NASA’s Mars Odyssey spacecraft launched 20 years in the past on April 7, making it the oldest spacecraft nonetheless working on the Crimson Planet. The orbiter, which takes its identify from Arthur C. Clarke’s basic sci-fi novel “2001: A Area Odyssey” (Clarke blessed its use earlier than launch), was despatched to map the composition of the Martian floor, offering a window to the previous so scientists may piece collectively how the planet advanced, acts as orbiting communications hyperlink for different spacecraft, and helps to search out secure touchdown websites for different Mars missions.
“Earlier than Odyssey, we did not know the place water was saved on the planet,” mentioned Venture Scientist Jeffrey Plaut of NASA’s Jet Propulsion Laboratory in Southern California, which leads the Odyssey mission. “We detected it for the primary time from orbit and later confirmed it was there utilizing the Phoenix lander.” Aside answering some geological questions, the invention of water ice is required to assist future astronauts survive on Mars and to offer gas for his or her spacecraft. The feasibility of people touring to Mars was additionally the main focus of an instrument aboard Odyssey that measured how a lot area radiation astronauts must cope with earlier than it stopped working in 2003.
The orbiter finds the water ice utilizing its gamma-ray spectrometer (GRS) detector, which measures near-surface hydrogen—a proxy for water ice. The GRS measures the quantity of various parts on the Martian floor and in addition serves as a node in NASA’s interplanetary gamma-ray burst (GRB) detection community, which identifies supply areas of GRB’s for follow-up astronomical observations.
For a few years, probably the most full international maps of Mars had been made utilizing Odyssey’s infrared digital camera, known as the Thermal Emission Imaging System, or THEMIS. The digital camera measures the floor temperature day and night time, permitting scientists to find out what bodily supplies, corresponding to rock, sand, or mud, exist. Its knowledge reveals the presence of those supplies primarily based on how they warmth up or quiet down over the course of a Martian day.
Due to THEMIS knowledge scientists not solely mapped the Martian terrain, they’ve additionally been capable of spot sandstone, iron-rich rocks, salts, and extra—findings that assist lend deeper perception to Mars’ geological historical past.
THEMIS has despatched again greater than 1 million photographs because it started circling Mars. The photographs and maps it is produced spotlight the presence of hazards, corresponding to topographic options and boulders, however in addition they assist guarantee the protection of future astronauts by exhibiting the placement of sources corresponding to water ice. This aids the Mars science neighborhood and NASA in deciding the place to ship landers and rovers—together with the Perseverance rover, which touched down on February 18, 2021.
From early on, Odyssey has served as a long-distance name heart for NASA’s rovers and landers, sending their knowledge again to Earth as a part of the Mars Relay Community. The concept goes again to the 1970’s, when the 2 Viking landers despatched science knowledge and pictures by short-range radio frequencies to the orbiter, who relayed the info again to Earth. An orbiter can carry radios or antennas able to sending again extra knowledge than a floor spacecraft. However Odyssey made the method routine when it started conveying knowledge to and from NASA’s Spirit (lively 2004-2010) and Alternative (2004-2018) rovers.
Odyssey has supported over 18,000 relay classes. Today, it shares the communications process with NASA’s Mars Reconnaissance and MAVEN Orbiter, together with the ESA (European Area Company) Hint Fuel Orbiter.
Odyssey has carried out such an intensive job of learning the Martian floor that scientists have began turning its THEMIS digital camera to seize distinctive views of Mars’ moons Phobos and Deimos. As with the Martian floor, learning every moon’s thermophysics helps scientists decide the properties of supplies on their surfaces. Such info can supply glimpses into their previous: It is unclear whether or not the moons are captured asteroids or chunks of Mars, blasted off the floor by an historical influence.