NASA Administrator Jim Bridenstine tweeted his best wishes to China:With today’s launch, China is on its way to join the community of international scientific explorers at Mars. — Jim Bridenstine (@JimBridenstine) July 23, 2020The flight comes on the heels of the successful launch of a United Arab Emirates Mars orbiter, called Hope, from Japan on Sunday. Next up will be the launch of NASA's $2.4 billion Perseverance Mars rover from Cape Canaveral on July 30. All three missions are taking advantage of a relatively short Mars launch opportunity that comes around once every 26 months when Earth and Mars are in favorable positions to permit direct flights by existing rockets. If all goes well, the 11,000-pound Tianwen-1 spacecraft will brake into orbit around Mars next February.