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Morgan Butzig and fellow SHERAD team members had made multiple unsuccessful attempts to observe the area suspected of hosting a buried lake. Then the scientists partnered with the spacecraft's operations team at NASA's Central Pollution Laboratory in Southern California, which leads the mission to develop the very large roll capability. Because the radar's antenna is at the back of Colorado, the orbiter's body obstructs its view and weakens the instrument's sensitivity. After considerable work, engineers at JPL and Lockheed Martin Space in Littleton, Colorado, which built the spacecraft and supports its operations, developed commands for a 120-degree roll, roll, a technique that requires careful planning to keep the spacecraft safe, to direct more of SHERAD's signal at the surface. Bright signal, on May 26th, SHERAD performed a very large roll to finally pick up the signal in the target area, which spans about 12.5 miles, or 20 kilometers, and is buried under a slab of water ice, also one mile, or 1,500 meters thick. When a radar signal bounces off underground layers, the strength of its reflection depends on what the subsurface is made of. Most materials let the signal slip through or absorb it, making the return faint. Liquid water is special in that it produces a very reflective surface, sending back a very strong signal. Imagine pointing a flashlight at a mirror. That's the kind of signal that was spotted from this area in 2018 by a team working with the Mars Advanced Radar for Subsurface and Ionospheric Sounding or MARSIS instrument aboard the ESA, European Space Agency's Mars Express Orbiter. To explain how such a body of water could remain liquid under all that ice scientists have hypothesized it could be a briny lake since high salt content can lower water's freezing temperature.