Look: UAE's Hope Probe discovers huge 'worm-like' aurora on Red Planet

The UAE’s Hope Probe has captured stunning images of a mysterious Martian aurora that the world has never seen before. It appears as a huge ‘worm-like’ aurora that extends halfway around the Red Planet.

The Emirates Mars Mission (EMM) on Wednesday released images of the discovery dubbed ‘sinuous discrete aurora’. The finding not only provides new information but also leads to new questions about the interactions between the planet’s atmosphere, its magnetic fields and the solar wind.

“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 EMM 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 energised electron emission in the upper atmosphere. It’s thousands of kilometres long and stretches from the dayside to the nightside of Mars.

It was captured during a solar storm on the planet, 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.

EMM project director Omran Sharaf said having additional bandwidth and resources allowed the team to dig deeper into Mars’ discrete auroras.

“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,” he said.

Hope’s new observations include ‘draped’ magnetic field lines, which don’t touch the nightside atmosphere; ‘closed’ field lines, which connect to the crust at both ends; and ‘open’ field lines, which connect the crust to the solar wind.

These ‘open’ field lines funnel electrons toward the atmosphere in sometimes intricate patterns, which are then reflected in the resulting UV emission detected by the orbiter’s Emirates Mars Ultraviolet Spectrometer (EMUS). As they are spatially confined, these emissions are known as “discrete auroras”.

The sinuous discrete aurora was a ‘shocking discovery’, said Dr Rob Lillis, EMUS team member at the University of California, Berkeley.

“In many ways, it had us scratching our heads and going back to the drawing board. We have ideas but no solid explanation for why we are observing intense aurora of this shape and at planetary scales. We now have the opportunity to re-examine prior observations of Mars by missions such as MAVEN and Mars Express to search for signatures that could flesh out Hope’s new observations and perhaps help us try and unpick what is happening here,” Lillis said.

What makes Hope’s Martian aurora discoveries unique

Three types of auroras have previously been observed around Mars: the diffuse aurora, the discrete aurora and the proton aurora.

While these had been identified, no clear global images of the discrete aurora were available — until the EMM’s Hope Probe started studying the planet.

Now, an increased focus on discrete aurora observations by the EMM science team has resulted in observations of this new phenomenon of sinuous discrete aurora.

“Since those first observations of the discrete aurora, we continued to see incredible new patterns that open new insights into the interactions of charged particles in the Martian atmosphere,” said EMM lead Hessa Al Matroushi. “There is a very great deal of new information here for the EMM science team to unpick.”

nandini@khaleejtimes.com

• UAE