Kawasaki Concours Forum
Mish mash => Open Forum => Topic started by: Conrad on August 01, 2012, 10:51:54 AM
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http://science.nasa.gov/science-news/science-at-nasa/2012/30jul_skycrane/ (http://science.nasa.gov/science-news/science-at-nasa/2012/30jul_skycrane/)
July 30, 2012: On August 5th at 10:31 p.m. Pacific Time, NASA will gently deposit their new, 2000-pound Curiosity rover on the surface of Mars, wheels-first and ready to roll. Quite a feat – because it will come screaming through the Martian atmosphere at 13,000 mph.
Curiosity, aka the Mars Science Laboratory, will be the largest mission ever to land on another planet. It's big because it has a big mystery to solve: was Mars ever or is it still capable of harboring life?
During its grand entrance, the lander must slow to 1 1/2 mph to touch down safely. That kind of braking action for a one-ton payload demands the nail-bitingly precise unfolding of an intricately choreographed sequence of events. Key players: a red-hot heat shield, a huge parachute, 76 explosive bolts -- and a Sky Crane.
7 Minutes of Terror: Curiosity Rover's Risky Mars Landing | Video (http://www.youtube.com/watch?v=h2I8AoB1xgU#ws)
"The whole ballgame transpires within 7 minutes, from atmospheric entry to touch-down," says Jet Propulsion Laboratory's Steve Sell, Deputy Operations Lead for Entry, Descent, and Landing. "The onboard computer calls the shots. And if any one maneuver fails, it's game over."
Here's the game plan.
"Atmospheric friction slows the capsule containing Sky Crane -- an eight-rocket jetpack attached to the rover -- from 13000 to 1000 mph. [Mars' atmosphere is too thin to slow it more.] The friction burnishes the capsule's heat shield to a glowing 3800 degrees Fahrenheit (2100 degrees Celsius). Then a 60-foot diameter parachute deploys and inflates above the capsule on 160-foot lines. What's left of the heat shield jettisons, giving Curiosity its first look at its new home below."
This is the largest, strongest parachute ever flown to another world. It has to be a super-chute to handle the 65000 pounds of force produced when the rover snaps to attention below it.
(http://www.nasa.gov/images/content/593481main_pia14839-43_946-710.jpg)
"After the payload slows to about 200 mph, explosive bolts free the chute and Sky Crane free-falls for a second. Then its retrorockets fire."
The rockets slow the descent to 1 ½ mph and power a sideways parry to avoid the faster falling chute. As Sky Crane descends to 60 feet above Mars' surface, the rover inches down from underneath it on three nylon ropes like a spider spinning strands of its web. With Curiosity dangling 20 feet below, Sky Crane continues its downward progress until the rover is resting on the surface. Explosive bolts cut Curiosity's last physical attachments to the outside world, and Sky Crane flies away to death-plunge into the red sands, its incredible job done.
It might sound frighteningly complicated, "but what appears to be a complex system actually simplifies the landing greatly," explains Sell.
Previous missions such as Vikings I and II and the Mars Phoenix Lander used retrorockets to lower spacecraft all the way to the surface atop a legged lander. Others have used airbags. Neither method is feasible for Curiosity.
"With a payload this size, the rockets could kick up enough dust to compromise the rover and its instruments," explains Sell. "And the rockets could excavate craters Curiosity would have to avoid as it drives away. Add to that the risk of a big, heavy vehicle driving down off the lander via an exit ramp to reach the surface."
Pathfinder, Spirit, and Opportunity used airbags to eliminate these concerns. But Curiosity is too large for airbags.
"Bags big enough to soften its landing would be too heavy or too costly to launch. Besides, you'd have to drop the payload so slowly for the bags to survive the load, you may as well place the rover right on its wheels."
(http://science.nasa.gov/media/medialibrary/2012/07/30/generations.jpg)
Three generations of Mars rovers. Curiosity (pictured right) is more massive than its predecessors, which is why NASA had to develop an innovative landing system.
Sky Crane, says Sell, makes sense for Curiosity. But it still keeps him up at night.
"I leave myself voicemails in the middle of the night about things to check in the morning. We've run thousands of tests and simulations, thinking of ways to 'break' the system so we can build in comfortable performance margins. We're still testing. There's always one more test we can run. We're always afraid we missed something."
In the control room at JPL the night of August 5th, it will be too late. It takes 14 minutes for signals to travel from Mars to Earth. When the team receives the signal 'I am entering the atmosphere,' Curiosity will be alive or dead on the surface.
Says Sell: "I'm already holding my breath."
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http://science.nasa.gov/science-news/science-at-nasa/2012/30jul_skycrane/ (http://science.nasa.gov/science-news/science-at-nasa/2012/30jul_skycrane/)
July 30, 2012: On August 5th at 10:31 p.m. Pacific Time, NASA will gently deposit their new, 2000-pound Curiosity rover on the surface of Mars, wheels-first and ready to roll. Quite a feat – because it will come screaming through the Martian atmosphere at 13,000 mph.
No good can come from this, methinks. In the old days, we used balloons. Darn new fangled Mars rovers, hogwash!
Hopefully we'll be able to know when it hits the surface. Should be a big puff of dust, large enough to see via telescope I would think. In looking at the animation and all the parts that have to work and wondering how the heck they tested this, I don't think it has a snowball's chance to survive. I'm crossing my fingers, though.
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That's the thing Jim. By lowering the lander to the surface with the sky crane, there shouldn't be any dust clouds.
Check it out on the Science Channel, they're running a special all about it.
http://science.discovery.com/tv-schedules/special.html?paid=48.15727.137576.43765.0 (http://science.discovery.com/tv-schedules/special.html?paid=48.15727.137576.43765.0)
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Check it out on the Science Channel, they're running a special all about it.
Wish I could, but Comcast took the SCI out of my lineup. :banghead:
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With the atmosphere so thin I would expect the dust to settle pretty quickly like on the moon. Also I remember watching some of the lift offs on the moon from the lunar rovers and don't remember any dust clouds. Why is it more of a problem on mars?
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With the atmosphere so thin I would expect the dust to settle pretty quickly like on the moon. Also I remember watching some of the lift offs on the moon from the lunar rovers and don't remember any dust clouds. Why is it more of a problem on mars?
Dunno. Maybe since the lander plus the sky crane weigh so much that there's a LOT more thrust needed?
Did you watch the video? They talked about that and the rover can't have any dust on it.
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Dunno. Maybe since the lander plus the sky crane weigh so much that there's a LOT more thrust needed?
Did you watch the video? They talked about that and the rover can't have any dust on it.
Sounds logical. Also maybe even the very thin atmosphere is enough to make a difference.
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I want to know who will be there filming the live coverage of the landing? Marvin?
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I want to know who will be there filming the live coverage of the landing? Marvin?
(http://epguides.com/DuckDodgers/cast.jpg)
I think that it's the duck's turn this time. What's going on with Porky anyway? Not that there's anything wrong with that... At least he'd got some pants on this time.
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Actually, the puff of dust will be the lander hitting at 13000 mph. What's the pool up to that it won't survive?
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Actually, the puff of dust will be the lander hitting at 13000 mph. What's the pool up to that it won't survive?
Last I checked the bookies are giving 20-1 odds that one bolt will not explode sending the rig into the planet at a extreme high rate of speed.
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Actually, the puff of dust will be the lander hitting at 13000 mph. What's the pool up to that it won't survive?
That will be the most expensive crater ever! $2.5 billion.
(http://25.media.tumblr.com/tumblr_ktzgwtFv4W1qa9armo1_500.jpg)
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Great video, thanks.
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The engineers at JPL are pretty bright. I think its going to be successful. Once the heat shield is off maybe they can get video of the decent and landing. I'd love to see that.
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I agree Rhino. I think that it's going to work and that it's going to be amazing.
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Who will be there to shoot the video from the planet surface?
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Who will be there to shoot the video from the planet surface?
That's the second time that you've asked that. What are you talking about exactly?
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The moon landing was a fake too.
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The moon landing was a fake too.
They lied to us? NO way! ;)
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Who will be there to shoot the video from the planet surface?
Are you referring to my post regarding wanting to see a video of the descent? I was just wondering if a camera on Curiosity itself might be active while it is descending, after heat shield separation and if so we could eventually see the POV landing of Curiosity. Even if it is looking at the horizon or just up at the sky crane it would be very interesting.
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I would hope that the sky crane will have cameras too. We could see the landing from two points of view.
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This is some really cool stuff. It's right out of sci fi movie. I hope it gets down without a hitch.
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What's going on with Porky anyway? Not that there's anything wrong with that... At least he'd got some pants on this time.
Porky's gone ATGATT !!
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Curiosity Has Landed! Can I get a woot! woot!
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The life of a rover is rough
(http://imgs.xkcd.com/comics/spirit.png)
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Curiosity Has Landed! Can I get a woot! woot!
Woot!!!! Woot!!!!
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WOOT!!!! WOOT!!!!
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Absolutely awesome!
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It's a good thing these guys are rocket scientists. This was an unfathomably difficult task!
:thumbs: :thumbs: :thumbs:
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I'll be the lone voice of dissension. It is an unfathomable waste of money, especially for a country who has more debt than the entirety of it's citizens earn in an entire year.
The only greater waste of money would have been to send a manned mission.
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Come on, we need a forward launching base for when the Klingon\Borg\Cylons come to attack.
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I'll be the lone voice of dissension. It is an unfathomable waste of money, especially for a country who has more debt than the entirety of it's citizens earn in an entire year.
The only greater waste of money would have been to send a manned mission.
:goodpost:
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Come on, we need a forward launching base for when the Klingon\Borg\Cylons come to attack.
And the Tribbles, don't forget about them!
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And the Tribbles, don't forget about them!
That sounds like trouble!
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That sounds like trouble!
Trouble with Tribbles; never.........
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http://science.nasa.gov/science-news/science-at-nasa/2012/06aug_parachute/ (http://science.nasa.gov/science-news/science-at-nasa/2012/06aug_parachute/)
NASA's Curiosity Rover Caught in the Act of Landing August 6, 2012: An image from the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance orbiter captured the Curiosity rover still connected to its 51-foot-wide (almost 16 meter) parachute as it descended towards its landing site at Gale Crater.
(http://www.nasa.gov/images/content/673734main_PIA15978-43_516-387.jpg)
Curiosity and its parachute are in the center of the white box; the inset image is a cutout of the rover stretched to avoid saturation. Image credit: NASA/JPL-Caltech/Univ. of Arizona
"If HiRISE took the image one second before or one second after, we probably would be looking at an empty Martian landscape," said Sarah Milkovich, HiRISE investigation scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "When you consider that we have been working on this sequence since March and had to upload commands to the spacecraft about 72 hours prior to the image being taken, you begin to realize how challenging this picture was to obtain."
The image was taken while MRO was 211 miles (340 kilometers) away from the parachuting rover. Curiosity and its rocket-propelled backpack, contained within the conical-shaped back shell, had yet to be deployed. At the time, Curiosity was about two miles (three kilometers) above the Martian surface.
"Guess you could consider us the closest thing to paparazzi on Mars," said Milkovich. "We definitely caught NASA's newest celebrity in the act."
Curiosity, NASA's latest contribution to the Martian landscape, landed at 10:32 p.m. Aug. 5, PDT, (1:32 on Aug. 6, EDT) near the foot of a mountain three miles tall inside Gale Crater, 96 miles in diameter.
(http://www.nasa.gov/images/content/673745main_pia15981-43_946-710.jpg)
The green diamond shows approximately where NASA's Curiosity rover landed on Mars, a region about 2 kilometers northeast of its target in the center of the estimated landing region (blue ellipse)
In other Curiosity news, one part of the rover team at the JPL continues to analyze the data from last night's landing while another continues to prepare the one-ton mobile laboratory for its future explorations of Gale Crater. One key assignment given to Curiosity for its first full day on Mars is to raise its high-gain antenna. Using this antenna will increase the data rate at which the rover can communicate directly with Earth. The mission will use relays to orbiters as the primary method for sending data home, because that method is much more energy-efficient for the rover.
More images are coming. To find out what to expect, click here ==> http://www.nasa.gov/mission_pages/msl/news/msl20120803.html (http://www.nasa.gov/mission_pages/msl/news/msl20120803.html)
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Fake !
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I knew it would land safely.... ::) . Actually, it's good to know that NASA still has engineers with the same smarts as those that put us on the Moon.
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I read a blog today where the author of one entry lamented the fact that there was not sound coming back with the pictures from Mars. He speculated that maybe it was harder to send sound data than video data. Understanding science thingies -- it really is important.
Having grown up with the low-resolution, grainy photos of early space mission, I am astounded at the quality of what is coming back from Curiosity.
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I read a blog today where the author of one entry lamented the fact that there was not sound coming back with the pictures from Mars. He speculated that maybe it was harder to send sound data than video data. Understanding science thingies -- it really is important.
Having grown up with the low-resolution, grainy photos of early space mission, I am astounded at the quality of what is coming back from Curiosity.
The atmosphere on Mars is 1/100 what it is on Earth. Not sure how much sound there is and how useful it would be. Any sound they might pic up would be some wind perhaps and the sound of the equipment on the rover itself.
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I read a blog today where the author of one entry lamented the fact that there was not sound coming back with the pictures from Mars. He speculated that maybe it was harder to send sound data than video data. Understanding science thingies -- it really is important.
Having grown up with the low-resolution, grainy photos of early space mission, I am astounded at the quality of what is coming back from Curiosity.
:rotflmao:
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If they had sound we might be able to hear the Martians skipping around the rover's camera's.
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There was some video of the descent. Looks like there was some dust kicked up after all.
Curiosity's Descent (http://www.youtube.com/watch?v=UcGMDXy-Y1I#ws)
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We get to Mars, and already we're shooting things with lasers. (http://news.yahoo.com/pew-pew-pew-nasas-curiosity-rover-zaps-mars-051410654.html)
Yay, Second Amendment! :shoot:
:rotflmao:
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:rotflmao:
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7 of 9's phaser is set to...stunning. :P
(http://static.fameball.com/imgcache/17/65/0)
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7 of 9's phaser is set to...stunning. :P
(http://static.fameball.com/imgcache/17/65/0)
Resistance is futile :P
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Resistance is futile :P
Who's resisting?!
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Making tracks
http://lightyears.blogs.cnn.com/2012/08/22/mars-rover-passes-first-driving-test/?hpt=hp_t1 (http://lightyears.blogs.cnn.com/2012/08/22/mars-rover-passes-first-driving-test/?hpt=hp_t1)
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He didn'tuild that :-X