves making an abstraction, which is odd because reify seems the inverse of making an abstraction...
The Streamlined Life
China’s Property Bubble Has Already Popped, Report Says
The stats (as they are quoted here) are just exactly what you would expect to see if you looked at early adopters.

New products typically fail. If you are a consistent early adopter, you will buy a lot more failures than someone who sticks to tried-and-tested products.

If anything, "twice as many" is lower than I would have thought. In my opinion, this suggests that early adopters are rare - that there isn't a novelty-seeker type of person who goes around trying new products for the sake of it.

What they should be measuring is slightly different than this. If these people buy a new product, does that make the product more likely to fail than it would otherwise? (Given that the product is likely to fail anyway)

As I've understood, this stricter statistic is not seen in the article. Even if we could identify people like that, I would put those people into the category of "temporarily unlucky early adopters" and would not expect them to have predictive power.

With that in mind, the conclusion of the article seems nonsensical.
Hello, Gophers Rob Pike's opening keynote of GopherCon 2014
Concussion gave a man special math abilities
> When 23 million people are talking about your little weekend project, you have changed the world.

How has 2048 changed the world?
Well the way I see it (speculatively from the outside), the "moonshot" (throws up in mouth) is just the thing you write at the top of the whiteboard. But what you're really up to is solving the 50 relatively smaller, domain specific problems that need to be solved in order for the "moon--hghhh" to be achievable.

This green architecture software is likely a solution to one of those smaller problems. The team was probably so happy with their work they decided they wanted to pursue it as a standalone company. Google let them spin it out and invested seed money as well.
All the companies that make up Alibaba
pg is gone, who will fix it now
That's funny, I started playing Threes, was addicted to it for a while, and when I found 2048 I never looked back. I find 2048 to be a clearly superior game both in terms of visual clarity and repeat playing. The mechanics of Threes are super annoying, especially the end game swipe when there are no more moves, swipe through the pointless point tallying, click next, etc. etc. etc. The cutesy noises and animations seem sort of unfinished to me.

The max card I've gotten with threes is 384, while the max card I've gotten on 2048 is 8,192. With Threes I don't really care about not getting any better, while with 2048 I feel close to getting 16,384 and still think it's interesting to do so. Threes just doesn't have the staying power, the mechanics are simply more frustrating.

I've seen your argument before -- the big post the Threes guys did had it also, that they felt their game was clearly better. I can understand why they felt that way, but I don't get it. And given the taking over the world popularity of 2048, I'm not sure that the evidence is there to support that position.
until it's not [viable|minimum]. we'll see which.
V8 Optimization killers and their workarounds
Everything has really been working great overall on the site. I don't normally chime in on these HN political pages, but this issue is quite bothersome.
Sure, there are going to be a few performance sensitive workloads that you can't use it on, but for the vast majority of issues I've used it for, it's been far more useful than perf or dtruss (on Mac OS X, I've never used dtruss on Solaris so I don't know if it's in better shape).

The big advantage is that it already knows how to decode most syscalls, decompose flags into symbolic arguments, decode things like stat return values, and so on. dtruss on Mac OS X can decode some syscalls, but doesn't generally know how to decode structures or pull apart flags, so there's some information you just can't see, and some which you have to laboriously manually decode. perf, as you note, decodes even less than dtruss. When I'm trying to debug an issue, the more information I can gather and see at once, the better.

Very few of the occasions I've had to use these tools have been particularly performance sensitive. Your example of the huge difference is because dd is copying fairly small blocks at a time, and thus making a fairly high number of system calls relative to the amount of data being transferred. Usually, I'm just looking for why an operation fails, or why a process is stuck; if it takes a little longer to get to that failure, that's OK, and if the process is stuck then stracing it generally won't affect performance.

sysdig looks pretty interesting, thanks for the reference! It's too bad they can't use the existing perf infrastructure in the kernel, and need to add their own kernel module; that makes it that much more cumbersome to deploy and use.
Great read, definitely gave me some ideas for securing my systems.
Although "the lion's paw" thing has been much quoted note that the details of Newton's solution were not preserved, there's only a single paragraph that was published by Leibniz that gives a geometric solution. Assuming Newton did indeed followed a geometric argument to arrive at the solution, Bernoulli's approach that morphs the problem into the equivalent one of light traveling through a medium of varying index of refraction is much more original and more brilliant.

To see Bernoulli's solution and for some additional interesting information about the problem see http://fredrickey.info/hm/CalcNotes/brachistochrone.pdf.
Unless you misunderstood your professor, what they said is entirely and utterly wrong. Calculus of variations is one of the guiding principles of modern physics. Pull out any textbook on quantum field theory or general relativity and there will be a section dedicated to using calculus of variations to derive the equations of motion. Heck, for a lot of theories, writing down the action and deriving the equations of motion from the Euler-Lagrange equations is the first thing you do.

Plus calculus of variations is closely related to differential geometry, which is a massive field. Same with control theory, another massive field with close ties to differential geometry and calculus of variations.

I have no idea what point your professor was trying to make.
Unless I'm missing something here, lacking parametrization is not the issue here. The issue is that it's obvious they are saving the password in plaintext instead of hashing it, otherwise the password would never get close to an SQL query to allow injection.
Sounds to me like they just analyzed a bunch of data and found that there were some people, in that historical data set, who consistently bought products that fail.

For this to be science, instead of just finding random correlations, they'd have to take those people and see if they _continue_ to buy products that fail.

Otherwise, sure, I have no doubt in any big enough data set, there will be some people that happen to have done whatever you want to find. Doesn't mean there's any predictive power in it.
I can't speak for others, but for me, this is how 20148 changed my world

I realized, when I played 2048, that I could have built it too. This was enlightening because I realized we were confined by the limitations we place on ourselves. It changed my view of the world, at least, and hopefully of some more developers like me.
Anything that hurts Blackboard can't be ALL bad.
Technically i understand its importance but in terms of UX this thing is terrible. For a non English speakers, they usually take some time to reply and most of the time they end up with `expired link`. I doubt the user who wrote very big comment (usually highest rated comment in that thread) use HN editor, I guess they first write in the word processor and then copy it here since the amount of time it involved in writing comment is not sufficient.
Here is dang's official response on the matter from 10 days ago:

[0] https://news.ycombinator.com/item?id=7651770
Right. That confirms my point.
That made me smile. But HN isn't a product- its a marketing tool.
Make sure to get a full refund on all the money you've paid to Hacker News. They clearly owe you and are failing terribly. The bastards!
The Day I Started Lying to Ruth
Absolutely. I use microca.st every day. The platform only keeps getting better.
That's what they're doing with Google Shopping Express. Eventually self-driving cars will be doing the deliveries.
Releasing the source code would be an obvious answer.
Mobility Capability Package 2.1 (NSA)
Probably... but more and more people are starting to use snapchat as their camera app (for the build in captioning)
#opensourcehn
If you see a blank screen it's night. You can see the current location and day/night status here: http://iss.astroviewer.net/
I really like Jekyll and use it for both my website and blog. It really is a great product that is easy to use. Thanks!
What is the recommended way to handle database migrations with deis? In this case I don't want to automatically deploy on push.
I'm sure that adding a small disk with the source code to the warhead would be an acceptable and valued solution.
I found that as well, but it is not what inetsee described in his post.

I was interested specifically in "using Racket's macro system to implement a slight variation of Algol 60", which is not what that section or the Racket guide section on macros [0] does.

It's not clear what was meant by "the Racket tutorial".

[0] http://docs.racket-lang.org/guide/macros.html