Is or was there life on Mars? That is one of the biggest and most hotly debated questions in planetary science. The manner in which the evidence has been searched for is also a topic of much discussion. The Viking landers in the 1970s were the first to look for direct evidence for microbial life still existing in the Martian soil, and the results are still regarded as inconclusive, with both pro and con supporters debating whether the landers actually found living microbes or just unusual soil chemistry. Subsequent lander and rover missions have focused more on determining whether conditions in Mars’ ancient past were habitable and able to support life as we know it, rather than searching directly for evidence of past or present life itself.
Category Archives: Mars
This photo taken a few days ago by the Curiosity rover has been getting a lot of attention. The object near the centre of the image looks a lot like a femur-type bone! This image was taken on sol 719 of the mission, at the entrance to Hidden Valley where Curiosity is ready to start drilling again at a site just a few feet away called Bonanza King.
Some of the most interesting features on the surface of Mars are its gullies, often found on crater walls or other slopes, first seen from orbit back in 2000. They resemble gullies on Earth created by water, but the origin of located on Mars have become the subject of much debate. These gullies appear to be actively forming today, and are not just some relic of past activity that took place millions of years ago. But on Mars, water can’t exist for long on the surface even if it is briny, so how are these gullies being created? New observations from the Mars Reconnaissance Orbiter (MRO) spacecraft suggest that dry ice (frozen carbon dioxide) may actually be responsible. The new findings have been published in the journal Icarus.
The search for evidence of water on Mars, past or present, has been one of the driving forces behind the exploration of the Red Planet for several decades now. While orbiters, landers, and rovers have all found abundant evidence for a lot of water in Mars’ ancient history, the question of whether there could still be any of the wet stuff existing today is still open and unanswered. There are hints, but proof is still elusive. Now, a new study provides new information on how liquid water could be found on Mars’ surface today, albeit in small amounts or for brief periods of time.
The Opportunity rover continues to send back wonderful images of its current location on the rim of Endeavour crater. This new panorama shows the view from Pillinger Point (named after the late planetary scientist Colin Pillinger). The Pillinger Point rock outcrop is on the slopes Solander Point, one of the taller peaks on the rim of the huge crater. What a view! Thanks to James Sorenson who created this panorama from the Opportunity images. The full-size image is available here. There is also a zoomable Gigapan version here.
Curiosity has come across what appear to be a couple of meteorites in Gale crater. No official word yet, but the consensus seems to be that these are indeed meteorites, and fairly large ones, given their similarity to other confirmed meteorites found previously by both the Spirit and Opportunity rovers. Their shininess indicates that they are likely iron meteorites. It is more common to find meteorites on Mars than on Earth, given the thinner atmosphere and slower erosion rates.
The Curiosity rover has taken another great “selfie” image of itself as it sits parked at Mount Remarkable, the butte where it will soon do some more drilling. This is another beautiful montage by Damia Bouic consisting of many separate images spliced together. Mount Remarkable is just out of view to the left and Mount Sharp is in the distance. The full-size image is here.