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frayestoon Astrodynamics Textbooks on My Shelf

BMW is a classic from my time at USAFA. It's a great book and ideal for those beginning in Astrodynamics.

I bought it from an upperclassman for 25 cents.

Still on my shelf and I used it to design my own astrodynamics course to teach during grad school.

frayestoon Amazon’s Project Kuiper books 83 rockets to launch internet-beaming satellites

well, the kessler syndrome [1] is a real phenomenon and has real consequences. More satellites == more debris == high probability of collisions which can create a positive feedback loop.

It requires real management and processes ahead of time, not after the fact.

[1]: https://en.wikipedia.org/wiki/Kessler_syndrome

frayestoon BBC resurrects shortwave broadcasts as Russia blocks news of Ukraine invasion

I'm interested and considering getting an amateur radio license.

It's not clear yet, but I wanted to get a single portable device that allows for reception of all the most important frequencies, which I think includes shortwave, HF, VHF, NOAA weather and the amateur radio bands.

Is there a device that does all of this?

frayestoon Nature Neuroscience offers open access publishing for $11k per article

Not sure what other people do, but I always publish at a journal then put my manuscript on arxiv, or whatever field equivalent, and then on my personal website.

Then I submit it to scihub.

Best we can do these days

frayestoon Show HN: Processing 24 hours of video in ten minutes

This is relatively simple to create yourself.

There are closed form equations that can be used for the angular position of the sun, which will be more than accurate for this purpose.

Then it's mostly some simple trig to determine areas that have a line of sight to the sun.

I have this on my to-do list because in my bedroom on a full moon the light will come through one specific window onto our pillows. i wanted to automate either curtains or something to predict when it'll happen.

Maybe eventually I'll get around to something like this

frayestoon ‘Hard’ skills from PhDs remain relevant beyond academia

I will say that at multiple job interviews people have commented and been impressed with my LaTeX CV.

So it's a plus!

frayestoon Ten Years of Logging My Life

I want to track sex. So far it's been a spreadsheet.

Is there anyone else with a better method?

frayestoon Three hours to save Integral spacecraft

I think what they are referring to is "angular momentum dumps". The reaction wheels have a fixed maximum amount of angular momentum. This is a function of the speed of the wheels themselves since the mass/moment of inertia is fixed.

Over time external forces continue to add momentum to the system (from drag/solar radiation pressure). In order to maintain a desired pointing direction this means the wheels must increase in velocity to "absorb" this momentum.

Eventually you need to "dump" the momentum using another external force, such as thrusters, or in this case the same solar radiation pressure.

Goal is to orient spacecraft such that external forces can be used to spin down the various reaction wheels, thereby "dumping" momentum out of the wheels.

This is pretty common on all spacecraft, but gets complicated/innovative when you have to do it in an emergency or if you don't have a full set of reaction wheels.

frayestoon Apple Joins Blender Development Fund

I think Blender does have a Python API [1]. I used this somewhat during my graduate school days to do rendering.

[1]: https://docs.blender.org/api/current/index.html

frayestoon Neovim 0.5 is overpowering

vim-fugitive is my goto

frayestoon Ford unveils the F-150 Lightning, its all-electric pickup truck

I think that 1800lbs is actually the weight capacity of the truck if I'm reading the article correctly.

I'm trying to find the mass of the battery to compare the energy density to the Tesla battery packs

frayestoon Reverse engineering the Nest home/away API

Can also use a router integration. I have a mikrotik and it tracks DHCP clients which I use for presence detection using a bayesian sensor

frayestoon Last Airworthy MiG-17 Is Up for Sale

I'm not an expert and have forgotten most of my aerodynamics classes but I believe it's related to shockwave formation on the wing tips or possibly pitot tubes to measure airspeed as a function of pressure changes

frayestoon How Allstate’s auto insurance algorithm squeezes big spenders

Another USAA member here. I haven't had to do an auto claim yet, besides simple windshields, but have had several property claims.

They have been great. In fact, right now USAA is in the subrogation process against the offending party for a claim on a bicycle.

I've been happy with their insurance products, their even better customer service, and have no plans of changing.

frayestoon EU Commission to staff: Switch to Signal messaging app

Still protected by the math?

All the three-letter agencies already knew they had these tools available, GPG, veracrypt, Signal, etc.

Now it's just impossible for governments to whole sale eavesdrop on conversations. If they want access it now has to be targetted, and most likely device specific which is harder.

frayestoon 82nd Airborne unit told to use Signal or Wickr on government cell phones

https://signal.org/bigbrother/

You can see exactly what Signal is able to provide to a legal request. Time of last connection related to a phone number

frayestoon LastPass stores passwords so securely, not even its users can access them

Yes, the lastpass exporter has an issue. You can do a search and replace.

Or you can do what I did and when I reach a site that had an issue, I would just look at the password and there would be an obvious parsing error, e.g "&" is instead "amp&" and would just modify it manually.

Only happened a few times and then all is good.

https://github.com/bitwarden/help/blob/master/_articles/impo...

frayestoon How to Read a Paper (2016) [pdf]

You can also go here for almost all papers

https://whereisscihub.now.sh/go

frayestoon Have Aliens Found Us? (2019)

So we can determine the orbit using only line of sight measurements of the object relative to the Earth.

This is a problem originally solved by Gauss for Ceres.

https://en.wikipedia.org/wiki/Gauss%27s_method

More generally given sufficient observations one can use many similar methods of orbit determination to get a relatively accurate orbit of the body. All of this is standard stuff in astrodynamics and happens on a near constant basis for both man made and natural objects.

A good introduction is the classic BMW

https://www.amazon.com/Fundamentals-Astrodynamics-Dover-Aero...

None of this requires the shape or material of the object, just some fuzzy measurements of the position

frayestoon "Google Stadia is not a product that exists because people want it"

What syncing ability are you referring to?

frayestoon "Google Stadia is not a product that exists because people want it"

Google photos?

frayestoon Luxembourg to be first European country to legalise cannabis

What sucks in the US is that cannabis is still federally illegal. So you if work in a government job/military, or smoke on federal property you can be charged with a crime

frayestoon Matrix 1.0 and the Matrix.org Foundation

I'm also really interested in setting up a bot/bridge with our Matrix server.

Anyone know of a bot that will send emails for messages in a room? I basically want to bridge a room with an already existing email list to send out announcements using Matrix.

frayestoon An Orbit Map of the Solar System

The reason it's showing those interesting paths is because it's plotting the relative motion of the planets with respect to the Earth.

So visualize the moving Earth in the center of each image with the other respective planet moving relative to the Earth. Since both are moving and rotating about the Sun we get these interesting motions with a lot of structure.

This is the theory of epicycles which was the main theory of the motion of the planets before the heliocentric view became prominent.

frayestoon A visualization of the prime factors of the first million integers

There's a lot of interesting structure. Does this suggest some kind of structure to the space of prime factors or is it just trying to attach meaning where none exists?

frayestoon Firefox 57.0 Released

Anyone else use PocketCasts web player? Chrome is able to play audio at 2.7x speed without distortion while Firefox still has issues.

Is there a location where I can submit a bug report?

frayestoon In rich and poor countries, researchers turn to Sci-Hub

As a graduate student, I've been quite determined to post all of my papers and code to github/arxiv/personal website.

Most journals allow you to freely distribute pre-prints, and most researchers I know do this very frequently.

The entire scientific publication environment is quite convoluted but there is a large effort for open publications.

frayestoon In rich and poor countries, researchers turn to Sci-Hub

I'm a young graduate student and face this on a continual basis.

Articles are difficult to find because our university does not pay the subscription charges.

I need to publish my work in quality journals, all of which charge high publication charges. Some are even higher if you want a 'public access' option.

Luckily, there is a growing movement for open research and open publication. Many researchers, myself included, will publish pre-prints and papers to arxiv or self-host them on personal websites.

I'm extremely grateful for sci-hub and just hope I can help end this stifling of scientific research in my own way. All of my work ends up on github/arxiv for anyone to use.

frayestoon Signal Desktop

I have Signal on Chrome on multiple computers. It works just as expected with messages shared across Chrome and to the phone.

It's all very fast and working quite well.

frayestoon Signal Desktop

They're using Google groups to manage the beta testing program.

Make sense since that's how you sign into the Chrome app store to download the app.