List of Mars orbiters

NASA's Mariner 9 reached the planet's orbit first on November 14, narrowly beating the Soviet's spacecraft amid the space race, and subsequently became the first spacecraft to orbit another planet.

2001 Mars Odyssey was launched April 7, 2001 on a Delta II rocket and currently holds the record for the longest-surviving continually active spacecraft in orbit around a planet other than Earth at 23 years, 3 months and 17 days.

On November 5, 2013, the Mars Orbiter Mission (Mangalyaan-1) was launched by the Indian Space Research Organisation (ISRO) as a "technology demonstrator" project.

Through this mission, ISRO became the first space agency to succeed in its first attempt at a Mars orbiter.

Its goals include determining how the planet's atmosphere and water, presumed to have once been substantial, were lost over time.

[14] Note that days active category does not necessarily equate to time in orbit, for example Mars Global Surveyor is expected remain in Mars orbit for 50 years after its arrival.