Keogramist: Explore 1400 Nights of Aurora on a Phone

Jeremy Kuzub (Jufa Intermedia), Dr. Elizabeth MacDonald (NASA Goddard Space Flight Center)

AGU Fall Session 2020

Author contact: jeremy@jufaintermedia.com

Abstract

The aurora research community has made full-colour all-sky camera (ASC) imagery available online for public outreach and education, providing a deep resource of archival material. Concurrently, modern mobile devices like smartphones have improved in capability, able to present interactive video and 3D content directly in web browsers. This work represents an example of citizen science in which an individual from another field repurposed, or "MacGyvered", existing AuroraMAX ASC timelapse archive, to make over 1400 nights of aurora activity more engaging and immersive for users of mobile devices. The resulting "Keogramist" web app is designed to be a visually intuitive gateway to explore and experience auroral activity. An "enhanced stacked keogram" interface organizes aurora activity temporally, and enhances visible features using minor image processing. Users can choose any night's keogram and replay and interact with the corresponding timelapse ASC video from a first-person perspective, emulating what a viewer would experience standing under the aurora and looking at the sky around them. Adjustable parameters can accommodate a range of existing ASC resolutions, fields of view, and replay rates, allowing other ASC archives to be explored in the same way. Scientific and public users alike may find the format beneficial as it provides quick, mobile review for events of interest. This platform may enable citizen scientists to interact with large amounts of data for image and feature characterization.

Motivation and Background

A 'Human' viewpoint of aurora video

An all-sky camera for automated monitoring of aurora. Although many cameras are designed specifically to gather calibrated, wavelength-filtered data, some are used as outreach and education tools, using standard consumer fish-eye lenses and digital SLRs imaging on Bayer-pattern RGB sensors. This public facing data is often compressed into lossy timelapse video, since specific calibrated measurements are not needed. (image from space.fmi.fi/MIRACLE/ASC/?page=stations)
All-sky camera timelapse video of aurora substorm[5] overhead in Yellowknife, NWT (AuroraMAX[6]). While projection like this is intriguing, it is not the same for a viewer as being in the presence of aurora and using their own senses (their field of view, sense of space, and ability to look around)
Inspiration: ASC camera data can be reprojected to make a more immersive experience, much like the approach taken by planetariums
Early proof-of-concept: what if we make a virtual online planetarium to make existing aurora ASC timelapses more immersive, using the same projection concept? This animation shows a viewpoint of walking into such a virtual space from the outside. The projected video can be seen on both inside and outside surface of the dome for debugging

An 'accessible' visual index of night sky activity: keograms

"Keograms"[1] stack the center column of consecutive ASC frame from left-to-right in an image, to give an overview of an entire night's sky activity at a glance, rather than parsing through hours of video
The relation of a keogram to the all-sky camera image and the time of night is intuitive enough to be understood with a little instruction
Citizen scientists and those interested in aurora have shown in a survey to readily understand keogram relationships to 'interesting' nights of aurora activity[9]

Implementation and performance

Keogram & metadata generation

Offline extraction of timecodes and keogram images directly from existing MP4 video was successful

Keogram index

A visually searchable HTML/Javascript index of 1400 nights of keograms and Kp data was performant on smartphones

AuroraDome viewer

Hardware-accelerated 3D rendering in browsers was suitable for real time re-projection of ASC video

What did we learn from a user survey?

Majority of surveyed users planned to use the app again. Users often ignore instructions, just want to start searching and experiencing. About 50% use smartphones.

User survey

Survey results from Alberta Aurora Chasers Facebook Group and Royal Astronomical Society of Canada (Ottawa) volunteers. Not reading the directions is a common issue in web-based interactives, so inline-familiarization is often preferable. Most respondents answered they would use the app again or share it.

Other findings

Researchers, citizen scientists, and enthusiasts used the app and provided useful feedback

Implications & next steps

This extensible platform can work for a variety of all-sky cameras and is a useful tool for amateur and professional audiences. Next steps include more cameras, more search filters, ability to tag specific events.

What is the most MacGyver aspect of this work?

This work puts existing all sky camera timelapse and realtime video archives in a whole new perspective. There is no need to go out and get new data, all we need is the existing timelapse video. The timestamp can even be extracted directly from the video frames in the absence of any other context. This application can bring citizen scientists and timelapse datasets into direct contact, and we have seen the success citizen scientists have had in broadening aurora research.

References

[1] Plasma Injection at Synchronous Orbit and Spatial and Temporal Auroral Morphology R. H. Eather, S. B. Mende, R. J. R. Judge

[2] Mobile vs. Desktop Usage in 2019, retrieved November 2, 2020

[3] Introduction to Progressive Web Apps, retrieved November 2, 2020

[4] Slicing the Aurora, Sebastian Lay et al.

[5] The Development of the Auroral Substorm" S.-I. Akasofu

[6] The AuroraMAX website

[7] Data portal at the University of Calgary Auroral Imaging Group data portal

[8] Conversation with Dr. Don Hampton, University of Alaska, Fairbanks, May 21, 2020

[9] Online survey directed to Alberta Aurora Chasers Facebook Group and Royal Astronomical Society of Canada (Ottawa Chapter) November 2020

[10] Aurorasaurus citizen science website

[11] WebGL Overview at khronos.org

Acknowledgements

Special thanks to

Dr. Eric Donovan, Dr. Emma Spanswick, and Darren Chaddock at the University of Calgary Auroral Imaging Group

Dr. Don Hampton at the University of Alaska, Fairbanks, Geophysical Institute

The Royal Astronomical Society of Canada (RASC) Ottawa Chapter

The Alberta Aurora Chasers Group

Laura Brandt of Aurorasaurus

Alan Dyer of RASC Calgary Chapter