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- 1.4 August 2012 Last updated at 22:13 GMTShare this page Email Print2.2K Share Facebook TwitterNasas Curiosity rover edges closer to MarsBy Jonathan Amos Science correspondent, BBC News, Pasadena Communications from the rover during descentwill come to the Jet Propulsion LaboratoryContinue reading the main storyRelated Stories Gale Crater: Geological sweet shop Mars success depends on crazy landing Rover on course for Mars landingNasas Curiosity rover is on course to land on Mars on Monday, where it will search for clues inthe Red Planets rocks and soil about whether it could once have supported life.The robots flight trajectory is so good engineers cancelled the latest course correction they hadplanned.To land in the right place, it must hit a box at the top of the atmosphere that measures just 3kmby 12km.
2. Curiosity has spent eight months travelling from Earth to Mars.The robot - -also known as the Mars Science Laboratory - has covered more than 560 millionkm."Our inbound trajectory is right down the pipe," said Arthur Amador, Curiositys missionmanager."The team is confident and thrilled to finally be arriving at Mars, and were reminding ourselvesto breathe every so often. Were ready to go."The rovers power and communications systems are in excellent shape.The one major task left for the mission team is to prime the back-up computer that will takecommand if the main unit fails during the entry, descent and landing (EDL) manoeuvres.Continue reading the main storyCuriosity - Mars Science Laboratory Mission goal is to determine whether Mars has ever had the conditions to support life Project costed at $2.5bn; will see initial surface operations lasting two Earth years Onboard plutonium generators will deliver heat and electricity for at least 14 years 75kg science payload more than 10 times as massive as those of earlier US Mars rovers Equipped with tools to brush and drill into rocks, to scoop up, sort and sieve samples Variety of analytical techniques to discern chemistry in rocks, soil and atmosphere Will try to make first definitive identification of organic (carbon-rich) compounds Even carries a laser to zap rocks; beam will identify atomic elements in rocks Gale Crater: Geological sweet shop Discover more about the planets 3. The robot was approaching Mars at about 13,000km/h on Saturday. By the time the spacecrafthits the top of Mars atmosphere, about seven minutes before touch-down, gravity will haveaccelerated it to about 21,000km/h.The vehicle is being aimed at Gale Crater, a deep depression just south of the planets equator.It is equipped with the most sophisticated science payload ever sent to another world.Its mission, when it gets on the ground, is to characterise the geology in Gale and examine itsrocks for signs that ancient environments on Mars could have supported microbial life.Touch-down is expected at 05:31 GMT (06:31 BST) Monday 6 August; 22:31 PDT, Sunday 5August.It is a fully automated procedure. Nasa will be following the descent here at mission control atthe Jet Propulsion Laboratory in Pasadena, California.The rover will broadcast X-band and UHF signals on its way down to the surface.These will be picked up by a mix of satellites at Mars and radio antennas on Earth.The key communication route will be through the Odyssey orbiter. It alone will see the rover allthe way to the ground and have the ability to relay UHF telemetry straight to Earth.And mission team members remain hopeful that this data will also include some images thatCuriosity plans to take of itself just minutes after touching the ground.These would be low-resolution, wide-angle, black and white images of the rear wheels.They may not be great to look at, but the pictures will give engineers important informationabout the exact nature of the terrain under the rover.A lot has been made of the difficulty of getting to Mars, and historically there have been farmore failures than successes (24 versus 15), but the Americans recent record at the Red Planet isactually very good - six successful landings versus two failures.Even so, Nasa continues to downplay expectations."If were not successful, were going to learn," said Doug McCuistion, the head of the US spaceagencys Mars programme."Weve learned in the past, weve recovered from it. Well pick ourselves up, well dust ourselvesoff, well do something again; this will not be the end."The human spirit gets driven by these kinds of challenges, and these are challenges that drive usto explore our surroundings and understand whats out there." 4. Curiosity is heading for Gale CraterThe mission team warned reporters on Saturday not to jump to conclusions if there was noimmediate confirmation of landing through Odyssey.There were "credible reasons", engineers said, why the UHF signal to Odyssey could be lostduring the descent, such as a failure on the satellite or a failure of the transmitter on the rover.Continued efforts would be made to contact Curiosity in subsequent hours as satellites passedoverhead and when Gale Crater came into view of radio antennas on Earth."There are situations that might come up where we will not get communications all the waythrough [to the surface], and it doesnt necessarily mean that something bad has happened; it justmeans well have to wait and hear from the vehicle later," explained Richard Cook, the deputyproject manager.This was emphasised by Allen Chen, the EDL operations lead. His is the voice from missioncontrol that will be broadcast to the world during the descent. He will call out specific milestoneson the way down. He told BBC News there would be no rush to judgement if the Odyssey linkwas interrupted or contained information that was "off nominal"."I think we proceed under any situation as though the spacecraft is there, and there for us torecover - to find out what happened," he said."Thats the most sensible thing to do. There are only a few instances I think where you couldknow pretty quickly that wed be in trouble."Step by step: How the Curiosity rover will land on MarsContinue reading the main story 5. As the rover, tuckedinside its protective capsule, heads to Mars, it dumps the disc-shaped cruise stage that hasshepherded it from Earth.5 August 2012 Last updated at 21:42 GMTShare this page Email Print3.1K Share Facebook TwitterNasas Curiosity Mars rover set for high risklandingComments (143)By Jonathan Amos Science correspondent, BBC News, Pasadena 6. Nasa news conference after the Curiosity rover lands on MarsContinue reading the main storyRelated Stories Rover edges closer to Red Planet Gale Crater: Geological sweet shop awaits Mars rover Mars success depends on crazy landingOne of the most daring space missions ever undertaken is nearing Mars.Nasa will attempt to land its one-tonne Curiosity rover on the Red Planet to study the possibilitythat this world may once have hosted microbial life.The vehicle is packed with scientific instruments, including a laser that can zap rocks todetermine their make-up.Curiosity is currently hurtling through space, close to the end of a 570 million km journey fromEarth.Engineers describe its trajectory as near-perfect and they have passed up the last twoopportunities to make course corrections.The rover, tucked inside a protective shell, is due to begin its descent to the surface at 05:24GMT, Monday (06:24 BST; 22:24 PDT, Sun).A signal confirming it has landed inside a deep depression known as Gale Crater is expected onEarth about seven minutes later, at 05:31 GMT.But getting this audacious exploration project safely down will be a colossal challenge. 7. Two-thirds of all missions sent to the Red Planet have failed, a good many lost on entry into thethin but unforgiving Martian atmosphere.Continue reading the main storyCuriosity - Mars Science LaboratoryMission goal is to determine whether Mars has ever had the conditions to support lifeProject costed at $2.5bn; will see initial surface operations lasting two Earth yearsOnboard plutonium generators will deliver heat and electricity for at least 14 years75kg science payload more than 10 times as massive as those of earlier US Mars roversEquipped with tools to brush and drill into rocks, to scoop up, sort and sieve samplesVariety of analytical techniques to discern chemistry in rocks, soil and atmosphereWill try to make first definitive identification of organic (carbon rich) compoundsEven carries a laser to zap rocks; beam will identify atomic elements in rocksDiscover more about the planetsAnd yet, the US space agency has high confidence that the high-risk descent strategy itsengineers have devised will deliver an intact vehicle to the surface.This strategy will use a sequence of fully automated manoeuvres to slow the fall from an initial20,000km/h at the top of the atmosphere to less than 1m/s at the moment of touch-down.The last stage in the sequence will see a hovering, rocket-powered crane lower the rover to theground on nylon cords.The manoeuvres have raised eyebrows because of their complexity, but the entry, descent andlanding (EDL) team leader, Adam Steltzner, has emphasised the amount of "reasonedengineering" that has informed the design."I slept better last night than I have in years, and I think thats because its done - whateversgoing to happen is going to happen," he said. 8. Nasa will be monitoring the drama from the Jet Propulsion Laboratory (JPL) in Pasadena,California.It is here that mission control will receive the telemetry from Curiosity that has been bounced toEarth by the overflying satellite known as Odyssey.Engineers can only watch and wait, however. The 250 million km between Mars and Earth rightnow means there is a 13-minute lag in communications.The mission team knows that when it gets that first signal to say the rover has entered theplanets atmosphere, the vehicle will in reality have already landed or been destroyed some sevenminutes previously.Step by step: How the Curiosity rover will land on MarsCon