Seven months after blast-off, NASA's Mars 2020 mission will have to negotiate its shortest and most intense phase on Thursday: the "seven minutes of terror" it takes to slam the brakes and land the Perseverance rover on a narrow target on the planet's surface.

Entry, Descent, and Landing (EDL) begins when the spacecraft carrying Perseverance strikes the Martian atmosphere at nearly 12,500 miles per hour (20,000 kilometers per hour).

It ends around seven minutes later with the rover at rest on the surface.

Touchdown on the Jezero Crater is scheduled for 3:55 pm US eastern time (2055 GMT). Weather conditions so far appear favorable in the Martian northern hemisphere spring, but nothing is taken for granted.

"This is one of the most difficult maneuvers that we do in this business, and almost 50 percent of the spacecraft that had been sent to the surface of Mars have failed," Matt Wallace, the mission's deputy project manager said.

A NASA rover streaked through the orange Martian sky and landed on the planet Thursday, accomplishing the riskiest step yet in an epic quest to bring back rocks that could answer whether life ever existed on Mars.

Ground controllers at the space agency's Jet Propulsion Laboratory in Pasadena, California, jumped to their feet, thrust their arms in the air and cheered in both triumph and relief on receiving confirmation that the six-wheeled Perseverance had touched down on the red planet, long a deathtrap for incoming spacecraft.