NASA's Mars Reconnaissance Orbiter has shed new light on a long-standing Martian mystery, but the answer is not what scientists had hoped for. For years, researchers have been fascinated by a suspicious feature at the Red Planet's south pole, which was thought to be an underground lake. However, a recent study using advanced radar techniques has revealed that this area may actually be a layer of rock and dust.
The discovery was made possible by NASA's Mars Reconnaissance Orbiter (MRO), which employed a special maneuver called a "very large roll" to enhance the power of its Shallow Radar (SHARAD) instrument. This allowed the radar signal to penetrate deeper underground, providing clearer images of the subsurface. The technique has proved so effective that scientists are eager to use it at other previously observed sites where buried ice may exist.
Led by Gareth Morgan and Than Putzig, researchers had made multiple attempts to observe the suspected lake, but were unable to detect any signals using standard radar techniques. They partnered with the spacecraft's operations team at NASA's Jet Propulsion Laboratory in Southern California to develop the very large roll capability, which requires careful planning to keep the spacecraft safe.
Using this new technique, MRO detected a faint signal from the area suspected of hosting a buried lake, but it was significantly weaker than the signal received by the European Space Agency's Mars Express orbiter using its Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument in 2018. The team had hypothesized that the lake could be briny, with high salt content lowering water's freezing temperature.
However, the new data suggests that something else is causing the quirky radar signal detected by MARSIS. Morgan and Putzig are cautious not to dismiss the lake hypothesis entirely, but say that it becomes increasingly difficult to support the idea of a liquid water lake given the latest findings.
The team is now excited to apply this new technique to other scientifically interesting regions of Mars, such as Medusae Fossae, a sprawling geologic formation on the planet's equator. The potential discovery of water resources near the Martian equator makes it an attractive location for future human exploration, with the equator being exposed to more sunlight and warmer temperatures.
The study was published in Geophysical Research Letters on November 17 and highlights the power of advanced radar techniques in uncovering the secrets of Mars' subsurface.
The discovery was made possible by NASA's Mars Reconnaissance Orbiter (MRO), which employed a special maneuver called a "very large roll" to enhance the power of its Shallow Radar (SHARAD) instrument. This allowed the radar signal to penetrate deeper underground, providing clearer images of the subsurface. The technique has proved so effective that scientists are eager to use it at other previously observed sites where buried ice may exist.
Led by Gareth Morgan and Than Putzig, researchers had made multiple attempts to observe the suspected lake, but were unable to detect any signals using standard radar techniques. They partnered with the spacecraft's operations team at NASA's Jet Propulsion Laboratory in Southern California to develop the very large roll capability, which requires careful planning to keep the spacecraft safe.
Using this new technique, MRO detected a faint signal from the area suspected of hosting a buried lake, but it was significantly weaker than the signal received by the European Space Agency's Mars Express orbiter using its Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument in 2018. The team had hypothesized that the lake could be briny, with high salt content lowering water's freezing temperature.
However, the new data suggests that something else is causing the quirky radar signal detected by MARSIS. Morgan and Putzig are cautious not to dismiss the lake hypothesis entirely, but say that it becomes increasingly difficult to support the idea of a liquid water lake given the latest findings.
The team is now excited to apply this new technique to other scientifically interesting regions of Mars, such as Medusae Fossae, a sprawling geologic formation on the planet's equator. The potential discovery of water resources near the Martian equator makes it an attractive location for future human exploration, with the equator being exposed to more sunlight and warmer temperatures.
The study was published in Geophysical Research Letters on November 17 and highlights the power of advanced radar techniques in uncovering the secrets of Mars' subsurface.