"We are not closer to actually detecting life," Dr Patel told BBC News, "but what this finding does is give us the location of where to look on Mars. It is like a treasure map - except in this case, there will be lots of 'X's marking the spots."<doc-sep>Scientists have found a vast lake underneath the surface of Mars, in what they are hailing as a hugely significant breakthrough in the search for alien life on the planet. The discovery marks the first time a stable body of water has been detected on Mars, resolving a decades long debate about whether it has any water at all. It has long been assumed that if water was not present on the red planet, it would almost certainly not be capable of sustaining life. However, according to scientists responsible for the breakthrough, the vast lake lies underneath Mars’s southern pole and stretches 20km across. Nasa's most stunning pictures of space Show all 30 1 /30 Nasa's most stunning pictures of space Nasa's most stunning pictures of space Solar Flare An image from Nasa's Solar Dynamics Observatory (SDO) shows a 200,000 mile long solar filament ripping through the Sun's corona in September 2013 Nasa Nasa's most stunning pictures of space Nasa Celebrates 50 Years of Spacewalking For 50 years, NASA has been "suiting up" for spacewalking. In this 1984 photograph of the first untethered spacewalk, NASA astronaut Bruce McCandless is in the midst of the first "field" tryout of a nitrogen-propelled backpack device called the Manned Maneuvering Unit (MMU) Nasa Nasa's most stunning pictures of space A Hubble Cosmic Couple The spectacular cosmic pairing of the star Hen 2-427 — more commonly known as WR 124 — and the nebula M1-67 which surrounds it ESA/Hubble & NASA Nasa's most stunning pictures of space Veil Nebula Supernova Remnant Nasa's Hubble Space Telescope has unveiled in stunning detail a small section of the Veil Nebula - expanding remains of a massive star that exploded about 8,000 years ago Nasa's most stunning pictures of space The Soyuz TMA-15M rocket launch The Soyuz TMA-15M rocket launches from the Baikonur Cosmodrome in Kazakhstan on Monday, Nov. 24, 2014, carrying three new astronauts to the International Space Station. It also took caviar, ready for the satellite's inhabitants to celebrate the holidays Nasa Nasa's most stunning pictures of space Earth from the ISS From the International Space Station, Expedition 42 Flight Engineer Terry W. Virts took this photograph of the Gulf of Mexico and U.S. Gulf Coast at sunset Nasa Nasa's most stunning pictures of space Black Hole Friday Nasa celebrated Black Friday by looking into space instead — sharing pictures of black holes Nasa Nasa's most stunning pictures of space NuSTAR X-rays stream off the sun in this image showing observations from by NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, overlaid on a picture taken by NASA's Solar Dynamics Observatory (SDO) Nasa Nasa's most stunning pictures of space Cassiopeia A c A false colour image of Cassiopeia A comprised with data from the Spitzer and Hubble Space Telescopes and the Chandra X-Ray observatory Nasa Nasa's most stunning pictures of space Orion Capsule splashes down The Orion capsule jetted off into space before heading back a few hours later — having proved that it can be used, one day, to carry humans to Mars Nasa Nasa's most stunning pictures of space Earth Observations From Gemini IV in 1965 This photograph of the Florida Straits and Grand Bahama Bank was taken during the Gemini IV mission during orbit no. 19 in 1965. The Gemini IV crew conducted scientific experiments, including photography of Earth's weather and terrain, for the remainder of their four-day mission following Ed White's historic spacewalk on June 3 Nasa's most stunning pictures of space Frosty slopes of Mars This image of an area on the surface of Mars, approximately 1.5 by 3 kilometers in size, shows frosted gullies on a south-facing slope within a crater. The image was taken by Nasa's HiRISE camera, which is mounted on its Mars Reconaissance Orbiter Nasa Nasa's most stunning pictures of space Yellowstone from space NASA astronaut Reid Wiseman shared this image of Yellowstone via his twitter account Nasa Nasa's most stunning pictures of space Saturn This near-infrared color image shows a specular reflection, or sunglint, off of a hydrocarbon lake named Kivu Lacus on Saturn's moon Titan Nasa Nasa's most stunning pictures of space Worlds Apart Although Mimas and Pandora, shown here, both orbit Saturn, they are very different moons. Pandora, "small" by moon standards (50 miles or 81 kilometers across) is elongated and irregular in shape. Mimas (246 miles or 396 kilometers across), a "medium-sized" moon, formed into a sphere due to self-gravity imposed by its higher mass Nasa Nasa's most stunning pictures of space Solar Flare An X1.6 class solar flare flashes in the middle of the sun in this image taken 10 September, captured by NASA's Solar Dynamics Observatory Nasa Nasa's most stunning pictures of space Large Magellanic Cloud galaxy An image of the Large Magellanic Cloud galaxy seen in infrared light by the Herschel Space Observatory. Regions of space such as this are where new stars are born from a mixture of elements and cosmic dust Nasa Nasa's most stunning pictures of space Mars Rover Spirit Nasa's Mars Rover Spirit took the first picture from Spirit since problems with communications began a week earlier. The image shows the robotic arm extended to the rock called Adirondack Nasa Nasa's most stunning pictures of space Morning Aurora From the Space Station Nasa astronaut Scott Kelly captured this photograph of the green lights of the aurora from the International Space Station Nasa/Scott Kelly Nasa's most stunning pictures of space Launch of History - Making STS-41G Mission in 1984 The Space Shuttle Challenger launches from Florida at dawn. On this mission, Kathryn Sullivan became the first U.S. woman to perform a spacewalk and Marc Garneau became the first Canadian in space. The crew of seven was the largest to fly on a spacecraft at that time, and STS-41G was the first flight to include two female astronauts Nasa's most stunning pictures of space A Fresh Perspective on an Extraordinary Cluster of Galaxies Galaxy clusters are often described by superlatives.<doc-sep>Just a mile or so beneath the surface, near the south pole of Mars, there is a reservoir of briny water sloshing and churning below layers of ice and rock. This subglacial lake, discovered by a ground-penetrating radar on the Mars Express spacecraft, is about 20 kilometers (12.4 miles) wide and perhaps no more than a meter deep. Its discovery is the latest piece of evidence that suggests water was not only present on Mars in the past but is still flowing in some capacity today. The findings, if confirmed by future observations, would be the most significant discovery of liquid water on Mars to date. Water was not only present on Mars in the past but is still flowing in some capacity today Scientists already had little doubt that there was, at one point, liquid water on Mars, thanks to tiny spherical deposits discovered by the Opportunity rover in 2004 and the comprehensive mineralogy studies conducted by the Curiosity rover. The evidence suggests that vast lakes and rivers dominated the surface of Mars billions of years ago. What's more, tantalizing clues have continued to imply the existence of liquid water on Mars today. Condensation was measured on the Phoenix lander in 2009, and dark streaks spotted on Martian dunes may be evidence of briny water (although more recent examination suggests they could be avalanches of dry sand). This new discovery of a subterranean water deposit, outlined in a new paper in Science, suggests water is indeed underneath the red sands of Mars. Perhaps the Red Planet even has entire subsurface lake systems like those beneath Antarctica. A Breakthrough 15 Years in the Making Mars Express is a European Space Agency probe that has been orbiting the fourth planet from the sun since December 2003. A year and a half after it arrived, the craft deployed two 20-meter radar booms, forming a 40-meter antenna. The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument came online. Since then, MARSIS has been studying Mars with radar signals to learn more about the planet's interior structure and composition. The Mars Express spacecraft with its 40-meter MARSIS antenna deployed. NASA/JPL/Corby Waste In 2007, the instrument detected something interesting. Near the Mars southern polar ice cap, it found strong reflections of radar signals—differences between two layers known as echoes. Strong echoes imply a big difference in what's called dielectric permittivity. There are microorganisms that are capable of surviving well below zero "In the case of Mars, and also in the case of Earth, liquid water is the material that certainly would produce the strongest reflections," says Roberto Orosei, a co-investigator of the MARSIS instrument at the University of Bologna in Italy and lead author of the new study. The strong radar echoes in 2007 wound up being the result of a layer of icy carbon dioxide on the surface of Mars rather than liquid water beneath. "CO 2 ice is very transparent and is able to let the radar pulse penetrate into the ice much better than pure water ice," Orosei says, which is why it mimicked the signal one would expect from underground liquid water. However, he says, many believed the CO2 conclusions "were not the end of the story." Continued observations proved difficult. "The real problem was that observations over the same place in different moments would reveal different results," Orosei says. "So we would see a bright reflection on a certain area one day, and then we would fly over the same area maybe a week later, a month later... and we would not see the same strong reflection we would see ordinarily." Finally, the MARSIS engineers figured out what was thwarting their observations. It was the way their own spacecraft processed the data. "The radar by itself will produce a very high amount of data... [so] it’s necessary to sum together many pulses, more than 100 at a time," Orosei says. This method of averaging the information meant that sometimes the data contained a small, high reflectivity area, while other times it had mysteriously disappeared. "It was something that would really be frustrating in hindsight because we were of course spending years and years debating the possible causes, when in fact the solution really was to change the processing scheme of the spacecraft," Orosei says. Artistic impression of the Mars Express spacecraft probing the southern hemisphere of Mars,superimposed to a color mosaic of a portion of Planum Australe. The study area is highlightedusing a THEMIS IR image mosaic. Subsurface echo power is color coded and deep bluecorresponds to the strongest reflections, which are interpreted as being caused by the presence ofwater. USGS Astrogeology Science Center/Arizona State University/ESA/INAF/Davide Coero Borga Even after this breakthrough, the team spent years taking more observations of the south pole region. Mars Express does not repeat the exact same orbit of Mars, meaning long gaps of time can separate flights over the same area. In addition, the team could gather useful observations only at low altitudes and when the spacecraft was on the night side of Mars because the sun excites the ionosphere of the planet, which blocks radar signals. In total, it took three and a half years to obtain 29 observations of the target location. The scientist who designed MARSIS and who remained most adamant that the signals pointed to a subglacial lake, Giovanni Picardi, passed away during those years. "Professor Picardi... died in 2015, just a few months away from the completion of the data acquisition above the area. So it was really tragic that he could not live to see the end of this work," Orosei says. Even if Picardi wasn't there to see, the MARSIS team realized his dream and revealed a frigid reservoir of liquid water beneath the southern polar ice cap of Mars. The implications for complex systems of subsurface lakes could revitalize the debate about whether microorganisms could exist beneath the surface of Mars to this very day. "It was a long march, a sort of long march through the desert, and we are finally out of it," Orosei says. "It’s like a dark cloud has gone away." Lakes Upon Lakes?<doc-sep>A large reservoir of liquid water has been found deep beneath the frozen surface of Mars near the planet’s south pole, according to a new paper by Italian researchers published in the journal Science. The discovery caps decades of debate over whether such bodies of liquid water exist on Mars today and is sure to fuel speculation about the possibility that life exists on the Red Planet. Water is considered an essential ingredient for life. Mars' south polar ice cap in an image captured the European Space Agency's Mars Express spacecraft. Italian researchers believe a reservoir lies below ice about a mile thick in an area close to the planet's south pole. ESA “I think the chances now of finding a place to look for current life have gone up,” said Scott Hubbard, a professor of astronautics at Stanford University in Stanford, California, who was not involved in the new research. Hubbard, who served as NASA's first Mars program director, called the discovery “thrilling and exciting.” The subglacial lake was detected below a polar region known as Planum Australe by a ground-penetrating radar instrument aboard the European Space Agency’s Mars Express spacecraft, which has been orbiting Mars since 2003. The lake is about 20 kilometers (12 miles) wide and is buried about 1.5 kilometers (1 mile) below the surface, according to an analysis of radar readings made between 2012 and 2015. ESA's Mars Express used radar signals bounced through underground layers of ice to identify a pond of water buried below the surface. ESA “This is just one small study area,” Roberto Orosei, an astronomer at the University of Bologna and the study’s lead author, said in a written statement. “It is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered.” The newfound lake is likely to be extremely cold and salty, according to the research. Those are “not ideal conditions for life to form,” Kirsten Siebach, a planetary scientist at Rice University in Houston, told the Associated Press. But, she added, microbial life has been found in such environments on Earth. Among other extreme environments on our planet, microbes have been found in Lake Vostok, a large subglacial lake in Antarctica. Scientists have long believed that water flowed on Mars billions of years ago, when the planet was hotter, and it's well-established that large deposits of water ice exist there still. Recent research showed that complex organic molecules — the building blocks of life as we know it — are present there. But this is the first time a stable body of liquid water has been detected on Mars. The Italian scientists spent years analyzing the data to make sure the radar readings indicated liquid water — but not everyone is convinced. “I would say the interpretation is plausible, but it’s not quite a slam dunk yet," Jeffrey Plaut, a research scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California, who is not involved in the new research, told Science. But Hubbard called the researchers a “careful group” and said he found the new research convincing — and a likely prelude to additional research. “I think this finding will stimulate other science groups" to reexamine radar data of Mars "to see if they missed anything." Additional reporting by Denise Chow WANT MORE STORIES ABOUT MARS? FOLLOW NBC NEWS MACH ON TWITTER, FACEBOOK, AND INSTAGRAM.<doc-sep>
We now know that there is permanent liquid water on Mars, according to a paper published today in the journal Science. This finding comes from research using the Mars Express spacecraft, which has been orbiting the red planet since December 25 2003. One of the suite of instruments carried by Mars Express is MARSIS (the Mars Advanced Radar for Subsurface and Ionosphere Sounding), which allows researchers to use radar to study features beneath the planet’s surface. Using observations spanning a period of four years, a team of researchers from Italy found evidence of a large lake of salty water, buried 1.5 kilometres beneath Mars’ southern polar cap. That lake is at least 20 kilometres across and seems to be a permanent feature. More than droplets The reason people are excited about this discovery is because everywhere you find liquid water on Earth, you find life. NASA has long espoused a philosophy of “follow the water” in its program of astrobiological research – trying to answer the question “are we alone?” Over the past two decades, we have seen mission after mission travel to Mars. Some, like Mars Express, are orbiters. Others (such as the incredible Spirit and Opportunity) are rovers. A unifying theme across those missions has been their attempts to see whether Mars once had the right conditions for life to exist and thrive. Through them we have found abundant evidence that Mars was once warm and wet. We also have evidence that liquid water can still be found on the surface of Mars from time to time. But, until today, the evidence of modern water all pointed towards fleeting moments - droplets condensing on the Mars Phoenix lander, or evidence of brief outflows of salty water in Martian valleys. Compared with today’s discovery, those earlier findings are a drop in the ocean. Mars has a lake The latest observations reveal something remarkable: a salty lake buried deep beneath the ice, which seems to be a permanent feature rather than a transient phenomenon. The comparison that springs to mind are the myriad lakes buried under the ice of Antarctica. So far more than 400 such lakes have been found beneath the surface of the frozen continent. Perhaps the most famous is Lake Vostok – one of the world’s largest lakes, buried and hidden away. But the one to which I want to draw your attention is Lake Whillans. Lake Whillans is buried some 800 metres below the ice in West Antarctica. In 2013, a team of researchers succeeded in drilling down into the lake and recovering samples. What did they find? That it was teeming with microbial life. In other words, the best Earth-based analogues for the newly discovered Martian lake are not just habitable, they are inhabited. Where there’s water, there’s life. Is there life on Mars? Finding this new lake, buried beneath Mars’ south pole, is another exciting step on our journey of discovery of the red planet. Could there be life there, beneath the ice? The short answer is that we still don’t know. But it seems like the ideal place to look. What we do know is: Mars was once warm and wet, potentially with oceans, lakes and rivers. On Earth, where you find water, you find life. The transition from warm, wet Mars to the cold and barren Mars we see today occurred over millions of years. Life adapts to changing environments, so long as that change is not too fast or dramatic. So what do you get if you put all that together? Well, this is where things get speculative. But let’s imagine that in the far distant past Mars had life. Perhaps the life originated there, or maybe it was delivered from Earth, hitching a ride on a meteorite. Once life is established, it is amazingly hard to get rid of. Over millions of years, Mars cooled and its water became locked in permafrost. Its atmosphere thinned and it became the red planet we see today. But maybe, just maybe, that life would have been able to follow the water - to move underground, where it might have found a niche in a dark salty lake, buried beneath the ice of Mars’ southern polar cap. That’s all well and good, but what next? That’s all speculation, but it shows the kind of thought processes that have driven our ongoing exploration of Mars for the past couple of decades.