July 20, 1976, will be forever remembered by space enthusiasts. On that day, Viking 1 became the first U.S. spacecraft to land on another planet – in this case, Mars (the USSR Venera 9 spacecraft landed on Venus in 1975). That lander, and Viking 2 which followed it Sept. 3, 1976, paved the way for more complex missions later on, which would begin to finally unlock some of the secrets of the mysterious Red Planet. The two Viking landers, and their counterpart orbiters, were genuine trailblazers, opening up the vast Martian landscape to robotic and human eyes for the first time.
Category Archives: Mars
NASA’s current rovers, Curiosity and Opportunity, are continuing to explore their respective regions of Mars, with new findings that are providing yet more clues as to the geological history and potential past habitability of this fascinating world. They have also both just completed significant steps in their journeys and are now entering new and exciting phases of their missions. Both missions have found yet more evidence that the Mars we see today – cold and dry – was once much wetter and potentially habitable, at least for microorganisms.
Sending human astronauts to Mars is a dream shared by many, but there are still challenges to overcome and the question of just how to accomplish it is a subject of intense debate. Some supporters advocate sending a mission directly to Mars, while others think that returning to the Moon first, for potentially beneficial training, is the way to go. Indeed, former astronaut James Lovell, who flew on two trips to the Moon, has also called for a return to the Moon first. NASA itself has stated its desire to send a crewed mission to a nearby asteroid first, instead of the Moon, going a bit farther into space than the Moon as its idea of preparation for the much longer journey to Mars. A major problem has been that NASA has still not set a firm timetable for such a mission; it wants to go to Mars, but the steps to achieving that goal are still unclear.
Mars’ atmosphere is thin and cold, composed primarily of carbon dioxide along with other trace gases and some water vapour. Evidence has continued to mount, however, that the rarified atmosphere we see today once used to be much thicker and possibly warmer, making it potentially more life-friendly early on. Just how thick and how warm is still a subject of much debate, but there is also another interesting aspect to all of this: New evidence from the Curiosity rover has shown that the Martian atmosphere also used to have a lot more oxygen in it than it does now. Today, only very small traces of oxygen can be found, as opposed to Earth’s oxygen-rich atmosphere. So what does this mean? Could there be biological implications?
Almost, but not quite… the Opportunity rover is now driving to another area on the hillside where it is currently located, after attempting to reach a difficult rock target. The rover wasn’t quite able to get close enough to the target to conduct further studies, after driving on the steepest slope ever encountered by any rover so far, on Knudsen Ridge.
This image from the Curiosity rover on sol 1294 shows some very delicate rock formations on Naukluft Plateau, shaped by blowing Martian sand. The thin atmosphere and lower gravity also help in the formation of such spindly protrusions. Similar ones have also been seen before by the rover.
Another odd but beautiful image of Mars, showing a cone-shaped hill with sand dunes wrapping around it. The formation is in the Ganges Chasma region, and the image was taken by the HiRISE camera on the Mars Reconnaissance Orbiter. Mars has a lot of diverse geology, and this is another good example of that. Original images are here.
The Martian rover Opportunity has become famous for its amazing longevity, but it is not the only one; orbiting spacecraft also usually enjoy long lifespans, and today the Mars Reconnaissance Orbiter is celebrating its 10th year exploring Mars from above. It has helped to revolutionize our understanding of Mars and its complex geological history as well as, of course, sending back thousands of incredible high-res images of the Martian surface.
NASA’s Curiosity rover on Mars may have been stealing the spotlight in recent years, but the other rover, Opportunity, is still going strong after 12 long years. Opportunity has survived the harsh environment and various challenges for much longer than anyone anticipated, and now is taking on a new task: climbing slopes as steep as 30 degrees while searching for deposits of clay minerals which had already been detected by orbiting spacecraft. The region where Opportunity landed, Meridiani Planum, is mostly flat plains, but now on the rugged edge of the huge Endeavour crater, the rover is becoming something of a mountain climber.
Was there ever life on Mars? That is one of the longest-running and most debated questions in planetary science, and while there have been tantalizing clues, solid evidence has been elusive. Now there is a new piece to add to the puzzle, which may be one of the most interesting yet. As first reported on Smithsonian.com, odd formations composed of silica seen by the Spirit rover, nicknamed “cauliflower” for their shapes, may have been produced by microbes, new research suggests. They are very similar to some silica formations on Earth which are found in hydrothermal environments and are known to have formed with the help of microscopic organisms.