It has been 10 years since Elon Musk's SpaceX launched the commercial space age. What hurdles must be overcome before private companies begin exploring, colonizing and mining other planets?
If humans are to live on Mars they will need a stable supply of food. Earth plants are not suited to the Mars climate but we can engineer plants that are.
Space exploration is exciting - but there are barriers for humans hoping to visit and even stay on planets. Buried ice on Mars could be a water source for interplanetary visits of the future.
Working out how Mars's carbon dioxide was turned into rock could help with carbon capture efforts on our own planet.
NASA has set a target date of 2030 for a manned mission to Mars. With no real scientific breakthroughs needed, success depends on developing the proper technology.
New research suggests that salty water exists on Mars in the summer months. But that wouldn't be the first time we hear of water on the red planet. So what's new and what isn't?