The 2001 Odyssey spacecraft captured the first sight of Arsia Mons, who dwarfed the highest volcano on Earth.

A new panoramic view from NASA's 2001 Mars Odyssey Orbit shows one of the largest volcanoes on the Red Planet, Arsia Mons, poked on the pre-dawn awning. Arsia Mons and two other volcanoes form the so-called tharsis montes or Tharsis Mountains, which are usually surrounded by water ice clouds (as opposed to the same common carbon dioxide clouds on Mars), especially in the early morning. The panorama marks the first time a volcanic imaging has been performed on Earth, with the same Martian perspective as the Earth stared at by astronauts from the International Space Station.

Launched in 2001, Odyssey is the longest-running mission, releasing around another planet, and this new panorama represents the type of science in orbit that began pursuing in 2023 when it captured the first of four current high seascape images. To obtain them, the spacecraft rotated 90 degrees in orbit so that the camera used to study the surface of Mars can take images.

This angle allows scientists to see clouds of dust and water ice, while a series of images enable them to observe changes throughout the season.

“We see some very significant seasonal differences in these horizon images,” said Michael D. Smith, a planetary scientist at the Goddard Space Flight Center in Greenbelt, Maryland. “This provides us with new clues about how the Martian atmosphere develops over time.”

Understanding Mars' clouds is especially important for understanding the weather on Earth and how phenomena like dust storms occur. This information, in turn, can benefit future missions, including entry, descent and landing operations.

Although these images are concentrated on the upper atmosphere, the Odyssey team also attempts to include interesting surface features in it. In the latest horizon image of the Odyssey captured on May 2, Arsia Mons is 12 miles (20 km) tall, about twice as high as the Mauna Loa, the largest volcano on Earth, which rises to 6 miles (9 km) under the sea.

The southernmost volcano of Arsia Mons is the cloudiest of the three. Clouds form as the air blows to the side of the mountain and then cools quickly. When Mars are farthest from the Sun, they are particularly thick, which is a period called aphelion. This time of year, the entire planet's equator forms the cloud band called Aphelion Cloud Belt, which proudly displays in the new Odyssey panorama.

“We chose Arsia Mons and hopefully we can see the summit poke above the clouds in the early morning. It’s not disappointing,” said Jonathon Hill of Arizona State University, who heads operations for Odyssey cameras, called the thermal emission imaging system or themis.

Themis cameras can view Mars in visible and infrared light. The latter allows scientists to identify underground areas containing water ice, which the first astronauts can use on Mars. The camera also allows images of Mars' tiny satellites, phobos and Deimos, allowing scientists to analyze their surface composition.

NASA's Jet Propulsion Laboratory is part of the Caltech division in Pasadena, California, and is the agency's Mars Odyssey program at the Washington Bureau of Science and Education, NASA's MARS MARS Exploration Program Portfolio. The spacecraft was built by Denver’s Lockheed Martin space and worked with JPL on mission operations. Themis is built and operated by Arizona State University in Tempe.

More information about the Odyssey:

Hello Andrew
Jet Propulsion Laboratory in Pasadena, California.
818-393-2433
andrew.c.good@jpl.nasa.gov

Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

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