On Earth, the study of ice core samples is one among many methods scientists use to reconstruct the history of our past global climate change. an equivalent is true of Mars’ northern polar ice cap, which is formed from many layers of frozen water that have accumulated over eons. The study of those layers could provide scientists with a far better understanding of how the Martian climate changed over time.
This remains a challenge since the sole way we are ready to study the Martian polar ice caps immediately is from orbit. Luckily, a team of researchers from UC Boulder was ready to use data obtained by the High-Resolution Imaging Science Experiment (HiRISE) aboard the Mars Reconnaissance Orbiter (MRO) to graph how the northern polar ice caps’ changed over the past few million years.
Andrew Wilcoski and Paul Hayne, a Ph.D. student and professor from the Laboratory for Atmospheric and Space Physics (LASP) carried out the research. The study that describes their findings recently appeared within the Journal for Geological Research (JGR), a publication maintained by the American Geophysical Union (AGU).
For the sake of their study, Wilcoski and Hayne sought to work out the present state of the Martian North Polar Residual Cap (NPRC), which is significant to understanding the North Polar Layered Deposits (NPLD). Using the high-resolution images gathered by the HiRISE instrument, Wilcoski and Hayne examined the rough features of the NPRC – which incorporates ripples and ridges of varying size and shape.
They then modelled the expansion and recession of NPRC over time supported its interaction with radiation and the way the speed of growth and loss is suffering from the quantity of atmospheric water vapour. What they found was that additionally to causing the formation of rough terrain (ripples and ridges) in an ice sheet, exposure to radiation also will cause ice to sublimate unevenly.
Basically, Mars’ axial tilt, which is liable for it experiencing seasonal changes almost like Earth, also causes one side of those features to sublimate (the Sun-facing side) while the opposite doesn’t. This has the effect of exaggerating these features, resulting in pronounced ridges and valleys that become more pronounced as time goes on.
Wilcoski and Hayne developed the model that depicts the rough features observed by the MRO should measure 10 m (33 ft.) in diameter and 1 m (3.3 ft.) deep. Furthermore, their results demonstrated that because the features age, the spatial wavelength (the distance) between each ripple increases – from 10 to 50 m (164 ft.). As they state in their study: “The results of the observation we carried out on the surface of mounds and depressions on the ice cap suggest that it took 1–10 thousand years to make these roughness features. Our results also suggest that the formation of features on the surface may depend upon when water vapour is present within the atmosphere over the course of a year (e.g., summer or winter).”
A composite image showing alternating layers of ice and sand round the northern polar region, taken by the MRO’s HiRISE camera.
These results are according to the pictures taken by the HiRISE instrument of the Martian North Polar Residual Cap (NPRC). What they indicated is that the rough features observed around Mars’ northern polar ice formed within the last 1000 to 10,000 years, which provides scientists with a start line for reconstructing the climate history of Mars.
Such is that the nature of the Mars. Today, scientists have a reasonably good understanding of the character of the Martian landscape and the way it changes throughout the year. They even have a thought of what it wont to appear as if billions of years ago, because of impeccably-preserved surface features that indicate the past presence of flowing and standing water (rivers, streams, and lakes).
But the intervening period, where the climate transitioned from one to the opposite, that’s where much remains to be learned. within the coming years, robotic missions might be sent to Mars for the sake of studying the ice sheets directly and perhaps even return samples to Earth. within the next decade, as astronauts begin to line foot on Mars, the chance to explore the ice caps could even be possible.