Mars has been on the news a lot lately, and for good reason. With the historic landing of the Perseverance rover earlier this year and the successful flight of Ingenuity, the first aircraft to fly in a different atmosphere this morning (April 19, 2021), there is no shortage of exciting stories of technical brilliance from those of Man-built wonders exploring the red planet. High above the courageous helicopter, the Mars Reconnaissance Orbiter (MRO) overlooks the Martian landscape on a grand scale. An image released by the High Resolution Imaging Science Experiment (HiRISE), a powerful camera aboard MRO, shows a sunken pit in the polar region of the planet. From the height perspective of the orbiter, it is easy for the mind to transform the concave indentation into a convex, acne-like Mars polarite!
The HiRISE team knows the width, length and height range of MRO for all images. You see the sun angle for the target area, in this case 8 ° above the horizon. This means they can use the location of the shadows in the image to determine that the circular pattern in the layered deposits of minerals and ice (likely both water ice and frozen carbon dioxide) has sunk into the Martian surface. Without this context, it is easy to mistakenly see the object as convex and rise like a whitehead on a red planet.
An artist’s concept of the Mars Reconnaissance Orbiter above the Martian surface. Photo credit: NASA
Part of the reason the image is so easy to associate with acne is its color. As with most spatial photography, it’s important to dig a little deeper into the nature of the color in this image. HiRISE observes in infrared (IR) and some visible light, but does not see any color like your eye does. In order to create images in which the colors correspond to what they would mean to a person, different wavelengths have to be processed, stretched and shifted. The details can be found in this HiRISE document.
A merged image with black and white data and IRB (infrared, red, blue) of the collapsed pit. Note the difference to the RGB image (red, green, blue) at the top of this article. Photo credit: NASA / JPL / University of Arizona
Returning to the picture of the box, we cannot help but ask questions. What process formed this pit? Was there an underground volume of ice that sublimated and left a void that ultimately collapsed? Was this a gradual process or a sudden event? The true nature of the feature remains a mystery for now. Like so many scientific endeavors, this incredible data leaves us with more questions in the future.
HiRISE has produced countless such high-resolution images. It even has the ability to depict the Perseverance Rover on the surface of the planet! A fantastic way to spend hours of your time exploring the nearly endless library of pictures and stories available on the HiRISE website.
An improved HiRISE color image shows the Perseverance Rover on the surface of Mars. Photo credit: NASA / JPL / University of Arizona
Our ongoing exploration of Mars reveals a complex world of diverse geological processes. We see ongoing activity like marsquakes, planet-wide dust storms, and even evidence of underground lakes! We also see evidence of a warm, watery past.
Thanks to programs like MRO, Perseverance and countless others, we understand our dust-red neighboring world better than ever before. No other object in the solar system arouses such curiosity and amazement, and we are fortunate enough to be present during the golden age of Mars exploration.
Leading image: A HiRISE image of the southern polar region of Mars shows a sunken pit on the layered surface. Photo credit: NASA / JPL / University of Arizona
Follow Ralph Crewe on Twitter @RalphCrewe
See Ralph Crewe explore unusual and interesting topics on YouTube
MORE
MRO
HiRISE
Like this:
Loading…
Comments are closed.