For two decades, the longest-living spacecraft on the Red Planet has helped locate water ice, assess landing sites, and study the planet’s mysterious moons.
NASA’s 2001 Mars Odyssey spacecraft was launched 20 years ago on April 7, making it the oldest spacecraft still operating on the Red Planet. The orbiter, which takes its name from Arthur C. Clarke’s classic sci-fi novel “2001: A Space Odyssey” (Clarke blessed its use before launch), was sent to map the composition of the surface of Mars and provide a window into the past. so scientists could find out how the planet evolved.
But it has done much more than that, by uncovering trumps of water ice, which serve as a vital communication link for other spacecraft and help pave the way not only for safer landings but also for future astronauts.
Here’s a partial list of Odyssey’s many achievements.
Mapping Mars ice
Odyssey’s two decades of data have been a boon to researchers trying to determine where water ice is trapped on the planet. Understanding the water cycle on Mars – a planet that was once much wetter, like Earth – provides insight into how it has changed over time: How does water move around the planet today? Does the planet’s tilt affect where ice is stable? Odyssey’s discoveries helped resolve those questions.
“Before Odyssey, we didn’t know where this water was stored on the planet,” said project scientist Jeffrey Plaut of NASA’s Jet Propulsion Laboratory in Southern California, which leads the Odyssey mission. “We first detected it from space and later confirmed it was there using the Phoenix lander.”
Supplies of water ice are also needed to help astronauts survive on Mars and fuel their spacecraft. (In fact, astronauts were the focus of an instrument on board Odyssey that measured how much space radiation they would have to endure before it stopped operating in 2003.) The orbiter finds the water ice using its gamma ray spectrometer (GRS) detector, which has proven to be a skilled hunter on near-surface hydrogen – a proxy for water ice. The GRS measures the number of different elements on the surface of Mars and also serves as a node in NASA’s interplanetary gamma-ray burst (GRB) detection network, which identifies GRB source locations for subsequent astronomical observations.
What Mars is made of
Check out almost any map study of the surface of Mars, and it likely contains Odyssey data. For years, the most complete world maps of Mars were created using Odyssey’s infrared camera, the Thermal Emission Imaging System or THEMIS. The camera measures the surface temperature day and night, so scientists can determine which physical materials, such as stone, sand or dust, exist. The data reveals the presence of these materials based on how they heat up or cool down over the course of a Martian day.
Mapping the net effect of two decades of all that? Scientists have not only used the data to map valley networks and craters, they have also been able to discover sandstone, iron-rich rocks, salts and more – findings that provide a deeper insight into the story of Mars. “It’s hard to exaggerate how THEMIS’s world map has filled gaps in our knowledge,” said Laura Kerber of JPL, Odyssey’s deputy project scientist.
Safer landings
THEMIS has sent back more than 1 million images since it began orbiting Mars. The images and maps it created highlight the presence of hazards such as topographic features and boulders, but they also help ensure the safety of future astronauts by showing the location of sources such as water ice. This will help the scientific community of Mars and NASA decide where to go landers and rovers, including the Perseverance rover, which landed on February 18, 2021.
Routine calls home
From its inception, Odyssey has served as a long-range call center for NASA rovers and landers, returning their data to Earth as part of the Mars Relay Network. The idea of Mars relay dates back to the 1970s, when the two Viking landers sent scientific data and images back to Earth through an orbiter. An orbiter can carry radios or antennas capable of returning more data than a spacecraft on the surface. But Odyssey made the process routine when it began transferring data to and from NASA’s Spirit and Opportunity rovers.
“When the twin rovers landed, the success of transmitting data using the UHF frequency was a game changer,” said JPL’s Chris Potts, Odyssey’s mission manager.
Every day, the robbers could go elsewhere and send new images back to Earth. Through a relay like Odyssey, scientists were previously getting more data, while the public was getting more Mars images to rave about. Odyssey has supported more than 18,000 relay races. Today it shares the communication task with NASA’s Mars Reconnaissance Orbiter and MAVEN, along with the ESA (European Space Agency) Trace Gas Orbiter.
Candy-colored mane
Odyssey has studied the surface of Mars so thoroughly that scientists have turned its THEMIS camera to capture unique images of Mars’ moons Phobos and Deimos. As with the surface of Mars, studying the thermophysics of each moon helps scientists determine the properties of materials on their surface. Such information can provide a glimpse in their past: it is unclear whether the moons were caught as asteroids or chunks from Mars, blown off the surface by an ancient impact.
Future missions, such as the Japanese Space Agency’s Martian Moons eXploration (MMX) spacecraft, will attempt to land on these moons. In the distant future, missions could even create bases for astronauts on it. And when they do, they rely on data from an orbiter that began its odyssey at the turn of the millennium.
THEMIS was built and administered by Arizona State University in Tempe. Odyssey’s gamma ray spectrometer was provided by the University of Arizona, Tucson, Los Alamos National Laboratory and the Russian Space Research Institute. The Odyssey project’s prime contractor, Lockheed Martin Space in Denver, developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and JPL, a division of Caltech in Pasadena.
For more about Odyssey, visit:
https://mars.nasa.gov/odyssey/
https://www.nasa.gov/mission_pages/odyssey/index.html
News Media Contacts
Andrew Good
Jet Propulsion Laboratory, Pasadena, California.
818-393-2433
[email protected]