Last days on the Ice

Four of the last five of the SPIDER crew– Don, Ed, Sasha, and I– are slated to leave the Ice tomorrow morning. That means this is probably my last blog post– at least until SPIDER 2! It has been an incredible few months, but I can’t say I’m all that sad for it to be ending. I’m ready to have an adventure in New Zealand and then get home to all the people I’ve missed so much while I’ve been away.

As is the nature of field campaigns, it has been an absolute roller coaster, but the highs have certainly made the lows fade in my memory. We got SPIDER on that balloon, and despite all of the complexities and possible points of failure, it worked. That’s a high I won’t be coming down from any time soon.

On top of success with our experiment, we’ve also had the privilege of exploring this amazing part of the world. Many would sacrifice a great deal to get to see this place, and we come here simply as a means to an end. I’ve tried to take advantage and soak it in as much as possible, and I hope I’ve illustrated the experience well enough to bring you all along for the adventure in a small way.

This past week, I’ve gone on all of the hiking trails available in McMurdo, and I’ll close this blog with the pictures from those adventures. Thanks for reading and for all of your support!

The end of SPIDER’s flight

SPIDER was released from her balloon at 5:55 am local time today (11:55 EST Saturday), and parachuted gracefully (we think) to earth. She took a pretty weird tour of the continent. The winds didn’t act exactly as we expected, and we went very slowly along for most of the time. Since our cryogens ran out yesterday afternoon, and the winds would have only pushed us further north, we cut her down. SPIDER’s final landing place is near several small sites, as close as 70 km away, which might be used for recovery of the data drives and other small parts.

John Ruhl made cool trajectory maps. This one shows just about our final flight path, made a few hours before we landed. We'll recover SPIDER using planes taking off from ITASE-1.

John Ruhl made cool trajectory maps. This one shows our whole flight path and final resting place. We expect to recover SPIDER using planes taking off from ITASE-1.

With recovery the last remaining piece of the campaign, much of the crew headed north yesterday. Only six of us remain, and we will all be glad to no longer be on shifts watching for our little data packets. Hopefully we can get a quick recovery done and head north ourselves, but we’re not sure when that will be yet.

I went on one adventure this week, and that was to go out to Hut Point to watch the ice breaker on its way in. It is clearing the way for the big cargo vessel that will arrive this week and supply McMurdo with 18 months worth of food and supplies. Steve and I went out hoping to see some awesome ice crushing action, but the boat was too far away to really see do its thing. Instead, we were treated to a bunch of seals swimming by. Seals look like way more majestic animals in the water than they do on the ice. It was fun to watch them swim and play with each other in the crystal clear water.

Every Thursday night at Scott Base, they have America night, which is the only time Americans are allowed in their bar (I mentioned this in a previous blog post- the only other time I’ve gone to America night). On Friday morning as a special treat, they opened up Scott Base for Day Bar America Night. So night shift people could enjoy as well! Since there is usually very little social life for night shifters, this was a pleasant break from the usual routine.

Outside Scott Base, there is a veritable swarm of seals, so I took a couple pictures of them.

Now we get a day or two of absolutely nothing to do on SPIDER while logistics of recovery are worked out. Hopefully we’ll have nice weather and I can get out and find something more exciting to document!


SPIDER has now been at float for a little over a week. The payload has been very slowly wandering south, a different trajectory than you’d usually expect for an LDB. Normally they make circular trips around the continent, but SPIDER is doing her own thing, wandering in an approximately straight line.

SPIDER's flight path so far after a week.

SPIDER’s flight path so far after a week.

While SPIDER was in our line of sight, we could communicate with the payload with high bandwidth- it was almost no different than commanding and data streaming on the ground. For those first couple of days, we got to make tweaks and get fast feedback and got all the systems in nominal working configuration. The change to over the horizon telemetry was stark. Now, our standard operating mode is through an Iridium link. This link provides us with a packet approximately the size of a text message every 15 minutes, providing us with a few snippets of temperature data, pointing information, and system states that inform us only about gross health of the system. We can also command through this link, although commands can take up to a minute or two to get to the payload, and then you have to wait up to 15 minutes to get a new packet to confirm that your command went through.

I was very nervous before flight about this limited information, but it has in fact been quite sufficient. SPIDER is boring. It is just working. It’s a great position to be in, especially since there are remarkably few knobs you can tweak to fix anything now that it’s up there!

Once a day, during our helium-3 fridge cycle, we get to turn on our high bandwidth antenna and get data streams and fast commanding. We only turn this link on during fridge cycles because our detectors are very sensitive to it and so take no useful data while it is on. We can get about 20 minutes of compressed old detector data for about 80 detectors (out of ~2000) during this high bandwidth period, which means that we get to spend the whole next day obsessing over this tiny data set and seeing what we can learn from it.

And let me tell you, analyzing real CMB data is awesome. We have a running joke in SPIDER about what qualifies as “science”. There is a lot of experimental physics that very much does not feel like science, but a lot more like grunt work or art and crafts. Without a doubt, we are now definitely doing science, and it is the coolest thing I’ve ever done. Can’t wait to have all that data at my finger tips once we get our hard drives back!

These days we are monitoring the payload from an office in town, and going out to LDB to pack up the lab when there is time. So I don’t have a lot of pictures. I’ve posted below the few I’ve taken since launch, and also courtesy of Steve, my last photo with SPIDER.

SPIDER and me on hang test day.

SPIDER and me on hang test day.


This is surreal.

I have been working on SPIDER for three and a half years, and much of the rest of the collaboration has been working for many years beyond that. We have all gone through intense times of stress and disappointment, victories and defeats. The personal sacrifice on the part of every individual on the team to get SPIDER to the point of flight readiness has been a weight on all of our shoulders as we prepared to launch our hopes and dreams on a balloon.

Ballooning is incredibly risky. Everything can work flawlessly on the ground, and then one thing can break during launch, or freeze or overheat at float altitude, and no amount of commanding from afar can bring it back to life. This happens so often in ballooning, and all you can do is obsess over every aspect of the experiment, have redundancy where possible, and hope that there is nothing that you have missed. Luck helps too.

We can happily report that so far as we can tell, everything is working fantastically. We had a couple of bugs to sort out, but had the necessary redundancy and planning to deal with the problems that arose. None of our major fears came to pass, and we are now taking some state of the art pictures of the CMB. I am so proud of this team and what we have accomplished. I work with a remarkable group of people- a dedicated, hardworking, and brilliant team that I am also privileged to call friends. We have had high highs and low lows. We have had a grueling integration campaign in Texas, a government shutdown delay our launch by a year, a host of cryo-tastrophes, shipping damage, broken components, and weather delays upon weather delays. But we have worked diligently toward this single goal, and now that we have met it, I couldn’t be more proud.

Ok, now that I have indulged in sentimentality, let me tell you about launch day. Since time of day means absolutely nothing here, I will define launch day as starting at 4:30 am Dec. 31, since that is the last time I was asleep before we launched. This was hang test day. Before you launch, you have to go through the motions of getting ready to launch. The launch vehicle comes and picks up SPIDER and takes her out, but then stops before going to the pad. We make sure all our systems are functioning and all of our telemetry links are operational, and then come back inside. This is also a great opportunity for pictures!

We rolled out a bit after 8, so everyone got in early that day to prepare. During the hang test, we were informed that weather for the next day would be good for a launch, which was absolutely thrilling to hear, but also meant we had a very long day ahead of us. Before launching, we needed to fill our helium tank to the brim, which takes several hours, and ensure that every last little thing was in working order and ready to fly. For me, this meant I didn’t sleep that night (though I did make an effort for a couple of hours). I was SO excited and terrified.

We rolled out around 4 am on New Years Day, and the weather seemed perfect. I was posted inside, monitoring the health of our cryostat and issuing commands for valving operations. As we got the all clear from the weatherman to roll out to the pad and lay out the flight train around 8 am, we were all giddy with anticipation. It was happening. We were ready. The weather was perfect.

But the weather wasn’t perfect. The winds higher up where the balloon would be during launch were too fast, and so we were put in a weather hold. This lasted for something like 5 hours, while we all kept monitoring systems, ready to launch whenever they would clear us. The adrenaline started fading, and I got tired, so I made a trip out to the pad to get excited and woken up again. Shortly after I returned inside, we got the word that the winds had settled, and we were launching.

I planted myself in front of my cryo plots, and nervously watched, willing everything to stay ok for one more hour as the balloon inflated. I made a quick sprint outside to see the beginning of balloon inflation, and after sending my final valving commands minutes before launch, I ran outside again to watch the balloon take SPIDER away. I was a mess of nervous energy, along with most of the rest of the team. As soon as we were off the ground, I raced back inside to check on systems. I radioed the team, gleefully informing them that cryo looked fine, that everything looked fine. We had survived launch.

Over the next couple of hours, we all huddled around our computers, and as each subsystem came online, working as designed, we all cheered. By 9 PM, we were at float altitude and nothing had gone seriously wrong. I went home and slept like a rock as others got all of the details sorted and started taking data on the CMB.

Now we’re on shifts monitoring the tiny packet of data we receive every 10-15 minutes telling us that everything is ok up there. And everything is ok up there. Just like we designed it.