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Cool image time! In continuing my exploration of this month’s Mars Reconnaissance Orbiter (MRO) image release, I found two interesting images of small craters, one as part of that image release, the other found completely by accident...The map on the right, taken from the MRO HiRISE archive page, shows the locations of these two images...Both are located in the lava plains that surround the giant volcano Pavonis Mons, the central volcano of the three volcanoes to the east of Olympus Mons.

A very dark spot on Mars could be an entrance to a deep hole or cavern, according to scientists studying imagery taken by NASA's Mars Reconnaissance Orbiter. The geological oddity measures some 330 feet (100 meters) across and is located on an otherwise bright dusty lava plain to the northeast of Arsia Mons, one of the four giant Tharsis volcanoes on the red planet. The hole might be the sort of place that could support life or serve as a habitat for future astronauts, researchers speculated. Must be deep The Mars Reconnaissance Orbiter (MRO) used its High Resolution Imaging Science...

PASADENA, Calif. -- NASA's Mars Odyssey spacecraft has discovered entrances to seven possible caves on the slopes of a Martian volcano. The find is fueling interest in potential underground habitats and sparking searches for caverns elsewhere on the Red Planet. Very dark, nearly circular features ranging in diameter from about 100 to 250 meters (328 to 820 feet) puzzled researchers who found them in images taken by NASA's Mars Odyssey and Mars Global Surveyor orbiters. Using Mars Odyssey's infrared camera to check the daytime and nighttime temperatures of the circles, scientists concluded that they could be windows into underground spaces....

A group of seventh-graders in California has discovered a mysterious cave on Mars as part of a research project to study images taken by a NASA spacecraft orbiting the red planet. The 16 students from teacher Dennis Mitchell's 7th-grade science class at Evergreen Middle School in Cottonwood, Calif., found what looks to be a Martian skylight — a hole in the roof of a cave on Mars.

Aug. 30, 2011 -- On the slopes of the vast Martian shield volcano Pavonis Mons, a rather odd-looking crater resides. Originally spotted by NASA's Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) earlier this year, mission managers decided to zoom in on the suspect feature using the awesome power of the MRO's High Resolution Imaging Science Experiment (HiRISE) camera. Indeed, as HiRISE has confirmed, this is one very odd-looking crater. From a distance, the crater appeared to have a black spot in its center, looking almost like the bulls eye on a dartboard. But on closer scrutiny the spot turned out...

Explanation: What created this unusual hole in Mars? The hole was discovered by chance on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars. The hole appears to be an opening to an underground cavern, partly illuminated on the image right. Analysis of this and follow-up images revealed the opening to be about 35 meters across, while the interior shadow angle indicates that the underlying cavern is roughly 20 meters deep. Why there is a circular crater surrounding this hole remains a topic of speculation,...

What created this unusual hole in Mars? The hole was discovered by chance on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars. The hole appears to be an opening to an underground cavern, partly illuminated on the image right. Analysis of this and follow-up images revealed the opening to be about 35 meters across, while the interior shadow angle indicates that the underlying cavern is roughly 20 meters deep. Why there is a circular crater surrounding this hole remains a topic of speculation, as...

Explanation: What created this unusual hole in Mars? The hole was discovered by chance in 2011 on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars. The hole appears to be an opening to an underground cavern, partly illuminated on the image right. Analysis of this and follow-up images revealed the opening to be about 35 meters across, while the interior shadow angle indicates that the underlying cavern is roughly 20 meters deep. Why there is a circular crater surrounding this hole remains a topic...