The Emirates Mars Mission, recently released stunning new images of Mars’ enigmatic discrete auroras, following a new series of revolutionary observations that promise new answers – and new questions – about the interactions between Mars’ atmosphere, the planet’s magnetic fields and the solar wind. The observations include a never-before seen phenomenon, dubbed the ‘sinuous discrete aurora’ by the EMM team, a huge worm-like aurora that extends halfway around the planet.

“When we first imaged Mars’ discrete aurora shortly after the Hope probe’s arrival at Mars in 2021, we knew we had unveiled new potential to make observations never before possible on this scale, and we took the decision to increase our focus on these auroras.” said Emirates Mars Mission Science Lead, Hessa Al Matroushi. “We can obtain nearly whole-disk, synoptic snapshots of the atmosphere to investigate atmospheric phenomena and interactions. It means we are seeing discrete auroral effects on a massive scale and in ways we never anticipated.”

The sinuous discrete aurora consists of long worm-like streaks of energized electron emission in the upper atmosphere extending many thousands of kilometers, stretching from the dayside into the nightside of Mars. Imaged when Mars was experiencing the effect of a solar storm, resulting in a faster, more turbulent stream of solar wind electrons than usual, these aurora observations are some of the brightest and most extensive yet seen by Hope. They include elongated shapes, which may be caused by similarly elongated regions of electron energization conditions in the magnetotail.

The interplanetary magnetic field is carried by the solar wind and drapes around Mars, combining with magnetism in the Martian crust to form Mars’ magnetotail, a complex array of magnetic fields on the Martian nightside.

Omran Sharaf, EMM project director, said, “Having additional bandwidth and resources available to us meant we could be opportunistic and focus more on the area of discrete auroras than we had originally planned. That agility has certainly paid off as we have now opened up whole new avenues of investigation into these transient and dynamic phenomena. Novel science was a core mission objective and this is certainly novel.”

Observations made using Hope’s EMUS (The Emirates Mars Ultraviolet Spectrometer) instrument range between 90-180 nanometre wavelengths. Found at a wavelength of 130.4 nm, the UV emissions imaged in the new set of observations show where energetic electrons are smashing into atoms and molecules in the Martian upper atmosphere, some 130 km above the planetary surface.  These electrons come from the solar wind and are energized by electric fields in Mars’ magnetosphere.

Hope is following its planned 20,000 – 43,000 km elliptical science orbit, with an inclination to Mars of 25 degrees. The probe completes one orbit of the planet every 55 hours and captures a full planetary data sample every nine days throughout its two-year mission to map Mar’s atmospheric dynamics.

EMM and the Hope probe are the culmination of a knowledge transfer and development effort started in 2006, which has seen Emirati engineers working with partners around the world to develop the UAE’s spacecraft design, engineering and manufacturing capabilities. Hope is a fully autonomous spacecraft, carrying three instruments to measure Mars’ atmosphere. Weighing some 1,350 kg, and approximately the size of a small SUV, the spacecraft was designed and developed by MBRSC engineers working with academic partners, including LASP at the University of Colorado, Boulder; Arizona State University and the University of California, Berkeley.