Loki Lego Launcher 3.0 Video


Lessons Learned 3.0

We are finally home after a 4206 mile road trip, and 18.5 hours of driving from Wyoming. That gave us a lot of time to digest and talk about our incredible eclipse launch experience, and all the lessons we learned from Loki Lego Launcher 3.0. This is what we came up with on the car ride home.

2017-08-24 08.02.04

Don’t make last minute changes unless you test

We were given the opportunity to attach an additional GPS tracker to our payload. We attached it suspended in a gimble (sp) the day before launch. We didn’t think it through all the way and consequently our launcher was unstable and spun. When the balloon burst, the gimble swung and knocked our main GoPro over, causing a large portion of the frame to be covered by wood.

Learn from experts; Mentor others

For this launch, we got to work with the Montana Space Grant Consortium (MSGC) and Sent Into Space, which is a commercial ballooning company from England. Two experts in particular spent time with us: Jen Fowler, the assistant director of the MSGC who organized everything and helped us with all phases of our launch, and Dr. June Wang, an atmospheric scientist from SUNY, who talked to us about analyzing data and calibrating instruments. We learned a lot from Chris and Alex from Sent Into Space, who have done over 300 balloon launches! We hope that someday we could be as great role models to others as these mentors have been to us.

Being part of a team

We felt really welcomed as members of the MSGC team. They helped us in all aspects of our launch, from pre-launch testing, to fill calculations, to providing us with additional supplies, to balloon fill, to the launch itself, to helping with the NASA microbes, to helping coordinate recovery. This launch would’ve been a lot different if it was just our family.

Something that really stood out to us was after a difficult recovery involving a 2 1/2 hour hike through cow pastures and feeling disappointed about our solar panel wire, we came back to camp to people who genuinely cared and understood how we felt about our results. That made us feel warm and fuzzy and supported and we appreciated being part of a team.

2017-08-24 08.02.15

Test the simple things as well as the complex

When we recovered we found that one of our solar wires had come loose. When we were testing, we had focussed on the electronics and forgot about the mechanics. We hadn’t checked to see if the wires were all connected. Because of this, we didn’t collect any solar data at all. Next time, we need to check even the simplest things.

Be extra prepared

Ms. Fowler not only taught us a lot but also had a lot of equipment we didn’t think we needed. In previous launches, we’d relied on Internet access to receive our APRS signal. Since we had very limited Internet access for this launch, Ms. Fowler lent us a portable Ham Radio we could use to test our APRS. She had extra helium and extra balloons! It was impressive to see how prepared she was for any contingency.

Equipment failures happen

When we put our data into graphs we saw that our pressure data was completely crazy. Instead of a smooth curve it was jagged and inconsistent, leading us to believe our pressure sensor was faulty.

Also, both of our GoPros turned off well before we ran out of battery. When we looked at the video footage, the GoPros turned off at -60 degrees C, the coldest temperature in all our launches. We didn’t insulate the GoPros because in previous launches we had never reached that temperature!

2017-08-24 08.02.46

A straight line is not always the fastest distance between A and B

When we were retrieving our launcher we walked in a straight line towards our landing coordinates. To do this, we had to climb a number of seemingly endless ridges, and only later realized that on the other side of us was relatively flat ground. Our hike back to the car was was a lot faster than the hike in because we walked around the ridges.

Follow your own advice

A few days before launch, we told ABC’s Good Morning America, “Even if something goes wrong, which will happen, just keep on trying.” After we recovered the launcher and viewed the footage and data, we were a little bit disappointed because a few things had gone wrong. When we were reminded of what we had said a few days earlier, we had to laugh at ourselves because we had forgotten our own advice.

We had a fantastic eclipse launch experience, and as you can tell, we learned a lot of lessons from it!

Eclipse Mission Debrief: Loki Lego Launcher 3.0

Our Goals

When we were planning this launch, we had two goals:

1. To capture footage of the moon’s shadow on the earth.

2. To capture and analyze data from our flight computer and solar panel as they pass through the solar eclipse.

Well, for Goal 1, here are some images Dad pulled from the two GoPro cameras:

eclipse totality 2eclipse totality 3eclipse totality 4

Based on these images, we can conclude that we got footage of the moon’s shadow on the earth. Check for goal one!

However, for goal two, when we retrieved our launcher, we found that there was a wire that had come loose on our solar panel. Fortunately, we had wired it in parallel and not serial, so our flight computer data was still good, but we didn’t get any solar panel data. Consequently it is incomplete for goal two.

Therefore, our overall mission results: partially successful.


By the Numbers

Height at highest point (apogee): 29,374 meters (96,371 feet) This wasn’t one of our goals but it was still really cool.

Total flight time: 1:35:42; launch to apogee: 1:10:30; apogee to landing: 25:12. These are our shortest times ever!

Temperature range during flight: -63C to 26C (-81F to 79F). It got pretty cold.

Distance between launch and landing sites:  46.7km (29 miles). It ended up landing in Nebraska!

Distance to hike between car and landing site: 1.5 miles (through ravines and thorny cow pastures) it took an two hours to hike there and back!

The shadow of the moon on the Earth!


Our flight computer data was good.  Our launcher made it up to over 96,000 feet, which is more than triple the height of Mt. Everest!

Our APRS data was incomplete because we had somebody else on the same radio frequency as ours.  We will want to think about this for future balloon launches when there are multiple launches in the area.

Our GPS data was as solid as ever, thanks to our SPOT Trace.  We wouldn’t have been able to find our launcher without the SPOT.

SPOT Trace

Our solar panel data was disappointing.  We didn’t capture any, due to the loose wire. We were unable to measure the impact of the eclipse on the solar power generated, which was a real bummer.

Alt-m vs Temp C
Altitude vs Temperature

Our Altitude vs Temperature graph showed the curve we have expected, where the temperature drops until the reaching the tropopause, and then it goes up until the balloon bursts. It also reached the coldest temperature on any of our launches at -63 degrees C. (-81 degrees F)

Alt-m vs Kmh
Altitude vs Speed

Our Altitude vs Speed graph is very similar to our previous launches, showing the lack of air resistance in the tropopause.

Alt-m vs Pa
Altitude vs Pressure

Our Altitude vs Pressure graph is really strange.  It should be a smooth curve as the pressure approaches zero, but it starts to go really weird at about 11:51am.  It could be a problem with the TP sensor. We may have to try a different sensor for any subsequent launch.

Our GoPro data had some issues too: When we look at the GoPro footage, one camera lasted only 34 minutes and 53 seconds (11:46:53 MT), and the other camera last only 30 minutes 10 seconds.  We had fully charged the batteries in both, but after looking at the data both stopped at our coldest point.  In addition, we had a mechanical failure of some sort, likely due to the impact of an additional spot that we had rigged above the launcher that collided with one of the GoPro’s at 32:09 (11:44:09 MT) into launch.


One of the first lessons we ever learned from the Loki Lego Launcher is to not speculate, and rely on data. We have learned a lot from the data on this launch. Some of it, we don’t understand (the Temperature/Pressure sensor).  Some of it tells us that we didn’t fully check out our wiring (no solar panel data).

Other data confirms that we were able to see the shadow of the moon (visual GoPro data), yay! It also confirms we had a mechanical problem at 32 minutes into launch and our camera batteries don’t work in cold temperatures. However, the good news here is that we were delayed in our launch by almost half an hour. We had originally planned on launching around 10:45am, and we didn’t get the balloon off until 11:12am. Because of that, we were able to get at least a few images of the shadow of the eclipse moving across the earth, hurray!

There are many lessons that we learned, and we are continuing to talk about them as we continue our long drive home (our car ride home always seems to be our mission debrief session).  Stay tuned for more lessons learned, and more thoughts on how awesome it is to be part of a scientific team!




Eclipse Launch Day: play by play

We are going to try to keep this blog post updated throughout the day today. We have limited internet access and limited power where we are, so that may be a challenge.

Here are two links that hopefully can track the Loki Lego Launcher 3.0 when it launches.

The forecast for today is for clear skies, but strong winds, which could be problematic for a balloon launch. For a live stream of the eclipse, go here: https://www.nasa.gov/eclipse2017


9:05pm. We have arrived back at the ranch. We’re tired and exhausted from the 2.5 hour hike through cow fields to retrieve our launcher, but we’re so happy. Not only was the eclipse super awesome, and we were able to successfully recover our spacecraft, but we feel like we belong to the team. The people from the Montana Space Grant have welcomed us from the moment we got here, helped us with everything to do with our launch, and were excited with us after our mission. We’ve learned so much this weekend, and being part of a group of scientists and engineers feels really good. We’re so happy!

6:21pm. Launcher RECOVERED! Had to navigate through several cows, but they got it!  A little concerned about our data though, it looks like a wire on the solar panel came loose. We’ll see after we get a chance to review our data. Right now, we have to hike back to the car before it gets dark!

5:57pm. Walking. Walking. And walking. Looks like we’re getting closer.

5:35pm. We are walking in the middle of nowhere trying to retrieve the launcher. Literally the middle of nowhere.

1:08pm. We have landed! It looks like the launcher is on the ground, about an hour and a half drive into Nebraska. We are coordinating recovery operations now.

12:34pm. It looks like our launcher went into Nebraska, but it has now burst and is coming back down, and seems to be coming back into Wyoming!

12:13pm. It seems like there was someone else on our APRS frequency, but we’ve just re-acquired our signal. So far, the launcher is heading in the direction we expected. With luck, we will have captured an image of the moon’s shadow. We won’t start recovery efforts until later.

11:53am We just witnessed totality! What an amazing experience. We’re so grateful to be here with all these incredible people supporting us with the launch and witnessing the eclipse together.

11:17am We have launched! Loki Lego Launcher 3.0 is off! Tracking enabled. Fly, Loki, fly!

11:01am Adding astrobiology microbe experiment.

10:48am balloon fill.

10:36am. First contact! The moon is starting to cover the sun. LLL 3.0 is ready to go.

10:15am. Making adjustments to APRS. Powering on flight computer and GPS units. Anticipate balloon fill in about 20 minutes. Confirming payload weight.

9:16pm. Watching the pros prepare for launch. This beast is a 5000g balloon that will be carrying a six camera 360 degree rig. The girls will be launching a 2000g balloon today. Their previous launches have used 600g and 350g balloons.

7:53am. Everyone up, having breakfast. Definite buzz in the air. Watching the Sent Into Space team start preparing their custom rig; they will be launching first on an enormous balloon. Many folks concerned with the wind.

6:11am – Dad here. Kids are still sleeping, but breakfast is being served for all eclipse ballooning teams. Need to get them up.

Tomorrow’s the Big Day!

It has been a long, hot day at the Fort Laramie Bed and Breakfast, where we have been testing and making final pre-launch decisions.

Yesterday we drove seven hours from Jackson to Fort Laramie, with a stop in Casper to say hi to our friend from Blue Origin, Heather Nelson.  When we got to Fort Laramie, we met up with the BBC film crew and headed to the makeshift campground next to the B&B.

This morning we had a very interesting conversation with Jen Fowler, Assistant Director, Montana Space Grant, and also our Launch Director.  Instead of an Iridium satellite tracker, we will be using a second SPOT tracker as a redundant tracking system.  Ms. Fowler also talked to us about lift calculations, the NASA microbe experiment, and the data from our previous launches. We also talked to Dr. June Wang, an atmospheric scientist from SUNY, who talked to us about the science behind the data we came up with, calibrating our instruments, and waves in the stratosphere.

We also got to watch one of the teams launch a radiosonde, which was really cool because we got to see how their teams did it, how they filled their balloon, how they released their payload, and how they received data. It looks like it was helpful to have a lot of hands helping! We learned so much.

We spent a lot of time testing our flight computer, APRS tracker, SPOT Trace tracker, and GoPros.  Ms. Fowler helped us with our APRS by lending us a portable ham radio, which is really interesting to use because we’ve never used one before. We had a problem with Internet access, so the radio was really helpful.

But the biggest problem we found was that one of the wires connected to the solar panel came out of the port, causing the flight computer to not work. We’re lucky we tested today and not tomorrow!

Tomorrow we’re going to launch and we’re super excited!  All of our hard work on this project is finally going to come together in a spectacular launch. We hope…. We’re really grateful for the opportunity to learn from and launch with some amazing scientists, balloonists, and engineers from all over the country on this Eclipse Ballooning Project. We wish you all clear skies!

Only Two Days Until the Eclipse!

We are heading to the launch site today in Fort Laramie, WY. We may not have great Internet service or any service at all around our launch site. Just in case we can’t update anything, here is our APRS link to follow the Loki Lego Launcher 3.0 on Eclipse Day.


We will also have our SPOT Trace GPS tracker going, which can be followed here:


We plan on launching around 10:45 am MT on Monday, August 21. We won’t start recovery operations until after 3pm MT. Right now, our current predictor has our launcher landing in Western Nebraska. We hope it doesn’t land in a corn field, because that would make it really hard to find! For a live feed of a MSGC balloon, also check out http://eclipse.montana.edu

We have had a lot of media coverage the last few days, and we’re very grateful for the recognition. Thank you to Good Morning America for having us on the show, and for asking us to demonstrate the eclipse the next day. Thank you to World News Tonight for choosing us as Persons of the Week. We wish we could have made the opportunities with CTV and Channel NewsAsia work out. We are look forward to working with the BBC on a documentary in Fort Laramie, but that’s all we can talk about for now.

But now we’re focussing on the preparation for the launch; there is so much to do! We need to figure out how to add an Iridium tracker to our Loki Lego Launcher, and then weigh our payload to calculate how much helium we’ll need in our 2000g balloon. We’re excited to meet the other eclipse balloon teams, and the scientists from University of Montana, MIT, SUNY, and more. In addition, we need to figure out how to stay cool for the next three days, because it’s going to be in the 90’s and we’ll be camping in an open field with no shade!

Our Eclipse Diorama

We recently made a made a diorama (3D model) of the Loki Lego Launcher and the solar eclipse at Tech Tales, a program run by the University of Washington, Seattle Public Libraries, and the Pacific Science Center.

Using Scratch, a block programming language, we made the styrofoam moon orbit the Earth on a rotary motor. A light sensor embedded in the Earth checked if the flashlight/sun’s light was blocked by the moon, meaning a solar eclipse occurred, triggered two elements. One was a multicolored LED that changed from red to green signifying an eclipse, and another motor that moved in a semicircle, showing our launcher launching and landing. We learned to program in Scratch in school, so we knew what to do when we needed to make the programs.

We also had a little paper car stuck to a stick, which we connected to a rotary motor. In this way it would look like the car was driving around in a circle. The car was connected to a dial, and when we turned the dial, we could change the speed of the car. The point of having this is to show our road trip by having a map of Yellowstone National Park, and the car driving around it.

A few of the challenges we had in this project included figuring out how to connect the Hummingbird Duo (a type of Arduino computer board) to the computer, because the program has to go through something called the BirdBrain Robot Server, and that kept dropping the connection. Also, it was challenging figuring out how to mount our computer board to our diorama.

It was a lot of fun to make!


T-Minus Six Days and Counting!

We can’t believe it’s only six days left until the eclipse! We’re super excited about the upcoming launch. But we’re also a bit nervous too, because there are so many things to do and we are getting lots of communications from the Montana Space Grant. It’s so cool to be part of a bigger project with real scientists, but we hope we don’t mess anything up!

We’ve had no internet access for the last few days because our family has been on a trip to Yellowstone National Park. We saw lots of wildlife, including bears, wolves, bison and elk, and we saw geysers, hot springs, and mud pots too. There was a lot to learn about biology and geology!

But now it’s about astronomy and engineering and technology as we prepare for the launch. Being part of the Montana Space Grant Consortium (MSGC), we now have a detailed schedule of the days before launch and launch day itself. The MSGC group with the Wyoming site eclipse ballooning team is split into two groups: the Radiosonde group and the Large Balloon group, which is what we belong to.  Under the National Space Grant program eclipse ballooning activities, we are all covered by a national NOTAM (Notice to Airmen) issued by the FAA. This is all official!

We are one of five large balloons that will launch on Eclipse Day: Four Science balloons (Sent into Space, Loki Lego Launcher, MSGC Science Payload, and MIT LL payloads) and one MSGC Live Video payload.  This will be the one that will be broadcasting images live to a ground tracking system, which will then be available for everyone to see online.  We will not be broadcasting video live from the Loki Lego Launcher, but we will be providing our APRS tracking data in almost real-time, like our last launch.

Here is our planned schedule for the days leading up to the eclipse:

Aug 18 – MSGC teams make their way to Fort Laramie, WY

Aug 19 – Teams do site survey, full systems test

Aug 20 – Radiosonde teams do initial launches, large balloon teams do full systems test

Aug 21 – Eclipse Day (all times Mountain Time):

10:00am Large balloon prep
10:25am Start to inflate the large balloons
10:45am-11:00am Large balloon launches!  Will be separated 1-2 minutes apart to avoid tangling lines.
11:15am Large Balloon Launch (MSGC live video payload)
3:00pm-7:00pm Payload retrieval.
Post Launch: Eclipse, Science, Nerd party! (borrowed from our site schedule)

None of this would be possible for us without all the people at the Montana Space Grant Consortium.  Thank you for this amazing opportunity!



Saved by SPOT!

Something that’s been on our mind recently is the fact that we couldn’t find our SPOT Trace GPS tracker. We moved recently and the SPOT is somewhere in a moving box. We’re leaving for the trip soon and we were super worried because we need the SPOT to weigh and make all our final calculations.

Just yesterday, a package arrived addressed to Rebecca and Kimberly Yeung! We were surprised because we usually don’t get packages. When we opened it, we saw the package for a brand new SPOT Trace! We also found a very nice note from the people who work at the SPOT and GlobalStar company. We’re super grateful that we can launch with a SPOT GPS again and we can now make all our complete weight calculations. Thank you SPOT!


Two Weeks Until the Eclipse!

There are only two weeks left until the eclipse, and we have been busy preparing for the upcoming launch. We’ve done several tests, ran a number of calculations, and done research on the eclipse.

This launch is going to be much more challenging than our previous launches. The shadow of the solar eclipse is moving across the surface of the earth at over 1600mph (2500 km/h), which gives us a time window of approximately two minutes and forty seconds. This means we have to time our launch so that our launcher is at the right altitude and location when it enters totality.


We want our launcher to be at roughly 80,000 feet when it hits totality. If it is too low, we won’t be able to capture the blackness of space with the shadow of the moon and the curvature of the earth. If it is too high, we risk the balloon bursting before the launcher can film totality.

The lift of our launcher is affected by the lifting force of our balloon and the weight of the payload. The University of Montana is generously providing us with a 2000g balloon and the helium, which will give us more lift than our previous two launches. Because of our additional lift, we’re able to to include more weight on our payload than previous launches. We’ll be able to include an additional GoPro as well as an Iridium satellite tracker (more on this later).

Calculating our ascent rate is complicated due to these changes in lift and the weight of our payload. This is further complicated by the fact that we want to hit 80,000 in a 2 1/2 minute window of time.


The width of the shadow of the moon on the earth in totality is approximately seventy miles. Since we will be launching from near the center of the path, that means we have about 35 miles of leeway in a north-south direction. We have no way to predict the wind two weeks in advance, but wind directions a week from now indicate wind is blowing in a east-west direction. In previous missions, our launcher travelled approximately 50 and 70 miles from launch to landing. So, we have the added complication of trying to launch in the correct location so that our launcher stays within the path of totality.

So this is why our calculations this time are much more complicated than previous launches.


We have been offered an Iridium satellite tracker which communicates through a network of Iridium satellites in orbit around the world. This provides us with an additional redundancy in tracking and retrieval in addition to our SPOT GPS tracker and our APRS Radio Bug. Thank you Montana Space Grant for offering this to us!

We have recently been featured in some media, and we’d like to give our thanks to the Seattle Times, GeekWire, and Q13 News.

For the first time, our project isn’t just our family alone, but we’re now part of something bigger. We’re very grateful to be part of the Eclipse Ballooning Project, and are looking forward to sending our data to NASA. It’s thrilling to be working with real scientists from different educational organizations around the country. We’ve been e-mailing with people that we’re soon going to be working with, and every time we receive a new e-mail it feels very humbling.

We’re really looking forward to this launch!