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Retweet of xeni

Feb 25, 10:15
Yep. #nightlyshow

Retweet of amirrajan

Feb 11, 6:46
Somebody please make this text based game a reality. …

Retweet of mayabielinski

Feb 9, 9:20
Gender bias on GitHub: women's contributions accepted more often than men's - except when gender is identifiable. 

Let's Encrypt Setup

Feb 4, 2:48

I use for my webhosting for my personal website and I've just finished setting up TLS via Let's Encrypt. The process was slightly more complicated than what you'd like from Let's Encrypt. So for those interested in doing the same on, I've taken the following notes.

The standard Let's Encrypt client requires su/sudo access which is not available on's servers. Additionally NFSN's webserver doesn't have any Let's Encrypt plugins installed. So I used the Let's Encrypt Without Sudo client. I followed the instructions listed on the tool's page with the addition of providing the "--file-based" parameter to

One thing the script doesn't produce is the chain file. But this topic "Let's Encrypt - Quick HOWTO for NSFN" covers how to obtain that:

curl -o domain.chn

Now that you have all the required files, on your NFSN server make the directory /home/protected/ssl and copy your files into it. This is described in the NFSN topic provide certificates to NFSN. After copying the files and setting their permissions as described in the previous link you submit an assistance request. For me it was only 15 minutes later that everything was setup.

After enabling HTTPS I wanted to have all HTTP requests redirect to HTTPS. The normal Apache documentation on how to do this doesn't work on NFSN servers. Instead the NFSN FAQ describes it in "redirect http to https and HSTS". You use the X-Forwarded-Proto instead of the HTTPS variable because of how NFSN's virtual hosting is setup.

RewriteEngine on
RewriteCond %{HTTP:X-Forwarded-Proto} !https
RewriteRule ^.*$ https://%{SERVER_NAME}%{REQUEST_URI} [L,R=301]

Turning on HSTS is as simple as adding the HSTS HTTP header. However, the description in the above link didn't work because my site's NFSN realm isn't on the latest Apache yet. Instead I added the following to my .htaccess. After I'm comfortable with everything working well for a few days I'll start turning up the max-age to the recommended minimum value of 180 days.

Header set Strict-Transport-Security "max-age=3600;" 

Finally, to turn on CSP I started up Fiddler with my CSP Fiddler extension. It allows me to determine the most restrictive CSP rules I could apply and still have all resources on my page load. From there I found and removed inline script and some content loaded via http and otherwise continued tweaking my site and CSP rules.

After I was done I checked out my site on SSL Lab's SSL Test to see what I might have done wrong or needed improving. The first time I went through these steps I hadn't included the chain file which the SSL Test told me about. I was able to add that file to the same files I had already previously generated from the Let's Encrypt client and do another NFSN assistance request and 15 minutes later the SSL Test had upgraded me from 'B' to 'A'.

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4 people are living in an isolated habitat for 30 days. Why? Science!

Feb 1, 3:27


This 30 day mission will help our researchers learn how isolation and close quarters affect individual and group behavior. This study at our Johnson Space Center prepares us for long duration space missions, like a trip to an asteroid or even to Mars.


The Human Research Exploration Analog (HERA) that the crew members will be living in is one compact, science-making house. But unlike in a normal house, these inhabitants won’t go outside for 30 days. Their communication with the rest of planet Earth will also be very limited, and they won’t have any access to internet. So no checking social media kids!

The only people they will talk with regularly are mission control and each other.


The crew member selection process is based on a number of criteria, including the same criteria for astronaut selection.

What will they be doing?

Because this mission simulates a 715-day journey to a Near-Earth asteroid, the four crew members will complete activities similar to what would happen during an outbound transit, on location at the asteroid, and the return transit phases of a mission (just in a bit of an accelerated timeframe). This simulation means that even when communicating with mission control, there will be a delay on all communications ranging from 1 to 10 minutes each way. The crew will also perform virtual spacewalk missions once they reach their destination, where they will inspect the asteroid and collect samples from it. 

A few other details:

  • The crew follows a timeline that is similar to one used for the ISS crew.
  • They work 16 hours a day, Monday through Friday. This includes time for daily planning, conferences, meals and exercises.  
  • They will be growing and taking care of plants and brine shrimp, which they will analyze and document.

But beware! While we do all we can to avoid crises during missions, crews need to be able to respond in the event of an emergency. The HERA crew will conduct a couple of emergency scenario simulations, including one that will require them to maneuver through a debris field during the Earth-bound phase of the mission. 


Throughout the mission, researchers will gather information about cohabitation, teamwork, team cohesion, mood, performance and overall well-being. The crew members will be tracked by numerous devices that each capture different types of data.


Past HERA crew members wore a sensor that recorded heart rate, distance, motion and sound intensity. When crew members were working together, the sensor would also record their proximity as well, helping investigators learn about team cohesion.

Researchers also learned about how crew members react to stress by recording and analyzing verbal interactions and by analyzing “markers” in blood and saliva samples.


In total, this mission will include 19 individual investigations across key human research elements. From psychological to physiological experiments, the crew members will help prepare us for future missions.

Make sure to follow us on Tumblr for your regular dose of space:


Tweet from David_Risney

Jan 27, 9:57
FCC proposes replacing cable card with software based equivalent. Would be amazing if it could happen. …

Retweet of xeni

Jan 25, 1:18
UK film censors forced to watch a 2-day long movie of paint drying cc: @greatdismal …

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Jan 12, 12:53
Chewbacca... his arms open.

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Jan 2, 6:04
Adware uses Fiddler libraries to proxy HTTPS traffic and inject ads (cc @ericlaw) …

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2015 Dec 21, 5:26
Succinct explanation of the Dual EC travesty as realized in the Juniper debacle. …

Retweet of unconed

2015 Dec 19, 5:41
Here's an elaboration of that last thought. Mathematicians are insane. Q.E.D.

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Big drones with nets capture smaller drones in Tokyo no-fly zone. But where does it end?! …

Retweet of Grathio

2015 Dec 4, 8:02
Good news! the patent on the Space Shuttle has expired. Go and build, royalty free! …

Tweet from David_Risney

2015 Nov 3, 7:52
Setting up 2FA on all my accounts gives off temporary illusion that I've really got my shit together.

Retweet of SwiftOnSecurity

2015 Nov 1, 10:18
"Should driverless cars kill their occupants to save pedestrians?" Humans will evolve to walk in packs for protection. Time is a circle.

Retweet of PattenPending

2015 Oct 9, 6:53
For #inktober today I did my interpretation of @neilerdude's Maxwell Keeper: the Time Keeper from @ComedyBangBang

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2015 Sep 22, 9:35

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2015 Aug 16, 8:05
The movie "Hackers" was released 20 years ago tomorrow. Here is the theatrical trailer which punked theater goers. …

Tweet from David_Risney

2015 Aug 16, 9:56
Who is stealing their trash bins? I still require closure from this excellent episode. …

Retweet of radix42

2015 Aug 9, 8:55
She said "daddy I can't download this" and I looked and said "I'm so sorry we're living in a @doctorow novel" and had to explain :-(
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