A balloon carrying sensors designed to detect the faint traces left by alien life on other planets has been sent on a mission high into the Earth's atmosphere. The Planetary Atmospheres Minor Species Sensor (PAMSS) spent more than an hour at 105,000 feet above the Earth's surface taking measurements before parachuting safely back to the ground. The experimental sensor, developed by researchers at Nasa and the University of Central Florida, was being tested ahead of plans to send the device to other planets. The high altitude balloon above carried the new highly sensitive instrument 19.8 miles into the atmosphere . Capable of detecting traces of gas at parts per trillion - far more sensitive from current technologies - it could reveal the existence of life on other planets. Even low levels of methane on a planet could indicate that there is life there breaking down organic material. The PAMSS sensor is launched into the air beneath a high-altitude balloon from Tucson, Arizona . Professor Robert Peale, a physicist at the University of Central Florida who is leading the project, said: 'Our sensor has the potential to detect specific gases at extremely low concentrations. 'Metabolic byproducts of life include characteristic gases like methane, which on Mars would be a very low concentrations.' Professor Peale and his team launched their sensor, which uses an infrared laser the size of a grain of salt, on a high altitude balloon from Tucson, Arizona, on Sunday. The toaster-sized device uses a technique known as 'intracavity laser absorption spectrometry' to detect small amounts of gas. Most atmospheric probes used to day are unable to measure the concentration of trace vapours or gases. However, Nasa hopes that by using the PAMSS they may be able to detect small amounts of methane on other worlds like Mars, Jupiter's moon Europa and Saturn's moon Enceladus. Low levels of methane have already been detected on Mars with hot spots where levels are thought to spike. Scientists now want to explore these more closely in the hope that here may still be life existing somewhere beneath the surface. The test on the balloon was designed to show that the PAMSS could function in the extreme cold and low pressures of near space. In the stratosphere temperatures fall as low as -75°F (-59°C). Scientists claim to have discovered evidence that suggests there may be alien life living high up in our own atmosphere. Researchers from the University of Sheffield and Buckingham University claim to have gathered samples that show microscopic organisms are living 16 miles up in the stratosphere. Using a high-altitude balloon, they gathered samples of dust and other microscopic debris high above the Earth's surface and say they found fragments of single celled algae known as a diatom. They argue that this could be the first evidence to show how life may have arrived on Earth from space, perhaps carried here by meteorites. It is not the first time organisms have been found in the atmosphere and indeed the skies are thought to be teeming with microscopic life. Scientists working with Nasa found 314 different types of bacteria living in the atmosphere up to five miles above the Atlantic Ocean and the US in 2012. They concluded the bacteria, which accounted for 20 per cent of the particles they collected, were carried up into the atmosphere by wind currents. However the team believe the device could also have applications on Earth to help monitor changes in the ozone layer as well as helping to detect traces of gas in breath tests to help diagnose disease. Professor Peale said: 'The flight was very successful. The balloon reached 105,000 ft for over one hour, achieving objectives. 'The instrument parachuted safely back to earth and I was able to join the recovery team. 'Our instrument functioned, and a first look at the data show expected types of numbers. It will take a while to analyze all of the data.' The Planetary Atmospheres Minor Species Sensor, shown above sitting on top of laboratory equipment being used to calibrate the device, is about the size of a domestic toaster and can detect minute traces of gases .
Planetary Atmospheres Minor Species Sensor can detect tiny traces of gas . It can detect just one molecule of methane among a trillion other molecules . Toaster-sized instrument flew 19.8 miles above Earth's surface in first test . It spent an hour at 105,000 feet collecting data before parachuting to Earth . Nasa hope to send it to Mars and other planets to search for signs of life .