Categories: ImagesMarsWater

Ice Peeks out of a Cliffside on Mars

The HiRISE (High-Resolution Imaging Science Experiment) camera on the Mars Reconnaissance Orbiter has captured another beauty. This time the image shows water ice peeking out from a cliffside on Mars. A layer of sediment obscures most of the ice, but fingers of it are visible.

Mars likely had ancient oceans, and the remnants of all that water are hidden as ice. It’s mostly buried in the planet’s crust. In this image, it’s under a thick layer of sediment. The image is from Mars’ Milankovic Crater, a prominent impact crater that sits alone to the north of Olympus Mons, Mars’ tallest volcano, and the tallest volcano in the Solar System.

This topographical image of Mars shows the three volcanoes of Tharsis Montes, with Alba Mons to the north, and Olympus Mons to the northeast. Well above Olympus Mons is Milankovic crater, almost alone in the flat plain of Vastitas Borealis. Image Credit: NASA.

Mars’ ancient oceans were turned to ice when Mars lost its atmosphere between about 3.7 billion to 4.2 billion years ago. The water now exists mostly as subsurface ice. A 2018 study found evidence of a complex of liquid saltwater lakes under the south polar region, which generated a lot of excitement. In 2019, researchers proposed that magma activity in the preceding one million years created enough heat to maintain that water in liquid form. Then in 2021, another study pointed out that the discovery of the subglacial polar lakes could be explained by other phenomena.

The existence of subglacial lakes of water on Mars will likely remain controversial for a long time. But the existence of subsurface water ice isn’t controversial. We’ve seen it.

When NASA’s Phoenix Lander arrived on Mars in 2008 its retro-rockets exposed the shallow subsurface. Scientists believe that the white patch is water ice. Image Credit: By NASA/Jet Propulsion Lab-Caltech/University of Arizona/Max Planck Institute – This image or video was catalogued by Jet Propulsion Laboratory of the United States National Aeronautics and Space Administration (NASA) under Photo ID: PIA10741., Public Domain, https://commons.wikimedia.org/w/index.php?curid=4143566

Mars’ water exists as ice, locked into the planet’s crust at varying depths, except for the possibility of liquid water heated by magma existing under the polar region. Scientists think that there are at least 5 million cubic kilometres of ice underground, with even more at depths beyond the capabilities of our current remote sensing instruments. Some of that ice is visible in the HiRISE image, peeking out from under a layer of sediment.

The leading HiRISE image above is an infrared-red-blue image that highlights the presence of the ice. The RGB image below is more representative of what human eyes would see.

This image resembles more closely what the ice looks like to human eyes, but doesn’t highlight the presence of the ice as well as the IR image. Image Credit: NASA/JPL/UArizona

We’ve improved our understanding of Martian water dramatically in recent years. A 2021 study showed that between 30% and 90% of Mars’ original water may be frozen under the surface, with large deposits in the Arcadia Planitia region. In 2019 NASA made a map of Martian water across the planet’s surface. NASA said that some of the water is only 30 cm (12 inches) deep, making it easily accessible to future explorers.

It’s clear that humanity is reaching out to Mars. With our orbiters, landers, and rovers, we’re piecing together the planet’s history. Mars was once wet and warm and may have harboured life. Future sample-return missions might confirm the presence of microbial fossils. That would be a huge discovery, worthy of all the fanfare it would no doubt generate.

But we want to set foot on Mars, sometime, somehow. And when that happens, our explorers will know where to find water.

More:

Evan Gough

Recent Posts

The Closeby Habitable Exoplanet Survey (CHES) Could Detect Exoplanets Within a few Dozen Light-Years of Earth Using Astrometry

A team of Chinese researchers has proposed a new mission to find Earth-like planets in…

1 day ago

Dust Storms on Mars Happen When the Planet Can’t Release its Heat Fast Enough

New research led by the USRA has found a possible explanation for planet-wide Martian dust…

2 days ago

Spinlaunch Hurled a Test Rocket Into the air. See What it Looked Like From the Payload’s Point of View

Can watching a video give you motion sickness?  If so, a commercial launch company called…

3 days ago

Is This the Future of the Milky Way?

The central region of the giant elliptical galaxy NGC 474. It's set against a backdrop…

3 days ago

Plants can grow in lunar regolith, but they’re not happy about it

NASA is sending astronauts back to the Moon by the end of this decade, and…

3 days ago

The Lunar Eclipse, Seen From the International Space Station

If you were able to witness the lunar eclipse on May 15-16, 2022, the view…

3 days ago