aberti

The story behind creating and naming our favorite coyote.

Samuel Brieden, The University of Edinburgh

May 12, 2023

Welcome our new DESI ambassador for Education and Public Outreach (EPO), BaoBan! You might have met him already, when he was presenting our powerful focal plane (see a virtual tour through it here) or wishing a happy new year. From now on, BaoBan is assisting us with science communications, as long as he is in the mood. Although BaoBan is very attracted to the Mayall telescope, he shows up at Kitt Peak quite rarely because, like other wild coyotes, BaoBan spends most of his time hunting in the Arizona mountains. But whenever we are lucky enough to be honored with his visit, an aura of ancient wisdom about life and the night sky surrounding him sparks new insights and creative ideas. It’s a bit magical!

This article is a chronology of our common history with BaoBan. From the story of his ancestors, to how he was brought to life and given a name, and finally his meaning to us, to our roots as a scientific collaboration, and to our environment.

The Tohono O’odham Nation

DESI resides in the Mayall telescope at Kitt Peak National Observatory (KPNO), which sits atop I’oligam Du’ag (audio below) in the homeland of the Tohono O’odham (audio below) Nation (TON). Since time immemorial the Tohono O’odham (TO), meaning “desert people”, have lived in the Sonoran desert and preserved their rich culture. The nation is governed by the TON Tribal Government, organized into 11 districts. You can learn more about the history and culture of the TON here. We are deeply grateful for their permission to undertake observations of the night sky within the TON homeland at KPNO, and we cannot emphasize enough that the success of our scientific mission would not be possible without the TON’s generosity.

Pronunciation of “I’oligam Du’ag”

Pronunciation of “Tohono O’odham”

The DESI logo

It is this relation to the TON that must have inspired Berkeley Lab engineer (and artist!) Robin Lafever when he created the DESI logo in 2013, and in particular the detail in the lower right corner: the profile of a howling coyote. In fact, the coyote plays an important role in the TO mythology. Robin had seven different names for the coyote in mind, his favorite being “Bao Wao Wao”. “Bao” is reminiscent of baryon acoustic oscillations (BAO), the primary cosmological observable DESI is measuring to infer the expansion history of the universe, and “Wao” represents the coyote’s howl.

A new coyote is born

The DESI logo inspired Claire Lamman, PhD student at Harvard University and member of the DESI EPO committee, to transform Robin’s profile-view creation into a fully-fledged comic figure.  As you can see in her comic strips, at first the coyote seems nice and harmless, but the sheer power of the Dark Energy Spectroscopic Instrument occasionally evokes his dark side. All Claire’s comic strips can be found here.

Amazed by his strong character, the EPO committee considered how to introduce Claire’s extraordinary art to the public. There was only one thing missing for Claire’s comic figure to become even more successful than Looney Tunes legend Wile E. Coyote: a proper name!

Setting up a poll

Several candidates emerged from our initial brainstorming, playing either on the location of the telescope (Coyote-Kitt, Maya), on the pursued science (Cosmo-Coyote, Bao), or simply on the survey name itself (Desiree). This was so much fun that we decided to poll the entire collaboration for suggestions. Other names received were Can-do Canis, Desita, and the name of the original coyote in Robin’s DESI logo: Bao Wao Wao. Around 60 collaboration members voted in just one day, and the majority decided to conduct a naming contest within the Tohono O’odham school district (see the compilation of Slack messages below).

Back to the roots

We first consulted Jacelle Erin Ramon-Sauberan, PhD Candidate at the University of Arizona, faculty at Tohono O’odham Community College, and information specialist for AURA/NOIRLab, and worked closely with KPNO. Jacelle put us in contact with the TON Youth Council  (TONYC). The TONYC consists of four representatives from each of the 11 districts, and their mission is to enhance the cultural awareness and self-esteem of TON youth within modern times by organizing social events. The Council holds monthly meetings, which are open to the public. Francine Senechal, the TONYC Manager, kindly invited us to present the coyote naming contest at a Council meeting.

At the same time we decided to reach out to the TON, two collaboration members independently raised the idea that the name include “Ban”, the word for “coyote” in the TO language. It was suggested that we connect “Ban” with the TO word “Ba:”, meaning “Where”, such that the combination “Ba:Ban” is extendable to “Where is coyote looking?” This would allude to the mysteries of dark energy DESI is trying to unravel, and sparked the obvious idea of “BaoBan”, combining “Ba:Ban” with the previous suggestions that include “Bao”.

The day of the TONYC meeting arrived, and fortunately it was held virtually so I could attend from Barcelona. After introducing DESI and the science we pursue with it, I talked about our plan to find a name for the DESI coyote. I provided a list of all the suggestions we had collected so far, as well as their variants, meanings, pronunciations, etc., and asked them to vote for the name they found most suitable. The TONYC members were interested and very keen to help. They agreed to bring the list of names into the local youth communities of the district each of them represents, engage their members to discuss the different options, and choose their favorite name.

The final decision

After thoroughly considering all names, discussing them within each district, and exchanging their ideas at a meeting, the TONYC voted, and Francine communicated the official result:

1. BaoBan
2. Cosmo Coyote

What a great choice! Within the EPO committee we immediately fell in love with the name BaoBan, as it nicely combined all the different ideas the collaboration had in mind throughout the process. “Ban” as the TO word for coyote, reminding us of the roots of where the DESI telescope is built, and “Bao” as both the sound the coyote makes, and a clear reference to DESI’s primary science goal: measuring BAO from galaxy maps. These ideas culminated in another new comic strip by Claire (below), which celebrates that together with the TONYC we found such a beautiful name for our DESI ambassador! And there is even more to the story…

An alternative meaning

Not only did the TONYC vote for the name, they also put me in contact with TO language experts Leslie Luna and Ronald Geronimo from the TO Community College, with whom I discussed the prospect of connecting “BaoBan” to the meaning behind the similar suggestion “Ba: Ban”, where “Ba:” = “Where?” as mentioned before. As it turns out, the TO expression “Ba: ‘o …” actually means “Where is …”, but this does not imply that “Ba: ‘o Ban” would mean “Where is coyote”, because “‘o” is an auxiliary verb that must be accompanied by a full verb. However, we can extend the expression to “Ba: ‘o ñia g Ban” (audio below), which literally means “Where is coyote looking?” and argue that “BaoBan” (audio below) is just the short form of that longer name. In this way, the name BaoBan also serves as a symbol that we and the TON may work together to explore new discoveries in our beautiful sky.

Pronunciation of “Ba: ‘o ñia g Ban”

Pronunciation of “BaoBan”

Final remarks

Throughout this process it has been amazing to see how an enjoyable drawing and a simple idea (finding a name for that drawing) can lead to something big, both engaging the collaboration and establishing a new link between DESI scientists and the TO community.

BaoBan symbolizes how the enormous scientific effort by ~70 member institutions with over 700 active collaboration members from all over the world is deeply connected with the TO, who share part of their homeland to discover the mysteries of our universe. BaoBan reminds us that the night sky is the same for everyone, independent of national or cultural identity. Furthermore, BaoBan reminds us to always respect our roots and our environment, and to never forget that the deeper our maps of the cosmos become, the deeper the relationships we will foster among different cultures and people.

It is no coincidence that Robin Lafever began this processes at the very moment his pencil touched paper to create the DESI logo. Robin was known as a man with a wonderfully warm and engaging personality, who delighted everyone around him with his creativity. Almost two years after his passing he would surely be flattered that people enjoy his creation enough that they continue to develop it, from Bao Wao Wao to BaoBan.

Acknowledgements

I would like to express deep thanks to all the wonderful DESI collaborators involved in this journey, those who participated in the poll and brought in their naming suggestions, and especially Claire Lamman, Angela Berti, Biprateep Dey, Parker Fagrelius, and everyone from the DESI EPO committee. Special thanks also to Daniel Eisenstein, Dustin Lang, Eric Linder, David Sprayberry, Lori Allen, Arjun Dey, Nathalie Palanque-Delabroullie, Kyle Dawson, and Michael Levi. Finally, I am indebted to Jacelle Erin Ramon-Sauberan, Francine Senechal, Leslie Luna, and Ronald Geronimo for all their effort and kindness giving me insight into their fascinating culture.

Claire Lamman, Harvard University

April 7, 2023

DESI’s planetarium show, “5000 Eyes”, was recently released to the public. It will be shown in hundreds of planetariums around the world and translated into ten languages. The support and contributions of many DESI members grew this project far beyond the little film I initially imagined. Here is how “5000 Eyes” went from the daydream of a first-year graduate student to a global production.

A couple months after delivering my final show at Fiske Planetarium, I was sitting in a session at DESI’s 2019 summer collaboration meeting. I had committed to starting graduate school at Harvard in the fall but was undecided about a research path. I was new to cosmology and just starting to learn about DESI. When a talk started to go over my head, which was often, I imagined what a planetarium show about DESI might look like.

Kitt Peak was building an outreach center and I thought it would be nice to record myself giving a short planetarium talk about DESI that could be shown at the center. A leader from our Education and Public Outreach Committee, Parker Fagrelius, encouraged me to reach out to DESI’s director, Michael Levi, and seek funding from the DESI Institutional Board. With the enthusiastic support from Parker and Michael, I formulated a proposal to create a small planetarium film. My idea was to use as much existing media as possible—such as 3D models of the Mayall telescope, footage on Kitt Peak, and DESI data, to make the best use of any resources given to the project. It received unanimous support from the Institutional Board and I found myself, a graduate student still unsure about what my thesis would be on, in charge of a full-scale production.

Fortunately, I helped Fiske make a series of short films during my time as an undergrad at CU Boulder and generally knew what went into making a planetarium film. I developed a script based on the media available and what I knew of Fiske’s software. After many iterations on the script and feedback from DESI people, we began working with Fiske to produce the movie.

There is so much to say about DESI (just check out all the blog posts below this one!), so it was not easy to decide what to include in a 20 minute movie. One idea we wanted to make sure to communicate was that advances in modern cosmology don’t magically spring from the minds of a couple scientists. It takes many people, including many young people, with a variety of backgrounds. We came up with a selection of six DESI members from four continents. The international participants all found ways to get high-quality recordings themselves! For those of us in the U.S., we were able to coordinate an in-person shoot on Kitt Peak.

Our visit to Kitt Peak was my favorite part of making the film. We had two days with the videographer from Fiske to shoot interviews and capture footage of the telescope and mountain. During this time, the Kitt Peak Staff was especially helpful and accommodating. I was even able to carry out one of my support observing shifts in person. Up until this trip, I was hesitant about representing DESI as such a new member. But observing on the mountain made me feel like I was truly part of the collaboration for the first time.

As main production ramped up, I directed the Fiske team and coordinated some additional contributions of DESI members. In particular, once I found out that David Kirkby could make a moving 3D model of the focal plane, I knew we absolutely had to include it. Who doesn’t want to fly through a forest of robots?? He put in an impressive amount of work to faithfully bring the focal plane to life and create a memorable scene.

Fiske’s team was also very excited about the film, especially once we had the go-ahead to use galaxy positions from DESI’s full year one data. This was somewhat of a technical challenge, since they were determined to render every single galaxy and, unlike DESI, did not have access to a supercomputer! The resulting fly-through is stunning. All the time I spent using DESI data in my research did not compare to soaring through the most detailed map ever made of our nearby universe in a planetarium. I am very impressed with the work of Fiske’s production team.

Because DESI is an international collaboration, it was important to make the film widely available and in multiple languages. Many DESI members have volunteered to help create translations. As of the writing of this blog, there are plans to translate the film into 10 different languages! Small planetariums all over the world are excited to have access to a free film in their local language. The film’s download site also includes an educational guide and outreach package filled with additional material that DESI people have put together. Our science will reach a large, diverse audience thanks to the work of our collaboration!

It has been exciting to see the ways that DESI members are using this film to engage with their local communities. At the premieres, it’s also been a joy to see our family members, especially kids, get a glimpse into what we work on. Looking back, it’s a bit staggering to see how much this project has grown and how many people contributed. This truly is a film about DESI, by DESI!

As of the writing of this blog, the film has been downloaded by 112 planetariums in 31 states and 24 countries.

…in Story and Science

Joan Najita, NOIRLab

April 4, 2023

One of the most spectacular things in the night sky is the Milky Way, which arches above the 4-meter Mayall Telescope in this image. The DESI survey is currently underway at the Mayall Telescope at Kitt Peak National Observatory, which is located in the Schuk Toak District of the Tohono O’odham Nation. Known as “tohmog” or “to:mog” in the language of the Tohono O’odham, the Milky Way looks like a pale band of bright specks entangled with dark clouds and glowing red wisps that shimmer like fireworks. In one Tohono O’odham story, the Milky Way was created when Coyote, the trickster, was playing in the kitchen and looking for something to eat. Hearing someone coming, he grabs a bag of flour and escapes into the sky in a great hurry. The bag tears open and flour spills out, creating the Milky Way.

There’s an echo of that story in how astronomers understand the Milky Way, just with the light and dark reversed. Here the bright white specks are not powdery flour, but stars in our galaxy. And a different kind of powdery substance, interstellar dust, creates the dark clouds, by scattering and absorbing the light from background stars. This dust isn’t the same stuff we sweep up from under our beds. Instead, it’s a kind of “soot” that forms in the atmospheres of some stars and is the stuff from which planets like Earth are made. It’s pretty valuable stuff—just like the flour that Coyote ran off with!

In this image, we can also see other interesting features. The familiar constellation of Orion the hunter is just above the Mayall Telescope to the left. And the glowing red fireworks spread across the sky are bright clouds of gas in the galaxy that are lit up by hot stars.

Recovering from the Contreras Fire

Benjamin Weaver, NOIRLab

January 24, 2023

DESI collaborators have previously reported on the Contreras Fire and how it initially affected DESI operations along with an update as personnel were able to return to Kitt Peak National Observatory (KPNO). Even as we were cleaning up KPNO and the DESI instrument in August 2022, we knew that it would possibly be several months before the Tohono O’odham Utility Authority (TOUA) could replace the infrastructure bringing electrical power and line internet (a fiber-optic link) to KPNO. In fact, line internet was not restored until December 7, 2022, almost exactly six months after the start of the fire.

The story of restoring electrical power and the generators used while restoration was in progress is definitely worth telling, and far more lengthy and detailed than the story I’d like to tell now, recovering from the missing internet connection.

The DESI Data Management team, working closely with the on-site NOIRLab personnel, developed a plan to work around the missing internet, even as DESI returned to full-night operations. It wasn’t a new plan; in fact, it was a very old plan: “Sneakernet”. The idea is that a human being (presumably wearing sneakers) can hand-carry data on physical media from one location to another, and in certain circumstances, the effective bandwidth of that transfer can be much, much higher than the bandwidth of an internet connection or other communication channel. This is actually even more true now than it was in the past, because the storage density of physical media has experienced exponential growth similar to that of Moore’s law for CPU performance. However, while Moore’s law has been showing signs of reaching fundamental physical limits, storage density trends continue to rise.

With that in mind, we purchased six 2 TB SanDisk solid-state drives (SSDs), and a few fast USB cables. There is nothing exotic about the hardware; these items would be available in many consumer electronics or department stores. Then with the 6 disks initially carried to KPNO, we would place an entire night of data (or sometimes several nights) on a SSD. One of the personnel working at KPNO would be designated to carry the SSD to Tucson at the end of the work day. Then we would pick up the disk either in person or from a drop box and copy the data to NERSC where it could be processed with the usual DESI data pipeline. Since we purchased six SSDs, that meant we always had several SSDs on standby at KPNO in case an already-transferred SSD could not be brought back from Tucson to KPNO the next day. On weekends, no one would be available to carry the SSDs, so we simply had several nights on Monday evening’s SSD.  From the point of view of the pipeline, the only difference was that an entire night (or several nights) would arrive all at once, after a delay of 1 to 3 days, instead of the normal operations procedure of one exposure at a time, almost immediately after the exposure is completed.

The DESI instrument resumed taking data starting with night 20220825 (August 25, 2022). The first SSD was brought to Tucson on September 2, 2022. This process continued until line internet was restored on December 7, 2022. The original data transfer system was ready to go at that point and was reactivated almost immediately after line internet was restored. Thus the last night of data transferred by sneakernet was 20221206 (December 6, 2022). In total, 16,726 exposures over 100(!) nights were hand-carried to Tucson. This amounts to 6.1 TB of data.

The bandwidth of hand-carried SSDs is impressive, but so is the bandwidth of modern USB cables. After some experimentation, we discovered that we could transfer data directly from the external SSD to NERSC via Globus Online, with bandwidth performance indistinguishable from the case where the data were first copied to a workstation, then transferred via Globus. In other words, the limiting bandwidth was the internet itself between Tucson and NERSC, not the internal systems of the receiving workstation.

While we were transferring DESI data with a very old system (but with the latest SSDs), we were also experimenting with a new one: Starlink. In fact there were at least two separate Starlink installations active at KPNO during the recovery.  One, which we’ll call the “DESI Starlink”, was a strictly limited command and control channel for use by instrument experts. The DESI Starlink was not used for any significant data transfer. The other, which we’ll call the “NOIRLab Starlink” was used for more general access to all of KPNO. We did use the NOIRLab Starlink for some data transfer, with mixed results.

At least currently, Starlink works best with a point-to-point style networking connection, optimized for individuals or residences, much like a residential cable modem. Since the uplink bandwidth is currently a factor of 10-20 times slower than the downlink bandwidth, it is less practically suited as a two-way connection between two substantially-sized networks, such as between KPNO and the Tucson base facilities. This manifested as a significant, recurring routing problem. Although bandwidth was adequate for interactive use and for the transfer of small data files, the connection was frequently not working and the routing systems had to be monitored constantly. Nevertheless, we were able to use the NOIRLab Starlink to maintain an off-site copy of the DESI operations database. This copy would have been impractical to maintain using daily SSD transfers, because the copy is a real-time mirror of a live database; it is more of a stream than a set of files. There were occasions where the database mirror fell behind due to interruptions in the Starlink connection. In these cases files created by the database were transferred manually on the SSDs and then once in Tucson the data files were manually added to the database mirror.

It was interesting and a good experience to transfer data over sneakernet. It was also a lot of work and hours. I want to give credit to a big team who all contributed to this effort: Keith Blaine, Paul Demmer, Matthew Evatt, Steve Grandi, Bob Marshall, Rod Rutland, David Sprayberry, Christopher Stone, Bob Stupak (NOIRLab), Martin Landriau (LBNL), and Klaus Honscheid (OSU). Here’s one job we hope we never have to do again!

January 18, 2023

The all-sky camera on the Mayall telescope were the DESI instrument is located provides a view of the entire sky above Kitt Peak National Observatory. This camera helps observers monitor weather conditions and visibility, and confirm when it is safe to open the dome above the telescope. While the skies above Kitt Peak are very often clear, that is not always the case, as shown below in a series of camera images from the night of September 23, 2022. The night began with clouds and rain, and for over an hour flashes of lightning lit up both the sky and the camera view. Finally, toward the end of the night the storm gave way to thin clouds that allowed some stars to peek through. The final frame shows the Milky Way stretched across a mostly clear sky before the series starts over.

Credit: Luke Tyas

The all-sky camera can also capture celestial events, like the lunar eclipse that occurred on the night of November 8, 2022. DESI Lead Observer Luke Tyas created the timelapse below of the eclipse from 108 individual images from the all-sky camera. At first the full moon shines brightly just right of center, reflecting so much light into the sky that only a few bright stars are visible. As the eclipse begins the moon dims to a red dot scarcely brighter than the brightest stars, and the Milky Way can be seen following the eclipsed moon across the sky. As it nears the western horizon the moon emerges from the Earth’s eclipsing shadow, re-illuminating the telescope domes visible on the horizon and washing out the Milky Way.

Credit: Luke Tyas