London: NASA engineers are satisfied that the landing of Curiosity rover on Mars happened as well as it was planned and are confident that given the opportunity again, the accuracy of landing could be improved still further.
The scientists had few days to examine data transmitted from the vehicle as it made its historic touchdown on Monday (GMT).
The analysis indicated that all events in the entry, descent and landing (EDL) sequence occurred at, or very close to, their predicted times.
Curiosity put down just 2.4km from the targeted point on the planet’s surface - the flat floor of Gale Crater, a deep depression on Mars’ equator.
Most of the data recorded by Curiosity’s onboard inertial sensors has yet to be downlinked to Earth, but even the small fraction of information that is in the possession of engineers has allowed them to reconstruct the key moments of the landing sequence.
“Right now we’ve only got about 1MB of data - that’s less than a camera phone picture,” explained Allen Chen, the EDL operations lead at NASA’s Jet Propulsion Laboratory (JPL).
“That’s the data that was sent back via [the satellites] Mars Odyssey and Mars Reconnaissance Oribter (MRO) on the landing night.
“That 1MB of data was intended to help us figure out what happened in case we failed. All the events that we saw during EDL happened within five to 10 seconds of the expectations. This was a very nominal EDL - very few surprises, everything went well,” he told BBC News.
The time from touching the top of the atmosphere to touching the surface was seven minutes and 12 seconds - very close to a round “seven minutes of terror”, which was the phrase used to describe the difficulties of EDL.
Curiosity’s protective capsule entered the top of the atmosphere moving at Mach 24 (24 times the speed of sound), and took 3.5 minutes to slow to Mach 2 and get ready to deploy its parachute.
Most of the energy of entry was dissipated in the form of heat as the front shield pushed up against the Martian air.
The rover is now on the surface but is not expected to start moving until September.