Common Martian Mineral Jarosite Found in Ice Core Samples from Antarctica


International researchers were surprised to discover Jarosite, a rare mineral in mile-long ice cores from Antarctica. Incredibly, the find came by chance. While looking for minerals to understand ice age cycles, they found Jarosite.

Jarosite is a brittle, yellow-brown mineral. Occasionally, it’s found in mining waste and near volcanic vents. However, it’s generally found in places exposed to air and rain, not in the ice. 

Notably, Jarosite needs water to form. Also, formation requires  “iron, sulfate, potassium, and acidic conditions,” according to Science.

Although rare on Earth, the mineral is abundant on Mars.

Discovery of Jarosite on Mars

In 2004, the Opportunity rover found abundant Jarosite on Mars. At the time, NASA concluded the site must have been “soaking wet” in the past.

At the time, the rover’s spectrometer detected Jarosite, a hydrated iron sulfate mineral.

“On Earth, rocks with as much salt as this Mars rock either have formed in water or, after formation, have been highly altered by long exposures to water. Jarosite may point to the rock’s wet history having been in an acidic lake or an acidic hot springs environment,” NASA stated.

Afterward, a lead scientist for Mars exploration, Dr. Jame Garvin, said it pointed to a wet environment. Possibly, Mars could “have been hospitable to life” at one time.

How Did Jarosite Form? 

At first, scientists suggested salty, acidic water evaporated, leaving behind  Jarosite deposits. However, Martian basalt rocks are alkaline. Therefore, the rocks could neutralize the acids needed for formation. Thus, this theory seemed unlikely.

Then, scientists pointed to the idea that the mineral formed in ice pockets on Mars. When the ice was exposed to dust containing iron, sulfate, and potassium, Jarosite formed.

By 2018, researchers found ice deposits near the Red Planet’s surface, possibly pure enough for drinking water.

“You can go out with a bucket and shovel and just collect as much water as you need,” said planetary scientist Shane Byrne. “I think it’s sort of a game-changer.”

Since we know there is ice on Mars today, perhaps minerals continue to form in a similar way?

See more about the Opportunity Rover from NASA below:

Ice Pockets Disturbed by Dust Storms

On Mars, Jarosite is found in large slabs. On the other hand, it’s scarce in Antarctica. Consequently, scientists aren’t sure what explains such a difference in abundance.

What explains why Jarosite slabs are many feet across on Mars versus small traces here? Possibly, the abundance of Martian dust is an explanation?

Now researchers want to use the findings to further investigate Martian mineral formation.

“This is just the first step in linking deep Antarctic ice with the martian environment,” said lead author Giovanni Baccolo from the University of Milano-Bicocca. 

The samples from Antarctica came from East Antarctica’s Talos Dome ice core. Baccolo notes the isolated ice provides a suitable analog for Martia conditions, including:

  • pressure
  • temperature
  • pH
  • chemistry

On February 18, 2021, NASA’s Perseverance rover will touchdown on Mars. If successful, the rover will land in the Jezero Crater. In this location, water may have once been present.

Perseverance brings new technologies, including a helicopter named Ingenuity. Potentially, the rover will soon expand our knowledge about water and possible life on Mars.

See more from LiveScience below:

Featured image: Mars by GooKingSword via PixabayPixabay License with screenshot via YouTube/LiveScience