The planet's stationary crust and lower surface  gravity meant volcanoes could build themselves up  

to staggering heights, like Olympus Mons which  stands nearly three times higher than Mount Everest.

Smaller eruptions continued in some isolated  

pockets as recently as 3 million years ago, but  today the planet seems a much quieter place.  

At least that's what we thought, until scientists  discovered volcanic activity that looks like it  

happened in the relatively recent past, and  their findings could have major implications  

for the search for life on the red planet. Planetary scientists were examining a pair of  

fissures known as Cerberus Fossae that stretch  for nearly 1000 kilometers across a volcanic  

plain in a region known as Elysium Planitia. They're thought to be a relatively young  

geological feature since in some places the walls  are almost vertical, an indication that erosion  

hasn't had time to wear them down to a shallower  angle. Indeed the whole volcanic plain appears  

fairly new, considering the low number of impact  craters compared to other regions of the planet. 

A rough estimate puts its age anywhere between  2.5 million and 500 thousand years old.  

But on closer inspection, one stretch of the  region that's just a few tens of kilometers  

long known as the Cerberus Fossae mantling unit  seems to indicate much more recent activity.

Using visible light and infrared images from NASA's  Mars Reconnaissance and Mars Odyssey Orbiters,  

the researchers spotted a mysterious dark spot  similar to ones on Mercury or the moon. Dark spots  

like this hint at explosive volcanic activity. The deposit of ash and rock sits on solidified  

lava flows, meaning it's from a different time  period than the other volcanic activity. In fact  

it may have happened very recently, judging by  how few impact craters there are in the area. 

How recently?  

This eruption could have  happened within the last 200,000 years, 

and perhaps even just 50,000 years ago. Sure, on a human scale that's a long time,  

but geologically speaking  that's practically yesterday. 

One of the scientists behind the research  said that if the entire history of Mars  

were compressed to a single day, this eruption  would have happened one second before midnight. 

This opens up the possibility that maybe  Mars isn't quite as dead as it seems,  

in a few different ways.  

Maybe there's still magma under the surface, and  all it needs is the right conditions to come out. 

One researcher pointed to an  impact crater just 10 kilometers  

from this newly discovered volcanic feature that  appears to be from about the same time period.  

He speculated the impact may have been the  trigger, though acknowledged it's a longshot.

It's also possible that magma could have come  into contact with ice under Mars' surface  

and the expanding water vapor led to an  eruption.   

Heat from subsurface magma and

that icy substrate could also create conditions  capable of sustaining microbial life in the  

recent past, or perhaps even to this day. But it's not all great news for the search  

for extraterrestrial life: scientists have  long thought methane in Mars' atmosphere was  

a potential biomarker. But volcanoes can also emit  methane, so if Mars is still volcanically active,  

that might be a comparatively anticlimactic  explanation for the methane instead. 

Researchers made this discovery by studying  the planet from orbit, but other probes could  

expand their knowledge. As it happens NASA's  InSight lander is in Elysium Planitia, and  

the seismometer on board has thus far detected two  Marsquakes coming from Cerberus Fossae which could  

be due to moving magma. Unfortunately, one InSight  instrument that would have been really useful for  

just this situation, a heat probe known as the  mole, wasn't able to bury itself deep enough in  

the Martian regolith and after almost two years  of troubleshooting, NASA gave up on the mole in  

January 2021. Perhaps a future mission with an  improved mole will reveal more about how heat  

moves inside the red planet, or maybe we'll get  lucky and something will set off another eruption.  

I just hope it happens soon, and by that I mean  within my lifetime and not 50,000 years from now. 

If you want to learn more about why the InSight  lander's mole couldn't dent Mars's surface by  

why the mission is still awesome  anyway, check out my video on it here. 

With the mixed news about what a volcanically  active Mars could mean for the search for  

extraterrestrial life, are you more or  less optimistic we'll find it on Mars?  

Let us know in the comments, don't forget to  subscribe, and I'll see you soon on Seeker.