Tianwen-1, China's Mars Rover and Orbiter Mission


Water doesn’t currently exist on Mars' surface, but it used to. We know this from dramatic dry canyons and river channels seen from orbit, as well as minerals on the surface that only form in liquid water. Around 3 billion years ago, something happened to Mars’ atmosphere, and most of the liquid water evaporated. But some of it may still be underground, safely shielded from harmful solar radiation that bombards the planet’s surface. Could those ancient pockets of water contain life?

China’s Tianwen-1 Mars mission launched on 23 July 2020 amidst the added challenge of the global COVID-19 pandemic. It will, among other things, search for pockets of water using radar mounted on the rover. The European Space Agency’s Mars Express spacecraft found evidence for subsurface water using radar from orbit, but this will be the first time a rover has searched from the ground. (NASA’s Perseverance rover also has a radar instrument; it will launch and land on Mars at about the same time as Tianwen-1.)

Tianwen-1 will give China valuable Mars experience and lay groundwork for a possible sample return mission planned for the end of the 2020s. Getting Martian samples back to Earth is a top priority for the scientific community. Despite the impressive advances made in placing miniature science instruments on spacecraft, only Earth-bound technology can date samples with absolute precision, reproduce scientific results, and verify the presence or absence of life in a sample.

Only NASA has successfully landed and operated spacecraft on Mars. More countries exploring Mars and our solar system means more discoveries and opportunities for global collaboration. Space exploration brings out the best in us all, and when nations work

together everyone wins.

Tianwen means "questions to heaven," or "questioning the heavens." You can listen to a pronunciation of Tianwen by Quanzhi Ye. All interplanetary Chinese missions are expected to carry the Tianwen moniker going forward.


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Water doesn’t currently exist on Mars' surface, but it used to. We know this from dramatic dry canyons and river channels seen from orbit, as well as minerals on the surface that only form in liquid water. Around 3 billion years ago, something happened to Mars’ atmosphere, and most of the liquid water evaporated. But some of it may still be underground, safely shielded from harmful solar radiation that bombards the planet’s surface. Could those ancient pockets of water contain life?

China’s Tianwen-1 Mars mission launched on 23 July 2020 amidst the added challenge of the global COVID-19 pandemic. It will, among other things, search for pockets of water using radar mounted on the rover. The European Space Agency’s Mars Express spacecraft found evidence for subsurface water using radar from orbit, but this will be the first time a rover has searched from the ground. (NASA’s Perseverance rover also has a radar instrument; it will launch and land on Mars at about the same time as Tianwen-1.)

Tianwen-1 will give China valuable Mars experience and lay groundwork for a possible sample return mission planned for the end of the 2020s. Getting Martian samples back to Earth is a top priority for the scientific community. Despite the impressive advances made in placing miniature science instruments on spacecraft, only Earth-bound technology can date samples with absolute precision, reproduce scientific results, and verify the presence or absence of life in a sample.

Only NASA has successfully landed and operated spacecraft on Mars. More countries exploring Mars and our solar system means more discoveries and opportunities for global collaboration. Space exploration brings out the best in us all, and when nations work

together everyone wins.

Tianwen means "questions to heaven," or "questioning the heavens." You can listen to a pronunciation of Tianwen by Quanzhi Ye. All interplanetary Chinese missions are expected to carry the Tianwen moniker going forward.