New observations by NASA's Mars Reconnaissance Orbiter indicate that the crust and upper mantle of Mars are stiffer and colder than previously thought.
The results suggest any liquid water that may exist beneath the surface of the planet, and any living organisms in the water, it is lower than scientists had suspected.
"We've found that the rocky surface of Mars is not bend under the weight of the north polar ice cap," said Roger Phillips of the Southwest Research Institute. Phillips is the lead author of a new report this week in the online version of Science. "This means that the planet's interior is stiffer, and thus colder than we thought."
The discovery was with the instrument Shallow radar on the spacecraft, which has the most detailed images at the time of the interior layers of ice, sand and dust from which the north polar cap on Mars. The radar images show long, uninterrupted layers stretching up to 600 miles (1000 km), or about one fifth the length of the United States.
"In our first insight into the polar ice with the radar on Mars Reconnaissance Orbiter, we can clearly see stacks of the icy material, the history of Mars' climate," says Jeffrey Plaut of NASA's Jet Propulsion Laboratory. Plaut is a science team member and a co-author of the paper. "radar" opens up a new route for the study Mars' past. "
The radar images show a smooth, flat border between the ice sheet and the rocky Martian crust. On Earth, the weight of a similar stack of ice would lead to the surface of the planet SAG. The fact that the Mars surface is not bending means that their strong outer shell, or lithosphere, a combination of upper-crust and mantle must be very thick and cold.
"The lithosphere of a planet is the rigid part. On Earth, the lithosphere is the part that breaks during an earthquake," says Suzanne Smrekar, deputy Researchers for Mars Reconnaissance Orbiter at JPL. "The ability of radar to see through the ice sheet and noted that there was no bending of the lithosphere gives us a good idea of today's temperatures inside Mars for the first time."
Temperatures in the outer part of a rocky planets such as Mars increases with the depth in the direction of the interior. The thicker the lithosphere, the more the temperatures gradually rising. The discovery of a thicker Martian lithosphere therefore means that any liquid water lurking in the aquifer beneath the surface should be lower than previously calculated, where the temperatures are warmer. The scientists speculate that all life on Mars in connection with the deep aquifers would also have to be buried deep inside.
The radar images also show four zones of finely distance layers of ice and dust, separated by thick layers of almost pure ice. The scientists think this pattern of thick layers of ice-free represents cycles of climate change on Mars for a period of about one million years. These climate changes are variations in the tilt of the planet's rotation axis and the eccentricity of its orbit around the sun. The observations support the idea that the north polar ice cap is geologically active and relatively young, about 4 million years ago.
The results suggest any liquid water that may exist beneath the surface of the planet, and any living organisms in the water, it is lower than scientists had suspected.
"We've found that the rocky surface of Mars is not bend under the weight of the north polar ice cap," said Roger Phillips of the Southwest Research Institute. Phillips is the lead author of a new report this week in the online version of Science. "This means that the planet's interior is stiffer, and thus colder than we thought."
The discovery was with the instrument Shallow radar on the spacecraft, which has the most detailed images at the time of the interior layers of ice, sand and dust from which the north polar cap on Mars. The radar images show long, uninterrupted layers stretching up to 600 miles (1000 km), or about one fifth the length of the United States.
"In our first insight into the polar ice with the radar on Mars Reconnaissance Orbiter, we can clearly see stacks of the icy material, the history of Mars' climate," says Jeffrey Plaut of NASA's Jet Propulsion Laboratory. Plaut is a science team member and a co-author of the paper. "radar" opens up a new route for the study Mars' past. "
The radar images show a smooth, flat border between the ice sheet and the rocky Martian crust. On Earth, the weight of a similar stack of ice would lead to the surface of the planet SAG. The fact that the Mars surface is not bending means that their strong outer shell, or lithosphere, a combination of upper-crust and mantle must be very thick and cold.
"The lithosphere of a planet is the rigid part. On Earth, the lithosphere is the part that breaks during an earthquake," says Suzanne Smrekar, deputy Researchers for Mars Reconnaissance Orbiter at JPL. "The ability of radar to see through the ice sheet and noted that there was no bending of the lithosphere gives us a good idea of today's temperatures inside Mars for the first time."
Temperatures in the outer part of a rocky planets such as Mars increases with the depth in the direction of the interior. The thicker the lithosphere, the more the temperatures gradually rising. The discovery of a thicker Martian lithosphere therefore means that any liquid water lurking in the aquifer beneath the surface should be lower than previously calculated, where the temperatures are warmer. The scientists speculate that all life on Mars in connection with the deep aquifers would also have to be buried deep inside.
The radar images also show four zones of finely distance layers of ice and dust, separated by thick layers of almost pure ice. The scientists think this pattern of thick layers of ice-free represents cycles of climate change on Mars for a period of about one million years. These climate changes are variations in the tilt of the planet's rotation axis and the eccentricity of its orbit around the sun. The observations support the idea that the north polar ice cap is geologically active and relatively young, about 4 million years ago.
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