Curiosity, NASA’s roving geochemistry laboratory, is scheduled to land on the surface of Mars at 10:31 p.m. PDT. At the same moment, the Mars satellite known as Odyssey will pass overhead.
Because the Earth will have “set” below the Mars horizon prior to landing, the only way that messages from Curiosity indicating that it is safe can be relayed immediately to scientists on Earth is if Odyssey can act as a relay system.
Odyssey is more than 10 years old; it entered into orbit around Mars in the fall of 2001. What’s more, it is operating without a key part -– an angled wheel that allows scientists to precisely orient the satellite.
Odyssey Satellite orbiting Mars