NASA’s MAVEN observes Mars light show caused by major solar storm

For the primary time in its eight years orbiting Mars, NASA’s MAVEN mission witnessed two various kinds of ultraviolet aurorae concurrently, the results of solar storms that started on Aug. 27.

MAVEN—the Mars Environment and Unstable Evolution mission—is the one asset at Mars in a position to observe the sun’s exercise and the response of the skinny Martian atmosphere on the identical time. Actual-time evaluation and simulations of the solar eruptions from NASA’s Moon to Mars Area Climate Evaluation Workplace additionally allowed the MAVEN group to appropriately predict when the growing solar storm would attain the Purple Planet.

Correct space climate forecasting is important to assist defend present missions and future human explorers on the Purple Planet as a result of not like Earth, Mars lacks a world magnetic discipline to defend in opposition to the damaging radiation solar storms can convey.

It began with the sun

On Aug. 27, an energetic area on the sun produced a sequence of solar flares, that are intense bursts of radiation. The flare exercise was accompanied by a coronal mass ejection (CME), a large explosion of fuel and magnetic power that leaves the sun and propagates via space. This interplanetary CME impacted Mars a number of days later.

This CME produced one of many brightest solar energetic particle (SEP) occasions that the MAVEN spacecraft has ever noticed. The SEPs that had been accelerated forward of the CME had been noticed at Mars by MAVEN’s SEP detector on Aug. 27. In actual fact, a lot of MAVEN’s devices had been collectively in a position to measure the energy of the solar storm, together with the Excessive Ultraviolet Monitor, the Magnetometer, the Photo voltaic Wind Ion Analyzer, and the Photo voltaic Wind Electron Analyzer.

“By using space climate fashions of CME propagation, we decided when the construction would arrive and impression Mars,” stated Christina Lee, a space physicist on the College of California, Berkeley, who’s a member of the MAVEN mission group and is collaborating with the Moon to Mars Area Climate Evaluation Workplace scientists. “This allowed the MAVEN group to anticipate some thrilling disturbances in Mars’ environment from the impacts of the interplanetary CME and the related SEPs.”

Catching the Martian gentle present

Particles unleashed by the solar storm bombarded Mars’ environment, inflicting brilliant auroras at ultraviolet wavelengths. MAVEN’s Imaging Ultraviolet Spectrograph (IUVS) instrument noticed two varieties: diffuse aurora and proton aurora.

A part of the rationale that this unbelievable duo was noticed concurrently got here right down to timing. Mars is on the finish of dust storm season, which happens each Mars 12 months throughout its closest strategy of the sun. These dust storms heat the environment sufficient to permit water vapor to succeed in excessive altitudes, the place it’s damaged up by solar ultraviolet radiation, releasing hydrogen atoms within the course of.

When the incoming solar wind hits all this further hydrogen, the dayside of the planet lights up with ultraviolet emissions. These “proton aurora” simply occurred to coincide with the arrival of much more dynamic energic particles that penetrated deeper into the environment, creating diffuse aurora seen throughout the complete nightside.

Sumedha Gupta, a postdoctoral researcher with the IUVS group on the Laboratory for Atmospheric and Area Physics on the College of Colorado Boulder, first seen the coincidence throughout her routine test of incoming information a number of days after the occasion. “I used to be so stunned to see proton aurora concurrently diffuse aurora, as a result of it had by no means occurred earlier than,” she stated. “They’re each growing with solar activity, so we hope it retains taking place!”

An indication of the storms to return

This gentle present is an indication of issues to return for Mars and for the MAVEN group. The sun is rising increasingly energetic with occasions, similar to flares and CMEs, because it approaches solar most in 2024–2025. Photo voltaic most is when the peak of solar exercise peaks within the sun’s 11-year solar cycle, which means CMEs and SEPs are anticipated to extend in frequency and proceed to impression Mars’ environment.

“It is thrilling to nonetheless be observing ‘firsts’ like these simultaneous aurora so a few years into the mission. We have now a lot to study in regards to the environment and the way solar storms have an effect on the Purple Planet,” stated Shannon Curry, MAVEN’s principal investigator on the College of California, Berkeley. “Our group can’t anticipate the following few years of observing probably the most excessive circumstances throughout the MAVEN mission’s lifetime.”