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When the sun unleashed an extreme solar storm and slammed into Mars in May, it engulfed the red planet in auroras and a stream of charged particles and radiation, according to NASA.
The Sun has been exhibiting more activity over the past year as it approaches the peak of its 11-year cycle, called a solar maximum, which is predicted to occur later this year.
Recent months have seen an increase in solar activity, including class X explosions, the most powerful solar flares, and coronal mass ejections, or large clouds of ionized gas called plasma and magnetic fields erupting from the sun’s outer atmosphere.
Solar storms that reached Earth in May sparked colorful auroras dancing across the skies in rarely seen regions such as Northern California and Alabama.
The storms were caused by a massive cluster of sunspots facing the Earth. Later, this sunspot cluster rotated in the direction of Earth’s cosmic neighbor Mars.
Astronomers used multiple orbiters orbiting the red planet, as well as rovers orbiting its surface, to capture firsthand the effects of a solar storm on Mars and better understand what kind of radiation levels the first astronauts on the red planet might have experienced. in the future.
Solar radiation hits Mars
The strongest storm occurred on May 20 after an X12 flare emitted from the sun, according to data collected by the Solar Orbiter spacecraft, which is currently studying the sun.
The massive flare blasted X-rays and gamma rays towards Mars, and a coronal mass ejection quickly released after the flare blasted charged particles towards the red planet.
X-rays and gamma rays traveled at the speed of light to reach Mars, followed by charged particles for tens of minutes, according to scientists who track activity from NASA’s Moon to the Mars Space Weather Analysis Office at Goddard Space Flight Center. reached within. Greenbelt, Maryland.
The Curiosity rover, which is currently exploring Gale Crater just south of the Martian equator, used its navigation cameras to capture black-and-white images during the solar storm. According to NASA, the snow-like white streaks visible in the images are a result of charged particles hitting Curiosity’s cameras.
The energy from the solar particles was so strong that the star camera on the Mars Odyssey orbiter, which helps determine the probe’s orientation as it orbits the planet, momentarily shut down. Fortunately, the spacecraft was able to turn the camera back on within an hour. Odyssey last encountered such extreme solar behavior during solar maximum in 2003; An X45 flare had fried the orbiter’s radiation detector.
Meanwhile, Curiosity used its Radiation Assessment Detector (RAD) to measure the amount of radiation hitting the planet during the storm. An astronaut standing next to the rover would be exposed to radiation equivalent to 30 chest X-rays; It wasn’t fatal, but it was the largest wave of radiation the rover’s instrument had measured since landing nearly 12 years ago.
Understanding the maximum amount of radiation astronauts might encounter on the red planet helps scientists plan how to protect future crewed exploration of Mars.
“Cliff edges or lava tubes would provide additional protection for an astronaut against such an event,” said Don Hassler, RAD principal investigator in the Solar System Science and Exploration Division of the Southwest Research Institute in Boulder, Colorado, where the dose rate would be significantly higher in Mars orbit or deep space. “I wouldn’t be surprised if this active region on the Sun continues to erupt, meaning more solar storms on both Earth and Mars in the coming weeks,” he said.
Auroras on the red planet
The MAVEN orbiter, which stands for Mars Atmosphere and Volatile Evolution, had an aerial view of auroras dancing in ultraviolet light over Mars during a solar storm. The orbiter was launched to Mars in 2013 to study how the red planet loses its atmosphere over time and how space weather produced by the sun interacts with the upper Martian atmosphere.
But these auroras look very different from the northern lights, or aurora borealis, and the southern lights, or aurora australis, that occur on Earth.
When energetic particles from coronal mass ejections reach the Earth’s magnetic field, they interact with gases in the atmosphere, creating different colored lights in the sky, especially near the poles.
But Mars lost its magnetic field billions of years ago, meaning the planet has no shield against incoming energetic solar particles. So when particles hit Mars’ thin atmosphere, the reaction results in auroras that engulf the planet.
“Given that Mars has no global magnetic field, Mars’ auroras are not concentrated at the poles as on Earth, but instead appear as ‘globally diffuse aurora’ associated with Mars’ ancient, magnetized crust,” wrote Deborah Padgett. , Operational Product Production Subsystem mission leader at NASA’s Jet Propulsion Laboratory in Pasadena, California, on the space agency’s Curiosity rover blog.
According to NASA, future astronauts will one day be able to witness these light shows on Mars.
By tracking data from multiple Mars missions, scientists were able to track how the solar storm unfolded.
“This was the largest solar energetic particle event MAVEN has ever seen,” MAVEN Space Weather Lead Christina Lee of the University of California, Berkeley Space Sciences Laboratory, said in a statement. “There have been a lot of solar events in the past weeks, so we were seeing waves of particles hitting Mars.”
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