4 Strangest Things Found on Mars So Far | Unveiled

4 Strangest Things Found on Mars So Far

Mars, the dusty red planet, sits relatively right next door to us—yet our neighbour still remains a bit of a mystery. A mystery we’ve only recently begun to explore in earnest. In just a few decades, we’ve uncovered a lot to help us fill in our gaps of knowledge, but we’ve also discovered quite a bit that’s left scientists scratching their heads.

This is Unveiled, and today we’re exploring: the 4 strangest things found on Mars so far.

In the mid-1960s, NASA launched the first successful missions to Mars with the Mariner program. The Soviets soon followed suit. Our exploration of the Red Planet began with flybys and orbiters, before progressing to landers and rovers. These rovers have been the real breakthrough in Mars exploration. Equipped with wheels, rovers have the ability to move about the surface of the planet, collecting samples, performing tests, and capturing breathtaking photos.

In 1997, the first Mars rover, Sojourner, which was about the size of a microwave, touched down on the planet’s surface in the Ares Vallis area. Sojourner’s mission was to investigate the planet’s geology and the possible presence of liquid water on the surface in the past. This was essentially the same mission that Spirit and Opportunity had. These twin rovers landed on the planet in 2004 in Gusev Crater and Meridiani Planum area respectively, and went on to capture the first colour photos of the surface of Mars. In 2012, Curiosity landed in Gale Crater. The largest rover sent to date, Curiosity was the size of a small SUV. The samples it took from Gale Crater proved that Mars, at one point, had the ingredients necessary for microbial life to survive. However, it also discovered that Mars had dangerously high levels of radiation.

The latest rovers to land were Perseverance in February 2021, and China’s Zhurong a month later. Having touched down in Jezero Crater, Perseverance is looking for signs of past life on the planet. It’s also running tests to help NASA plan for potential human missions to Mars. These tests include a revolutionary method to extract breathable oxygen from Mars’ atmosphere. Accompanying Perseverance is a mini-helicopter scouting out locations of interest, Ingenuity.

These missions have all helped scientists better understand our neighbour, but they’ve also uncovered some strange mysteries as well.

One of the strangest, and perhaps most terrifying, phenomena that have been discovered are invisible dust devils. In 2018, NASA launched its InSight Mission, a robotic lander that installed a seismometer on the surface. Findings published in Nature Geoscience and Nature Communications the following year revealed some truly bizarre weather. Dust devils are caused by heat and sudden air pressure changes, resulting in swirling vortexes of air that are similar to small tornados. Dust devils occur in hot, dry locations on Earth, but are typically pretty small. On Mars, however, they are on average three times bigger and occur a lot more frequently. More frightening, however, is the fact that some of them seem to be invisible.

Normal dust devils kick up dust (hence their name), and these have been sighted on Mars by rovers. But InSight couldn’t capture a single picture of one despite detecting upwards of 10,000 of them. And it’s not for lack of dust, as Mars is one of the dustiest places around. High in the atmosphere, the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (or HiRISE) showed tracks of dirt devils all around InSight. But InSight itself couldn’t see anything. This has scientists puzzled. Mars’ weather will be one of the most significant challenges for humans, and understanding how their storms work will be critical to any crewed mission to the planet.

Speaking of life on Mars, Curiosity has captured strange, periodic emissions of methane from the planet—a gas often associated with life. Large amounts of methane, at least on Earth, are usually produced by organic lifeforms—livestock in particular—digesting plants and exhaling the gas. And while Curiosity measured a consistent small background amount of methane—about 1 part for every 2 billion parts Martian air—it would also pick up spikes of 10 to 20 times that amount. If this were Earth, those kinds of levels of methane would indicate life. There certainly isn’t any livestock on Mars, so what could be causing these spikes? Could there be microbes beneath the surface? Or is there a geological explanation?

Another wrinkle in the mystery came from the European Space Agency’s ExoMars Trace Gas Orbiter. It hasn’t detected any methane higher up in Mars’ atmosphere. So on the ground, there are huge spikes in methane, but in the atmosphere there are none. This was even more puzzling. However, in 2019, scientist John E. Moores from York University in Toronto came up with a theory. He noticed that Curiosity did its measurements at night, whereas the Trace Gas Orbiter did its testing during the day. He figured that as the planet cooled at night, methane collected near the surface. But as the day grew hotter, the gas would rise and mix with other gases, becoming virtually undetectable. The Curiosity team immediately set about to test this hypothesis. And, sure enough, it was correct. The Curiosity team ran their test during the day and detected no methane.

However, this doesn’t solve why the methane is rising and falling in the first place. Scientists suspect that methane is seeping out of craters, but methane is a stable molecule that should linger for about 300 years on Mars – meaning it should be detectable in the atmosphere. So, is there also something destroying Mars’ methane?

Curiosity isn’t the only rover to have discovered something unusual. Despite only being on the surface of Mars for a short time, Perseverance has already stumbled across something quite strange. In March of 2021, the Perseverance team Tweeted out a picture of a truly bizarre-looking rock that the rover came across. About six inches long, blue-ish green, smooth and full of holes, this rock has scientists stumped. Where did it come from? It looks nothing like anything else found in the area. Did it originate on a different part of the planet? If so, how? Perhaps ancient waterways brought it to its current location. Or perhaps it’s a meteorite. Some on the Perseverance team theorize that it could be localized bedrock, weathered out over time. They’ve been studying the rock using Perseverance’s SuperCam. Sitting atop the rover’s mast, SuperCam is a high-powered laser that can blast rocks up to 23 feet away. It then uses its cameras and spectrometers to analyze the composition of the vaporized rock. So perhaps sooner rather than later we’ll have an answer as to where this unique rock came from.

Another truly bizarre geological formation was discovered in 2011 by NASA's Mars Reconnaissance Orbiter. It captured a photo of a giant hole on the slope of a large shield volcano called Pavonis Mons. While the surface of Mars is pockmarked with all sorts of holes, craters and depressions, this one was unlike any other. The image looks more like a collapsed, hollow mountain than an impact crater. And unlike almost all impact craters, this hole appears to be deep—very deep.

Scientists’ best guess is that it’s a skylight to a lava tube. This happens when lava solidifies on the surface but continues to flow underneath. When the lava retreats, it leaves behind empty tubes. Lava tubes occur on Earth but aren’t nearly as immense as this one spotted on Mars. With an opening 115 feet across and a cavern about 92 feet deep, this is far larger than anything on Earth. Stranger still, it’s surrounded by a conical crater. No lava tube opening on Earth is like this. This has scientists puzzled and intrigued. Holes like these are of particular interest in that they could provide good shelter from Mars’ extreme radiation. That makes them ideal candidates to explore for remnants of life, or for utilizing as shelter for human explorers.

Our understanding of Mars is evolving quickly. As each new mission is launched and more data is sent back to Earth, we learn more not just about the planet, but the formation of our own solar system. Perseverance has just started its mission to find signs of life and test ways in which humans could survive and thrive on the planet. We completed the first-ever test of a powered flight vehicle on another planet with Ingenuity. Who knows what we will discover in the near future? More mysteries will certainly arise, but these will also lead to further discoveries.

And those are the four of the strangest things found on Mars so far.