China's first Mars probe has beamed back a photo of the Earth and the Moon as it heads toward its destination, the country's space agency said Tuesday.

The image, which shows the two celestial bodies as small crescents in the empty darkness of space, was taken 1.2 million kilometres (746,000 miles) away from Earth three days after the Tianwen-1 mission was launched on Thursday, the China National Space Administration said.

China joined the United States and United Arab Emirates this month in launching a mission to Mars, taking advantage of a period when Mars and Earth are favourably aligned.

The mission, given a name that means "Questions to Heaven," aims to enter Martian orbit seven months after the launch and release a small rover to study the planet's surface.

It's the latest milestone in Beijing's space programme, which has sent two rovers to the Moon and set up a satellite navigation, Beidou, to rival the United States' GPS.

The National Space Administration on Tuesday said Tianwen-1, which has left Earth's gravitational field, "is currently in good flight conditions, has balanced fuel and is operating normally."

The rover had by Tuesday traveled least 1.5 million kilometres from Earth, the agency said -- just a fraction of the 55 million kilometres it must traverse before it reaches Mars.