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We are a podcast community looking to help out a friend in need. Recently, our friend, 5150, lost his home that he shares with is father to a house fire. Both were able to make it out ok, but he is in the hospital with 2nd degree burns. His father is elderly and has been moved to assisted care while he is recovering.

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Latest Shows

hpr1597 :: Extravehicular Activity

NASA guidelines for EVA from spacecraft are detailed and painstaking, not so films.

Hosted by Steve Smethurst on 2014-09-16 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (0)

EVA - The Rules for Extravehicular Activity

Here I dip into the NASA experience of and rules for Extravehicular Activity, prompted at first by watching a film called The Europa Report, directed by Sebastian Cordero (2013).


While I have some gripes about the film, I was impressed by its general failfulness to the science

  • It thought to find life on Europa, a moon of Jupiter considered by real exobiologists and planetary scientists to be a good candidate
  • Neil deGrasse Tyson made a cameo appearance
  • The portrayal of Europa's geography and character
  • Having to drill through the ice to get at the sea below
  • The behaviour of the crew as scientists and engineers

Science consultant on the film was Kevin Hand, an astrobiologist and expert on Europa at NASA's Jet Propulsion Laboratory

To my mind, the scientists were behaving like scientists and the engineers behaved like engineers. To follow along it might help to recall their names

  • Captain - Willam Xu
  • Pilot - Rosa Dasque
  • Chief scientist - Daniel Luxembourg
  • Marine biologist - Katya Petrovna
  • Junior engineer - James Corrigan
  • Chief engineer - Andrei Blok

All was going scientifically until the director drove the plot forward with two EVA incidents

EVA-1 : Flash back episode, engineers James and Andre go out to fix a failed communications circuit

  • Andre rips his suit
  • James gets squirted with rocket fuel
  • Only one astronaut survives

I have problems with this becuase it's just too clumsey for trained professional astronauts. Where are the decontamination procedures, the tethers, the special tools?

EVA-2 : Down on the surface, Marine biologist Katya decides to walk out alone

  • Tourtured debate in the ship
  • Of four able and expendable crew members, none go with her
  • Katya does not come back alive

With this I am shouting at the screen "No Way! Where's the fracking operating manual? No one goes EVA on their own"

So, that is why I researched the NASA rules for Extravehicular Activity. And I found that none of these events would have happened the way they were shown, had the crew, who were so professional in every other way, followed the NASA procedures.

The two astronauts issue

  • The most recent occasion where an astronaut went solo EVA was in 1971, when David Scott stuck his head out of the airlock of Apollo 15.
  • Most recent before that was in 1966, when Buzz Aldrin went EVA from Gemini 12 (Gemini craft only had two crew).
  • Since 1971, there have been 358 space walks and every single one has had two crew.
  • I found no written regulation, but de-facto, nobody leaves the spacecraft alone.

NASA procedures

NASA documents on the internet discuss in exhaustive detail all condiderations for EVA. What I present is a cherry-picked handful. I could not cover all of it

  • reasons for EVA
  • alternatives
  • planning
  • hazard mitigation
  • procedures for safe conduct
  • fall-back procedures
  • failure handling
  • accident control

International Space Station (ISS) EVA Procedures Checklists

  • Presuming that all the equipment maintenance checks, and readiness checks have alread been done
    • 30 minutes of Airlock preparation and testing
    • 30 minutes of changing components for the suit to fit the astronaut
    • 170 minutes of EVA-Prep
  • Then you are ready to depressurise and leave the airlock
  • EVA might last 2 - 8 hours
  • Post EVA
    • 30 minute procedure to take the suit off
    • 10 minute procedure to disconnect internal equipment
    • Recharge & maintain the Extravehicular Mobility Unit (EMU)
    • Clean & maintain the Suit

Although this podcast is about EVA, it does reference the science in a film that I enjoyed and respect very much, so here is a gem that I only came across while researching the landing site. In the scientific journal Nature, Volume 479, 16 November 2011, Britney Schmidt et al, of University of Texas, Austin, published a paper titled "Active formation of 'chaos terrain' over shallow subsurface water on Europa." In the paper these authors suggest that in the Conemara zone of the Chaos Terrain, an area on the surface of Europa, the ice may be as little as 3 km thick. Then in the film the Conemara Chaos was the targetted landing zone and the drill broke through the ice at a depth of 2800m.

Well there is one more thing that the podcast says, but it is the ultimate spoiler. So if you have not already listened to the podcast, I highly recommend that you watch the film first.


hpr1595 :: 37 - LibreOffice Calc - More Financial Functions

A look at financial functions and constructing a mortgage repayment schedule

Hosted by Ahuka on 2014-09-12 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: LibreOffice | Comments (0)

We take a look at a number of related financial functions in this episode, and discover that they are strongly related by using the same variables over and over. We construct a Mortgage Repayment Schedule, and look again at the principles of good spreadsheet construction.

hpr1594 :: Steam and wine with linux

How to coax a windows-only steam game to work under steam in GNU/Linux.

Hosted by Andrew Conway on 2014-09-11 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (0)

This isn't about my worshiping of Bacchus by playing games on linux in a sauna (that's for a future show) but instead about getting a Windows-only Steam game to work on a recent 64 bit linux distro. I'm using Slackware, but I suspect the pitfalls and solutions I encountered would be similar on other distros.

Links relevant to this adventure:

hpr1593 :: Why C++?

Introduction to the C++ programming language main features

Hosted by garjola on 2014-09-10 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: Programming 101 | Comments (1)

In this episode, Garjola presents the C++ programming language by introducing its main features for object orientation, generic programming and functional style.

hpr1592 :: An Open Source News Break from

Open source CMS, tools for making presentations, WikiProject Med

Hosted by semioticrobotic on 2014-09-09 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: NewsCast | Comments (0)

In this episode: Open source CMS applications go head-to-head, open source tools for making presentations, and WikiProject Med.


hpr1591 :: The Ultimate Cooking Device

Using a Weber grill to cook all your food.

Hosted by PipeManMusic on 2014-09-08 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (0)

Using a Weber grill to cook all your food.

hpr1589 :: KC MakerFair 2014

A rundown on all the cool things to see at the KC MakerFair 2014

Hosted by MrGadgets on 2014-09-04 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Comments (0)

Mr. Gadgets calls in another show and this time he has been to Kansas City Maker Faire.

Maker Faire: Kansas City celebrates things people create themselves — from new technology and electronic gizmos to urban farming and “slow-made” foods to homemade clothes, quilts and sculptures. This family-friendly event demonstrates what and how people are inventing, making and creating. It brings together Makers, Crafters, Inventors, Hackers, Scientists and Artists for a faire full of fun and inspiration.


hpr1588 :: HPR AudioBookClub-09-Down And Out In The Magic Kingdom

In this episode, the HPR_AudioBookClub reviews Down And Out In The Magic Kingdom by Cory Doctorow.

Hosted by HPR_AudioBookClub on 2014-09-03 and released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. Series: HPR_AudioBookClub | Comments (2)


In this episode, the HPR_AudioBookClub reviews Down And Out In The Magic Kingdom by Cory Doctorow. You can download this AudioBook for free (or voluntary donation) from and it's also available in just about every ebook format you can imagine on Cory's website and as a paperback through various booksellers. We found this AudioBook enjoyable and thought provoking. The general consensus that we seem to have reached is that while the book left the reader with many unanswered questions about the world in which the book was set, they are welcome questions. It's brain bending fun.

FiftyOneFifty (the link-king) found some cool links relating to the Haunted House and how it works. Check these out!

gigasphere wrote in to say,

I listened to this book in the space of a couple of days mostly. At first it took some time to get into but then was quite enjoyable, however in the second half I started to find it a bit hard going. The story is told exclusively in the first person (I think that's right) and as the story went on I found it quite difficult not having external points of view or reference. This is probably also due to good story telling as the main Character Jules is also getting frustrated and is increasingly isolated. The book was interesting and unique even before you got to the plot line and aspects of the world the characters were living in. I would recommend the book as an example of an interesting method of story telling and I'm keen to pick up the other big Cory Doctorow book, "Little Brother".

gigasphere's spoilers (Highlight to read)

From having read the wikipedia page on Cory I can see that Down and Out in the Magic Kingdom, which is Cory's first novel, seems to have a trademark extrapolation with our own reality. The concept of backing up you mind and being brought back from the dead in a clone seems an excellent example of hyper-our-reality at the moment, but to then have everyone capable of being online using implants is also amazingly realistic when you consider the almost boom in wearables going on and the ubiquity of smartphones. I am reminded of the xkcd comic where the guy was having a USB port implanted.
The whuffie aspect of the book which replaces money, reminds me a lot of the social media thing of being rated by how many 'followers' or 'likes' or may be even 'hits' you get. This also oddly reminds me of the download stats discussion on the mailing list at the moment.
I'm not sure I'll add much to the overall discussion of the book from here as my no spoiler summary really rounds up the book for me. I would have liked to have a broader telling of the story, particularly from Lil's perspective, but the restrictions placed on the story also work to make it great, in that you are forced, as in real life, to view the world through only one person's eyes.


We think you'll agree that the HPR_AudioBookClub really showed up for this one and they brought some all-star beverages. Please enjoy this episode responsibly.

  • x1101 just wanted to make us all jealous. He brought a Lagunitas Imperial Stout to our little party and enjoyed it as much as any of us would have.
  • FiftyOneFifty was slightly disappointed by his German style Doublebock, FIREMAN'S BREW: Brunette. He says it's an unprepossessing brew, but perhaps worth it for fans of beer made with chocolate malts. Not very sweet for a dopplebock, and without much hops note except for a slight spicy kick, despite a general thinness in the flavor, it has enough cocoa flavor to satisfy fans of beers made with chocolate malt, at least until they find a better one.
  • The planets aligned and dictated that Semioticrobotic bring his favorite tea, Ginger Twist by Mighty Leaf, to our little show. It's a zippy but soothing herbal tea (technically, then, a tisane) that combines strong ginger flavors with lemon-grass and mint.
  • pokey's limited run microbrew, Saison du Buff, is a collaboration between three breweries; Dogfish Head Ales, Stone Brewing Co., and Victory Brewing Company. It can be purchased from any of the three, and if you're lucky enough to find some you should do exactly that. pokey described it as a little spicy, very complex and really enjoyable. Big thumbs up.
  • pegwole was worshiping at the porcelain vessel. No, not THAT porcelain vessel... The good one. The one that's used to serve Coffee!
  • This month gigasphere wrote in to say,
    "It's hot over here in the UK South East at the moment (25-30 degrees Celsius, yes that's hot for here!) and I'm swamped with work so I have a really boring Apple and Elderflower Juice for my drink this month. I have an Ale on the shelf that I haven't tried before but will save that for next time round when I should have a more manageable workload. On the plus side my juice is really cold and refreshing with a really strong and pleasant flavour (sic)2. It's a fresh juice and so has been kept refrigerated. Now everyone can stop laughing1 at me and get back to their proper drinks!"
  • Rather than simply reviewing a beverage like the rest of us, Thaj (attention seeker that he is) risked his life on the show by ingesting a potentially lethal amount of Dihydrogen Monoxide! The HPR_AudioBookClub does not condone this type of risky behavior, and if you are entertained by it, then you're probably a bad person.


Revolution Radio by Seth Kenlon


Street Candles by David Collins-Rivera

We're really excited about these two AudioBooks because both of these authors are HPR community members! We're assigning both at once because one is pretty short, and one is pretty long. We were a little worried that people might not finish Street Candles in time to participate, and we think this scheme may buy participants the time they they/we need.

Seth Kenlon's personal profile page:
Seth Kenlon's HPR correspondent page:

David Collins-Rivera's personal blog:
David Collins-Rivera's HPR correspondent page:


Our next book club recording will be 2014/08/12T23:00:00+00:00. If you'd like a Google calendar invite, or if you'd like to be on the HPR_AudioBookClub mailing list, please get in contact with us on the HPR mailing list 'hpr at hackerpublicradio dot org'


Thank you very much for listening to this episode of the HPR_AudioBookClub. We had a great time recording this show, and we hope you enjoyed it as well. We also hope you'll consider joining us next time. Please leave a few words in the episode's comment section.
As always; remember to visit the HPR contribution page HPR could really use your help right now.

The HPR_AudioBookClub

P.S. Some people really like finding mistakes. For their enjoyment, we always include a few.

1: The HPR_AudioBookClub doesn't laugh at anyone for reviewing tea, nor any other drink. We intentionally call the segment a "beverage review," not a "beer review" so that no one should feel alienated. Also because some of us drink wine.

2: The HPR_AudioBookClub does laugh when people try to spell flavor with a "u"