A breathtaking new panorama captured by NASA’s 2001 Mars Odyssey orbiter showcases one of the most impressive geological features of the Red Planet: Arsia Mons. This massive volcano emerges from a thick layer of clouds just before dawn, providing a unique view that highlights the beauty and complexity of Mars' atmosphere. Arsia Mons, along with two other prominent volcanoes, collectively known as the Tharsis Montes or the Tharsis Mountains, frequently finds itself surrounded by clouds composed of water ice, especially during the early morning hours.
This remarkable panorama marks a significant milestone as it is the first time one of Mars' colossal volcanoes has been imaged on the planet's horizon. This perspective mirrors the breathtaking views astronauts experience when gazing down at Earth from the International Space Station. Launched in 2001, the Odyssey mission is now the longest-running interplanetary mission and continues to provide valuable scientific data, particularly with its recent series of high-altitude images of the Martian horizon.
To capture these stunning images, the Odyssey spacecraft rotates 90 degrees while in orbit, allowing its specialized camera to focus on Mars' surface. This technique enables scientists to study dust and water ice cloud layers while tracking seasonal changes across the planet. “We’re seeing some really significant seasonal differences in these horizon images,” stated Michael D. Smith, a planetary scientist at NASA’s Goddard Space Flight Center. “It’s giving us new clues to how Mars’ atmosphere evolves over time.”
Grasping the dynamics of Mars’ clouds is crucial for understanding the planet’s weather patterns, including the formation of dust storms. This knowledge is essential for planning future missions, including crucial operations involving entry, descent, and landing on Mars. The data obtained from these images could significantly enhance our understanding of Martian atmospheric phenomena.
The latest horizon image, taken on May 2, prominently features Arsia Mons, which towers at an impressive height of 12 miles (20 kilometers), making it roughly twice as tall as Earth’s largest volcano, Mauna Loa, which stands at 6 miles (9 kilometers) above sea level. As the southernmost of the Tharsis volcanoes, Arsia Mons is also noted for being the cloudiest of the three, with clouds forming as air expands while ascending the mountain and then rapidly cools. The thickness of these clouds is especially pronounced during aphelion, the time when Mars is farthest from the Sun.
During this period, a band of clouds known as the aphelion cloud belt stretches across the planet’s equator, prominently displayed in Odyssey’s latest panorama. “We picked Arsia Mons hoping we would see the summit poke above the early morning clouds. And it didn’t disappoint,” remarked Jonathon Hill from Arizona State University, who leads operations for Odyssey’s camera, the Thermal Emission Imaging System (THEMIS).
The THEMIS camera is equipped to observe Mars in both visible and infrared light, which aids scientists in identifying areas of the subsurface that may contain water ice. This information could prove invaluable for future astronauts landing on Mars. Additionally, the camera can capture images of Mars' two small moons, Phobos and Deimos, allowing for the analysis of their surface compositions.
The Mars Odyssey Project is managed by NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, as a part of NASA’s broader Mars Exploration Program. Lockheed Martin Space in Denver constructed the spacecraft and collaborates with JPL on mission operations. The THEMIS camera was developed and is operated by Arizona State University in Tempe. For more information about the Odyssey mission, visit NASA's official Odyssey page.
