Category Archives: Science, Space, Technology

NASA Tethered Satellite: Broken Tether Analysis

Here are a couple photos of me from 1996 wearing a NASA “bunny suit” while working the failure analysis of the broken tether on the Tethered Satellite System re-flight (TSS-1R) that had recently returned from orbit on Space Shuttle mission STS-75.  I was taking magnified photographs with a fancy high-tech digital SLR camera through an old-school benchtop microscope.

These photos were taken in the Operations & Checkout (O&C) Building hi-bay which is a clean-room environment up on the work platforms, because the workers are adjacent to flight hardware.  The blue bunny suits look kind of funny, but they help keep the flight hardware pristine and help keep our hair and our skin flakes from falling onto the flight hardware.

The Tethered Satellite System was a pretty interesting experiment.  The theory was that we could extend a long electrical wire while orbiting the earth and that long wire would cut through the earth’s magnetic field lines and generate electricity.  The tether on this experiment was nearly 13 miles long!  Wow!

This tether experiment first flew in 1992 on Space Shuttle mission STS-46, but had trouble deploying.  It deployed less than a thousand feet out from the orbiter before it jammed.  But it got a second chance and flew again in 1996.  The deployment during the re-flight mission went well and was nearly complete … about 95 percent complete … when the tether broke and the experiment was over.

The broken tether was reeled back in and was brought back to earth for analysis.  The task was to find out if the tether was mechanically broken, like from too much tension, or maybe from a micro-meteor impact.  Or whether the tether was broken due to an electrical arcing event, such as an over-current.

The final analysis showed that it was an electrical overload.  But the reason for the excess current was pretty interesting and took some detective work.  Around the outside of conductor was a clear Teflon insulation layer which is basically a plastic.  It’s similar to the white plastic insulation layer around the center wire in a coax cable.

It was determined that this plastic Teflon layer was “breached” and electrical arcing occured between the tether’s conductor and the gantry system that was deploying the tether.

One possible cause of the break in the insulation was “foreign object debris”, which is NASA-speak for something that does not belong there.  We take great efforts to keep flight hardware pristine and clean.  But if a loose wire or something stiff or sharp got into the cogs of the deployment mechanism and punctured the insulation, that could have caused the electrical short.

Another possible cause was a simple manufacturing defect and subsequent quality control miss.  Investigators showed that trapped air in the Nomex core could have leaked out through tiny pinholes in the plastic Teflon insulator and caused an electrical plasma arc due to the high voltages involved.  The experiment was generating about 3,500 volts and about half an amp of current when the failure occurred.

Even though the tether broke and the experiment could not be completed, it was a partial success and lots of data was collected during the deployment before the failure.  So it wasn’t a total loss.

Thanks for your interest!

Kurt

My Trip to Krakow, Poland: The Food

I just returned from a trip to Krakow, Poland last week where I was speaking at a software developer conference.  I posted details of that experience here.  I also posted details about my sightseeing experiences here.  This post, however, is dedicated to all the wonderful food that I ate while I was there.  The lighting was not great in most of these restaurants, so I will apologize in advance for the quality of these photos.

The food during the 2 conference days was catered and it was all very good, but I didn’t take notes nor take any photos of those particular meals.

The conference organizers took all the speakers out to dinner the evening before the conference started.  They took us to a bistro and restaurant called Kogel Mogel which was just a couple of short blocks from the central town square.

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We stared with a wonderful sour rye soup (Zurek or zur) with mushrooms.  It also had some sausage in it and also some hard boiled egg.  I apologize for not getting a photo of it.  It was super tasty.  Different from anything I’ve ever had before.  It’s made with fermented or soured grains.  I liked it a lot.

Our main course was a chicken schnitzel with a mushroom sauce and mild peppercorns.  A schnitzel is a meat that’s thinned by pounding and is then coated with flour, egg, and bread crumbs and then fried.  We also had potato dumplings (kluski slaskie) which were pretty good.  Especially when dipped in the mushroom sauce from the chicken.

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For dessert we had a creme brulee, which was to die for.  A week later, my mouth still waters when I think about it.

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The next morning, which was the first morning of the conference, I ate breakfast down in the hotel lobby.  I stayed at the Novotel Krakow Centrum hotel, which was just off the Vistula river, across from Wawel Castle.  It’s a very nice and modern hotel.  The breakfast buffet was quite impressive and it was included in the cost of the room.  I didn’t eat too much, though because I don’t eat heavy breakfasts and I didn’t want to be weighed down at the conference.

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I should have taken a photo of the entire spread, which was quite impressive.  I did get a photo of the meats and also of the cheeses, though.

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That evening I found a great little authentic old country restaurant, also within a couple short blocks of the central town square.  This family friendly restaurant is called Morskie Oko and it is in the style of an old Highlander’s Inn.  While I was eating, live entertainment included singing and dancing Highlanders in full costumes, plus live musicians.

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The food was really incredible here.  I started with an appetizer of baked prunes wrapped in bacon fat.  Now if you like your bacon cooked well done and crispy, this dish is NOT for you.  This bacon was very thick … probably hand carved … and it was very moist and greasy.  It was so yummy, though.  I could barely even taste the prunes through all that bacon fat.  Mmmmmmmmmm.

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Next I ordered the sauerkraut soup which had sauerkraut and potatoes and also a small rib in it.  I love sauerkraut, so this soup was delicious!  It’s sour, but it’s a different kind of sour than the fermented rye grain soup I’d had the previous night.

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For my main dish, I had the boar loin in red pine mushroom sauce.  Oh.  My.  Gosh.  This boar meat was quite tender.  Similar to a nice steak.  It had a wild taste but not too wild.  It was amazing.  It had grill marks on it, so it was cooked, at least partially, over an open flame.  And the red pine mushroom sauce was really great.  It tasted a lot like a red wine sauce, but I’m not sure whether that taste only came from the red pine mushrooms or not, since I’ve never had those before.

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The portions were not too big, so I actually had some room left for dessert.  So I ordered a walnut ice cream sundae with hot fudge, whipped cream, and roasted hazelnuts.  I hadn’t planned on eating the entire thing, but it was so good.  I couldn’t help myself!

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And here is my breakfast on my second morning in the hotel lobby.  Meat, cheese, and a bit of scrambled eggs.  The breakfast of champions!

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That evening I was tired from the conference, so I just stayed in and ordered room service.  This is just an appetizer of shrimp with garlic and chilli, but it was all I needed that evening.  It was very yummy.  We had snacks all day long at the conference, so I wasn’t exactly starving at dinner time.

I also got this warm soft brownie and ice cream dessert from room service.  So warm.  So soft.  So fudgy.  It was delicious.

The next day was Saturday, and the conference organizers took us speakers out for lunch at a nice restaurant called Miod Malina, which again, was only a couple short blocks from the central town square.

This is the Bruschetta, which was very simple and very good.

And I ordered the sour rye soup again, since I loved it so much a couple days earlier.  Many restaurants, including Miod Malina, serve it in a bread bowl.

Miod Malina put a lot more meat in this sour rye soup than did Kogel Mogel, but the Kogel Mogel version was more sour (sour being good).  Both were very good in their own way.

I finally got to dig into some good old fashioned Polish pierogis, also known as dumplings.  The ones I ordered were fried meat pierogis, but the restaurant also bakes them and also has a fruit version and a potato/onion version.  These meat pierogis had 3 different meats inside.  Some had pulled pork.  Some had beef.  And some had veal, I think.  They were really awesome!

This was not my plate … it was one of the other conference speakers … but I had to take a photo of it.  I had seen several people eating these while I was in Poland and it looks really good.  It’s veal knuckle, otherwise known as veal shank.

That same evening, I had my dinner at the Wesele Restaurant, which was directly in the town square.

This time I tried the sauerkraut and mushroom fried pierogis and they were so stinking good!  I could eat 4 or 5 plates of these things!

I had ribs with plum sauce which was pretty good, although I don’t think plums are really my thing.

And I also ordered fried cabbage as a side dish.  I’d never had this before and it was mild, but it was very good.  My pee smelled like sauerkraut for the next 2 days, and I think it might have been from this particular dish.  Although, I guess it could have been from other  dishes I’d had containing sauerkraut.

My last full day in Krakow was Sunday, and I had lots of sightseeing and shopping to do, so I went straight to the central town square and ate breakfast at this little handmade doughnut shop called Krakowskie Paczki, which means Krakow Packages.  It’s a popular little shop as there was quite a line of customers.

They also sold waffles.  So I got a jelly filled doughnut and a waffle with blackberry jam.  The filling in the doughnut was different than anything I’d ever tasted and maybe it’s an acquired taste, but the doughnut itself was spectacular.  And the waffle was quite good too.  And yes, I had Coke for breakfast.  Hey, I was on vacation!   🙂

This entire day went by pretty fast since I was trying to experience the entire central town square and also buy a bunch of souvenirs, so I didn’t actually eat lunch.  And when dinner time rolled around, I wasn’t exactly starving either.  So I decided to just get an appetizer.  I went to a fancy restaurant on the square called Szara.

I had heard a lot about Beef Tartare or Steak Tartare, and I had seen lots of people eating it here in Poland, so I decided to try it.  Even though it is raw ground beef and raw egg yolk.  It was actually pretty good.  I was not a fan of the smoked herring or whatever that fish is on the plate.  But when I mixed all the other ingredients together, it was an interesting and nice little treat.  Going around the plate, there was raw chopped onion, chopped tuna, I believe, chopped pickes, butter, and the sauce tasted like a mild honey mustard.

I finished my small dinner meal with an ice cream of sorts called Pistachio Semifreddo with caramel and chocolate sauce.  It’s very light, like a frozen mousse.  A pretty fancy dish.

Well, that about covers all the awesome food I ate while in Poland! Tomorrow I’ll publish a blog post detailing the trip in general along with some of my random observations about Krakow, Poland.

Thanks for your interest!

Kurt

My Trip to Krakow, Poland: The Sights

I just returned from a trip to Krakow, Poland last week where I was speaking at a software developer conference.  I posted details of that experience here.  This post, however, is dedicated to the sightseeing I was able to squeeze in while I was there.  I only had my iPhone 5S on this trip, so I will apologize in advance for the quality of  some of these photos.

This photo sort of shows the typical countryside in Poland.  Huge historic-looking castle looking structures right next to modern looking apartments right next to small modest cottages.

The Wawel Castle and the Vistula River are both important landmarks of Krakow.  The river is the longest and largest river in the whole country and it snakes through the entire city.  The castle sits prominently on top of Wawel Hill and is one of the most historically and culturally important sites in all of Poland.

Here’s a close up photo of Wawel Castle at night.

And here is another photo at night, but from across the river.

In the center of Krakow city is Rynek Glówny, which means “main market” or “main square”.  It’s a large medieval town square, dating back to the 13th century, surrounded by palaces & churches.  It’s a wonderful area of town and it’s a huge draw for locals and for tourists both during the day and at night.

Here is a photo of Wieza Ratuszowa, or “town hall tower”, which is a renovated Gothic tower that used to be just one part of the town hall, but is now a museum.  I regret that I did not have time to visit any of the museums in town while I was there.

This building, also in the middle of the town square is The Cloth Hall which is a Renaissance-style market hall lined the entire length with stalls of locals selling goods.  It also contains a museum.

The main visual Gothic standout of the town square, though, is St. Mary’s Basilica, which is a huge Catholic church with 2 tall asymmetrical towers.  Every hour, a trumpet signal is played from the top of the taller of the two towers. The tune breaks off in mid-stream, to commemorate the famous 13th century trumpeter, who was shot in the throat while sounding the alarm before the Mongol attack on the city.

This photo fails to show the size of these huge doors since no-one is in the photo for scale.

The entire perimeter of the town square is lined with outdoor seating for the various restaurants and bars that make up the majority of the storefronts.

Street performers sprinkle the town square.  All day and all night.

And also the side streets leading to and from the town square.

This is sort of random.  Meet Polish banjo playing Abe Lincoln talking on his smart phone!

I’d like to see what’s under the hood of this street performer’s act.  She just sat there motionless.  What exactly is holding her up?  She looked very stable with no noticeable wobble.  It’s a great trick.

Musicians were by far the most popular choice of street performers.  Both groups and soloists.

There were lots and lots of horse drawn carriage rides to choose from in the town square.

Here is what the inside of The Cloth Hall looked like.  Lots of trinkets and jewelry for sale.

The streets of Krakow were very interesting.  Lots of 2 or 3 story buildings of various architecture styles.  Lots of narrow streets.  Lots of odd angles and irregular streets.

Some buildings are quite colorful.  In this photo you can see the wires that are used to power the street cars, which were sort of a cross between a bus and a train.  They looked a lot like a bus.  But they ran on a train track in the middle of the road.

This photo shows a typical street leading towards the town square.  St Mary’s is in the distance.  The streets leading to the square were full of tourist shops selling trinkets, jewelry, food, etc.

There were a few 3-dimensional bronze maps like this in the notable historical areas.  Very cool.   Wawel Castle is on the far end and the Vistula river is on the other side of it.  In the middle you can see St Mary’s and The Cloth Hall and the Town Hall Tower.

We took a short 30 minute trip down the road to tour the Wieliczka Salt Mine.  It is really cool.  It took about 3 hours to tour it and they told us we had only seen about 1 percent of the whole mine.  It’s huge!  And it’s all hundreds of meters below the surface!

When it stopped production of salt in 2007 it was one of the world’s oldest salt mines in production.  Within the mine there are lots and lots of statues that are carved out of rock salt and also many rooms and even chapels.  Here is a photo of a room with large logs holding up the ceiling.

This photo shows a long mine with a railway in the middle for hauling out the salt.

The walls and ceiling and floor of the mine are all rock salt.  The salt looks and feels like stone or marble.  It’s very hard stuff.  You can make out its crystalline structure in this photo.  The salt is far from pure when it’s mined.  It requires processing into table salt.  I don’t recall the details, though.

This is one of many many statues on display inside the mine that are actually carved out of rock salt.  Remember, it’s very hard … like marble.

This is pretty crazy.  It’s a huge chapel.  Underground.  Carved in the rock salt.  Walls, ceiling, floor are all rock salt.  And the stairs!  People pay tens of thousands of US dollars to have weddings in here!

Another photo of the chapel with alter detail.  Everything is rock salt!

The most pure rock salt is actually clear.  Crystal clear.  So they carved these chandelier crystals out of that pure salt.

Here is a close up photo of some of the relief sculptures carved into the walls of the cathedral.  This photo was probably a couple feet high.

Occasional statues like this one of Mary are carved out of pure salt which is clear and looks really cool with lights inside.

There are a few underground rivers and lakes inside the mine that are completely saturated with salt.

I have a lot more photos, but I wanted to try to minimize the selection and try to not overload my readers.  Tomorrow I’ll publish a blog post about all the wonderful food that I was able to experience during my short time in Krakow, Poland.

Thanks for your interest!

Kurt

My Trip to Krakow, Poland: The Conference

This past Friday I had the honor of giving the morning keynote presentation at the 6th annual DevDay software developer conference in Krakow, Poland!  Here is the website!  (Check it out!  It actually has my face on it!)

http://devday.pl/

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This conference is sponsored by ABB Automation Group, which is a huge industrial robotics company in Europe.  They also manufacture industrial electronics, industrial control systems, and industrial power systems.  They’re kind of a big deal.

DevDay is a 2 day conference for software developers that is limited to only 500 attendees, so it’s a small and intimate event.  The speakers are truly able to interact with the attendees and networking at this event is highly encouraged by the organizers.  During the 2 days, DevDay packed in 4 separate keynotes and a total of 30 technical sessions!  It was a really great event!  The organizers did a wonderful job!

The DevDay organizers feel strongly enough about using only live speakers, that they pay for their airfare,  hotel,  food, and also ground transportation.  The venue for the conference was a movie theater and the screens were enormous!  Can you imagine giving a keynote address on a screen like this?!?!?

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By the way, that’s Zach Holman in the photo getting ready to give his keynote.

My keynote presentation was called “We Are The Explorers!” and it presents the story of the great westward expansion by the early American pioneers.  It describes how difficult the task was and how great the payoff was.  It then explains how the settlers had to live off the land to survive and then it transitions to NASA’s space exploration plans and how we will have to live off the land too.  Then it shows off a bunch of living-off-the-land technologies (ISRU) that are being developed by NASA to support future planned long term human exploration missions on Mars.

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Here is the official DevDay 2016 video of my keynote on YouTube:

My keynote presentation was very well received and I got a ton of compliments from both attendees and from other speakers!  One of the biggest compliments I received was from another speaker who speaks at a lot of conferences all over the world.  He said “You rehearsed the *bleep* out of that, didn’t you?”.  Yes, I did rehearse the *bleep* out of my keynote during the weeks leading up to the conference.  I guess it paid off.  🙂

I also gave a technical presentation called “NASA’s ant-inspired Swarmie robots” which gives the background of the Swarmie project and describes the software technologies that we used as well as various challenges and solutions that we encountered along the way.

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Here is the official DevDay 2016 video of my technical presentation on YouTube:

Full videos of all the keynotes and talks, are posted on the DevDay YouTube channel:

https://www.youtube.com/user/ABBDevDay/

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There are tons of great professional photos from the event posted on their Flickr account too:

https://www.flickr.com/photos/96896358@N04/albums

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Here are my favorite professional photos, though:

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One of the highly experienced professional speakers at this conference paid me a huge compliment after my keynote when he asked me how long I had been a Tech Evangelist for NASA.  He didn’t know that this was my very first professional conference keynote speech.  Sure, as a NASA employee, I speak to students a lot.  And I give technical presentations to co-workers and to managers all the time.  But the keynote at a conference like this.  Never before.   I’m honored to have been invited to come speak at this amazing conference!

Also, this was the first time I’d ever left the United States.  I had a really great experience!  Tomorrow I’ll publish a blog post about the sightseeing that I was able to squeeze in during my short time in Krakow, Poland.

Thanks for your interest!

Kurt

P.S. Here’s a selfie of me standing outside the venue soaking up some sun in an effort to counteract some of my jetlag.

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P.S.S. And here is a photo I took of Russ Olsen giving the closing keynote which was a very inspirational story about the race to land a man on the moon!

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P.S.S.S. And finally, here is just a photo of me striking a pose after the conference was over.

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Kurt’s review of “The Martian” by Andy Weir

Oh. My. Gosh.

I love, love, love this book!

Okay, so I’m a nerdy NASA engineer. Of course I loved it.  But I know all you non-nerdy folks will also love this book.  And here’s why:

It’s interesting & engaging

It’s a survival story set in one of the harshest locations imaginable.  So many things can go wrong … and so many of them do go wrong.  Every step of the way.  It’s nearly constant edge of your seat entertainment.  Add in some NASA politics and a few personality conflicts and you’ve got yourself a real pager turner.

It’s funny.  No, it’s hilarious

The narrator … the astronaut who gets stranded on Mars … has a terrific sense of humor throughout the entire book.  He’s quite a character and his personality stays upbeat despite his less than ideal circumstances.  Much of the narration is of him logging his daily activities into a computer system in which he has no idea whether anyone will ever read or not.  He’s basically talking to himself for much of the book and it’s quite humorous.

It’s technical, but not in a bad way

There’s a constant stream of problem solving throughout the book.  But I don’t think it will make your eyes roll back in your head.  Most of the time the details are given in a way that the layperson can understand.  Sometimes the narrator even “dumbs” down the technical details for the reader.

It’s real

Well, mostly real.  This is science fiction, but it is not your typical far-fetched or far-futuristic science fiction.  Much of this story could occur today using technology that we actually use today or technology that we are developing and testing today for use on future Mars missions.  Most of the engineering solutions are also real and possible today using current technology.  There is very little hand-waving here.  And it is very satisfying.

Note: This book is not for kids.  The narrator … the astronaut who gets stranded on Mars … curses like a sailor throughout the entire book.

I highly recommend this book.  It’s a very interesting and engaging read that is difficult to put down.  It’s entertaining for engineers and non-engineers alike.

Click below to order the book for yourself.  You can buy it in paper or digital formats from Amazon, the most popular online store in the world!

Thanks for your interest.

Kurt