UAHiRISE (NASA MRO)

Tyrrhena Terra is centered south of the Martian equator and immediately northeast of the giant Hellas basin. There are also possible clays in this region. NASA/JPL/University of Arizona (260 km above the surface and the scene is less than 1 km top to bottom and north is to the right.) https://www.uahirise.org/ESP_013898_1730

Bright ripples line the topography in this region, formed within a past climate. Dark dunes and sand streaks (composed of basaltic sand) have moved and filled lower areas, pushed by more recent winds from the top towards the bottom of this image. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_022250_2065

We can see higher standing ridges in this image, which indicates they are composed of more resistant material compared to the surrounding terrain. Roddy Crater is south of the western end of Valles Marineris (Mars). NASA/JPL/University of Arizona (262 km above the surface and the scene is under 5 km across.) https://www.uahirise.org/ESP_050653_1575

Some HiRISE images show strange-looking formations. Sometimes it helps to look at Context Camera images to understand the circumstances of a scene, which shows an impact crater with a central peak, and a collapse depression with concentric troughs just north of that peak. Our HiRISE picture is a close-up of one of those troughs, along with channels draining into the depression. On the floor of the trough is some grooved material that we typically see in middle latitude regions where there has been glacial flow. These depressions with concentric troughs exist elsewhere on Mars, and their origins remain a matter of debate. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_053734_1515

Gullies on Martian sand dunes, like these in Matara Crater, have been very active, with many flows in the last ten years. The flows typically occur when seasonal frost is present. Here, we see frost in and around two gullies, which have both been active before. There are no fresh flows so far this year, but HiRISE will keep watching! (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_054026_1300

This image shows a roundish crater with three channels breaching the rim and extending to the south. The crater has been filled by sediments and may have been an ancient lake. When the water began to overtop the crater rim, it would rapidly erode a channel and, at least, partially drain the lake. (Audio: www.tregibbs.com. Black and white images are 5 km across.) https://www.uahirise.org/ESP_053670_2180

The slip faces of these Martian polar dunes primarily face southeast but there also other orientations. Or perhaps, they're pondering their future as we ponder them... NASA/JPL/University of Arizona (319 km above the surface. The scene is 5 km top to bottom and north is to the right.) https://www.uahirise.org/ESP_050601_2555

This scene is located within a large impact crater to the west of Kaiser Crater. Both are located in the Noachis quadrangle of Mars. NASA/JPL/University of Arizona (252 km above the surface and the enhanced color scene is less than 1 km top to bottom and north is to the right.) https://www.uahirise.org/ESP_050559_1300

This clip features the enhanced color strip of an observation of a section of Sirenum Fossae (Mars), which is an over 2,700 km trough on the Red Planet. NASA/JPL/University of Arizona (257 km above the surface, less than 1 km top to bottom and north is to the left.) https://www.uahirise.org/ESP_013353_1475

This observation shows the plains to the northwest of the Argyre Region (Mars) with possible olivine-rich terrain. NASA/JPL/University of Arizona (256 km above the surface. Scene is less than 1 km top to bottom and north is to the right.) https://www.uahirise.org/ESP_013336_1430

This image is located within the massive Valles Marineris canyon system (Mars). NASA/JPL/University of Arizona (265 km above the surface, and the scene is less than 1 km across.) https://www.uahirise.org/ESP_050391_1755

Are the ridges fluvial sedimentary rock bodies and is there layering within the pits? NASA/JPL/University of Arizona (328 km above the surface. Enhanced color is less than 1 km top to bottom and north is to the right.) https://www.uahirise.org/ESP_050427_2200

Based upon where the layers are exposed, we can tell that the dark layers formed first followed by the light layers. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/PSP_007917_1650

How do these ridges stand in positive relief after billions of years of erosion? (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_053752_1540

Some of the ground has parallel dark and light stripes and within those dark stripes are piles of boulders at regular intervals. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_053924_2550

“As her fate, she accepted the world of ice, shining, shimmering, dead; she resigned herself to the triumph of glaciers and the death of the world.” ― Anna Kavan, Ice NASA/JPL/University of Arizona (274 km above the surface. Scene is 5 km across.) https://uahirise.org/ESP_050218_0930

NASA/JPL/University of Arizona (265 km above the surface, less than 1 km top to bottom and north is to the right.) https://uahirise.org/ESP_050338_1720

Alluvial fans on Mars are thought to be ancient and record past episodes of flowing water. NASA/JPL/University of Arizona (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_054117_1585

Barlow Crater is in the mid latitudes of Mars, to the northwest of the Hellas impact basin. It is *not* named after Mr. Barlow in "Salem's Lot." NASA/JPL/University of Arizona (256 km above the surface; scene is less than 1 km top to bottom and north is to the right.) https://www.uahirise.org/ESP_013053_1660

Worn away by the wind, the bedrock reveals its geologic history. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/PSP_003418_1865

These light-toned mounds generally contain sulfates, which are salts of sulfuric acid that form when water is evaporating. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_016712_1760

While it certainly hasn't gone anywhere, a new image of the Phoenix lander shows us how much change has occurred in five Mars years. (Audio: www.tregibbs.com. Enhanced color images are 1 km across.) https://uahirise.org/ESP_053451_2485

One upside of recognizing and noting this ice is that future astronauts will have plenty of drinking water. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_053642_2225

This crater may have formed in a region rich in ground water, which flowed down its wall and eroded numerous gullies in the process. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_021741_1415

“I’m fascinated by the narrative of geology...I keep a rock hammer in my car.” – Marianne Wiggins Breccias are large concentrations of jumbled rock. NASA/JPL/University of Arizona (278 km above the surface. Scene is 5 km across) https://www.uahirise.org/ESP_050323_1875

This observation shows bedrock that is several kilometers below the top of the giant Valles Marineris canyons. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_013784_1710

As beautiful as this pattern is, the streaks will fade away over decades as more dust settles out of the Martian sky. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_053518_1955

Wait, what? (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_053222_2150

An excellent candidate for recurring slope lineae. Will we see them change over time? NASA/JPL/University of Arizona (268 km above the surface. Enhanced color is less than 1 km top to bottom and north is to the right) https://www.uahirise.org/ESP_049268_1695

Over time thin cracks develop and coalesce into a honeycomb network, with a few meters spacing between neighboring them. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/PSP_008883_2245

Actually, this is in Valles Marineris, where we find some very high thermal inertia surface and possible bedrock exposure. NASA/JPL/University of Arizona (264 km above the surface, about 5 km across) https://uahirise.org/PSP_004133_1665

This erosion has produced several small mesas and exposed light-toned material that may differ in composition from the surrounding material. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://ESP 012729_1830

Ladon Basin was a large impact structure that was filled in by the deposits from Ladon Valles, a major ancient river on Mars. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_013045_1615

These blocks of layered material have been eroded by the wind into the scenic landscape we see here. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_012548_1980

This is right outside of Casil Crater (on the left) which is within the much larger Gusev Crater. NASA/JPL/University of Arizona (262 km above the surface) https://www.uahirise.org/PSP_005812_1650

NASA/JPL/University of Arizona (262 km above the surface. Enhanced color image is about 1 km top to bottom and north is to the right.) https://www.uahirise.org/PSP_006882_1685

A crawl over Kaiser Crater. The blue represents basaltic sand. NASA/JPL/University of Arizona (251 km above the surface, about 1 km across.) https://www.uahirise.org/PSP_006609_1330

NASA/JPL/University of Arizona (260 km above the surface and North is to the right, less than 1 km top to bottom.) https://www.uahirise.org/ESP_050279_1420

This image of northern Meridiani Planum shows faults that have disrupted layered deposits. Some of the faults produced a clean break along the layers, displacing and offsetting individual beds. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_052893_1835

On the crater’s floor is a network of channels connecting a series of irregular shaped pits that resemble terrestrial beaded streams. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_052628_2310

NASA/JPL/University of Arizona (311 km above the surface) https://www.uahirise.org/ESP_050257_1880

If the structure in this observation is a moraine, we should expect to find two sources of debris converging in the valley. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_050004_2170

Much like the terrestrial examples, this ice sheet is layered and scientists refer to it as the South Polar layered deposits. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/ESP_023616_1005

NASA/JPL/University of Arizona (267 km above the surface; scene is 5 km across.) https://www.uahirise.org/ESP_050229_1330

Was the collapse a structural one caused by ground ice? (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_049999_1450

The diversity of exposed bedrock made this location an ideal candidate for exploring a potentially water-rich ancient environment that might have once harbored life. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://uahirise.org/PSP_009115_2040

NASA/JPL/University of Arizona (288 km above the surface. Scene is 5 km across. ) https://www.uahirise.org/ESP_050161_1540

In addition to these features, there might be a number of processes shaping the landscape today. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.) https://www.uahirise.org/ESP_052430_1425

Though often beautiful to look at, yardangs are not permanent and will be eroded away by the persistence of the Martian winds. (Audio: www.tregibbs.com. Black and white images are 5 km across; enhanced color images are 1 km.)

This area is a very good candidate area for recurring slope lineae (or, briny flows) which could be at their longest extent here. NASA/JPL/University of Arizona (261 km above the surface. https://www.uahirise.org/ESP_050101_1745)