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NASA Phoenix Mission Ready For Mars Landing

kdawson posted more than 6 years ago | from the boulder-dodging dept.

Mars 101

Several readers relayed the press release from JPL about the upcoming landing of NASA's Phoenix Mars Lander on May 25. It's going to set down in the north polar regions and look for indications of whether conditions have ever been favorable for microbial life. "Phoenix will enter the top of the Martian atmosphere at almost 21,000 kilometers per hour... In seven minutes, the spacecraft must complete a challenging sequence of events to slow to about 8 kilometers per hour... before its three legs reach the ground. Confirmation of the landing could come as early as 7:53 p.m. EDT. 'This is not a trip to grandma's house. Putting a spacecraft safely on Mars is hard and risky,' said Ed Weiler, associate administrator for NASA's Science Mission Directorate. 'Internationally, fewer than half the attempts have succeeded.'"

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Great stuff I guess but why isn't NASA doing more? (0, Insightful)

Anonymous Coward | more than 6 years ago | (#23400482)

Is it just me, or is this just not really the right stuff anymore?

It just seems like a way to earn a good salary and have a lot of fun!

Re:Great stuff I guess but why isn't NASA doing mo (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#23400532)

wooh, my first fp

Re:Great stuff I guess but why isn't NASA doing mo (1, Offtopic)

mrbluze (1034940) | more than 6 years ago | (#23400542)

wooh, my first fp
And you wasted it by posting something sensible! Sheeesh!

Re:Great stuff I guess but why isn't NASA doing mo (-1, Troll)

pipatron (966506) | more than 6 years ago | (#23400696)

You just missed your chance to join the GNAA.

Re:Great stuff I guess but why isn't NASA doing mo (-1, Offtopic)

Faylone (880739) | more than 6 years ago | (#23400726)

That's like saying you just missed your chance to to drink sulfuric acid.

Re:Great stuff I guess but why isn't NASA doing mo (1)

CDMA_Demo (841347) | more than 6 years ago | (#23400780)

From TFA:

three-month mission to taste and sniff fistfuls of Martian soil and buried ice
What is this, some sort of sick joke? (Haven't these NASA writers discovered internet spam yet?)

Re:Great stuff I guess but why isn't NASA doing mo (1)

Cally (10873) | more than 6 years ago | (#23409268)

No, the problem is that some bloody moron instructed them to spend all their money on a white elephant manned mission to the moon. ISS at least keeps the Russians and Euroweenies happy; manned flight out of LEO is a dead end, though, and unfortunately the Mars and outer planet budgets have been gutted to pay for it. Did you know that several of the biannual launch slots for Mars vehicles are going to be empty over the next decade? MSL (a little bit) and lunar pie-in-the-sky (mostly) are to blame.

Don't say I didn't tell you so. Enjoy the MERs while you still got 'em (you do check what they're up to every now and then, right?) and keep your fingers crossed for Phoenix at 00:30 UTC on the 26th. (Personally I will be glued to NASA TV and crapping myself at that point. Not a good combo.)

Re:Great stuff I guess but why isn't NASA doing mo (1)

aliquis (678370) | more than 6 years ago | (#23415734)

The funny part with all Bush bashing is that it do make me wonder what kind of people would vote for a moron as president ;)

But then I guess most partys and leaders and such gets their share of bashing no matter who they are, and Bush may be a moron extraordinaire so I guess it's appropriate and understandable.

Re:Great stuff I guess but why isn't NASA doing mo (1)

aliquis (678370) | more than 6 years ago | (#23415750)

You use abbreviations way to much, I started with looking up LEO:
LEO - Low Earth Orbit

But then I found MSL, "lunar pie-in-the-sky" and MER.

What does it all mean?

IANAAS.

Good article and GREAT PICTURES of the Phoenix (5, Informative)

blind biker (1066130) | more than 6 years ago | (#23400498)

I am sure a lot of slashdot readers are interested (I know I was) in how does this beast actually look like. So here's a very good article on the Phoenix lander with a couple of fantastic artistic concepts [scitech.ac.uk] based on the actual Phoenix.

Re:Good article and GREAT PICTURES of the Phoenix (1)

Thanshin (1188877) | more than 6 years ago | (#23400670)

here's a very good article on the Phoenix lander with a couple of fantastic artistic concepts based on the actual Phoenix.
The bird? The city? The A-Team member?

Oh, I thought you said ... (-1, Offtopic)

Rotund Prickpull (818980) | more than 6 years ago | (#23401220)

                    _ooo_
                 o-'     '-o
                /     _    _v
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      i i  i  i i  i        /        ,--ooooooooo,
      ii i  i  i  i/       i       o'           -e'o
      i i  i  i i /       /       ov               '
      i  i   i  /`      ov   _,ee"  v             o'
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    ~ooee`     vv   i`i / /ee"`
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    ~ ~~         _')")
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Re:Good article and GREAT PICTURES of the Phoenix (1)

somersault (912633) | more than 6 years ago | (#23402920)

Wow, the latest members don't even read the summary titles, and only read every second word in the comments! Very efficient

Re:Good article and GREAT PICTURES of the Phoenix (4, Funny)

Rosco P. Coltrane (209368) | more than 6 years ago | (#23400760)

I can't seem to find the artist's view of the failed mission, with the Phoenix lander splattered all over the place and bits falling back down on Spirit and Opportunity...

Re:Good article and GREAT PICTURES of the Phoenix (4, Funny)

Thanshin (1188877) | more than 6 years ago | (#23400862)

I can't seem to find the artist's view of the failed mission, with the Phoenix lander splattered all over the place and bits falling back down on Spirit and Opportunity...
They should keep both versions hidden and then show the correct one after knowing the result. Like in sports events.

"The lander exploded in, according to latest estimations, about 13,000 pieces. As you may see in this depiction, some of those pieces may hit opportunity and start a chain reaction of exploding landers."

Re:Good article and GREAT PICTURES of the Phoenix (2, Interesting)

evanbd (210358) | more than 6 years ago | (#23402564)

The Mars Scorecard [anl.gov] .

Mars currently leads, 20:19, though Earth is making a strong showing this decade.

Re:Good article and GREAT PICTURES of the Phoenix (1)

blind biker (1066130) | more than 6 years ago | (#23403536)

Phoenix should level the score. Let's hope it does.

Re:Good article and GREAT PICTURES of the Phoenix (1)

Phoenix Wright (1153585) | more than 6 years ago | (#23401520)

That looks nothing like me.

Re:Good article and GREAT PICTURES of the Phoenix (1)

CraftyJack (1031736) | more than 6 years ago | (#23406466)

You could also just go to the mission page [arizona.edu] .

Re:Good article and GREAT PICTURES of the Phoenix (1)

David Jao (2759) | more than 6 years ago | (#23407632)

There is also an awesome graphic novel [technologyreview.com] from Technology Review, containing an entertaining yet factual account of the history of the Phoenix mission.

Slashvertisement (0, Redundant)

mrbluze (1034940) | more than 6 years ago | (#23400512)

Here we go again, just another poorly written slashvertisement for.. uhmm..

Actually, this is a really good posting.

Trips to grandMars' house (5, Funny)

mrbluze (1034940) | more than 6 years ago | (#23400528)

This is not a trip to grandma's house. Putting a spacecraft safely on Mars is hard and risky.

NASA: Oh my, Mars, what big craters you have!

GrandMars: All the better to SWALLOW you with.. grrrr!

Re:Trips to grandMars' house (-1, Offtopic)

Thanshin (1188877) | more than 6 years ago | (#23400626)

My same themed joke (that I latch to yours to keep an order) was:

'This is not a trip to grandma's house. Putting a spacecraft safely on Mars is hard and risky,' said Ed Weiler,
So no wolves then?

Re:Trips to grandMars' house (2)

Goffee71 (628501) | more than 6 years ago | (#23400846)

I was travelling through space one day,
when a shiny red planet came my way.
It was big and looked rather hard,
would my chute and jets help me retard?
To see if I could find life in the icy clay?

Good luck Pheonix

Slow to about 8 kilometers per hour. (1, Interesting)

Thanshin (1188877) | more than 6 years ago | (#23400658)

In seven minutes, the spacecraft must complete a challenging sequence of events to slow to about 8 kilometers per hour...
Why reducing the box? Is there any reason to discard a higher speed landing?

What if they find a way of slowing down to 16kmh, they abandon the mission?

I'm not talking about considering compressing time continuum to extend those 7 minutes, but it seems there are possibilities that could still be considered, like hardening the legs, finding a softer spot to land, finding a lower landing spot to extend braking time, etc.

Re:Slow to about 8 kilometers per hour. (5, Interesting)

ledow (319597) | more than 6 years ago | (#23400708)

Because even at 8km/h you can do serious damage. Any lander has to be extremely light for takeoff from Earth and the transit to Mars, contain extremely fragile equipment, and end up there in one piece. "Bouncing" off Mars is not an option. That requires heavy, expensive materials, or some sort of complicated landed shield arrangement (e.g. giant inflatable bubble) that all add years of work and millions to the cost of the project. You could literally double or treble the cost of the entire project by "beefing up" the lander.

Plus, it has to land under autonomous control, so you really have no idea how fast it actually landed or exactly where until several minutes after it has landed - so coming in a little too fast isn't a good option, neither is a stray patch of rock (there are few "soft spots" on Mars, by the way - it's mostly rock). Much better to land as gently as you can manage and do your braking manoevures in the "air" as you come down. You've got plenty of time, the physics are easier to calculate, and there's less to go wrong.

The first few hours of a new lander's life on another planet are basically checking that everything still works, even with all the gentle landings in the world, things get broken that cost MILLIONS to put them up there. 50% of the things still never make it to the planet operational, even with all the good will in the world behind it. You want to spend MULTIPLES of the cost of the entire project on making the landings more difficult, more violent and less reliable when we can't even get half of what we send onto the planet successfully?

Re:Slow to about 8 kilometers per hour. (1)

MichaelSmith (789609) | more than 6 years ago | (#23400772)

Because even at 8km/h you can do serious damage.
Must be why I have such a bad feeling about this one. Lately the hard landings have been the most successful ones.

Re:Slow to about 8 kilometers per hour. (1)

Thanshin (1188877) | more than 6 years ago | (#23400794)

Because even at 8km/h you can do serious damage.
You could replace 8km/h for 4km/h in your entire reasoning and it would still stand, yet neither would address my point.

I do understand that 8km/h is not an arbitrary limit. However, stating the landing problem as "There is only one chance! They absolutely must do this or everything will fail!" seems much more oriented to make the news more exciting than because of 8km/h being the perfect speed to put the lander on Mars.

Re:Slow to about 8 kilometers per hour. (0)

Anonymous Coward | more than 6 years ago | (#23403672)

I suspect you know nothing about engineering. These things are designed. When you design something you have trade off. You could make it withstand a huge impact if it was solid steel, but it wouldn't do much after it hit but sit there. If you wanted to make a lander than handled 16 km/h, you'd have to add more shock absorbing and remove sensitive instruments. If you set the limit to 4 km/h, you can remove weight from shock absorption and add a lot more instruments. It's a trade off. JPL has a huge group of insanely smart people spending thousands of hours arguing which trade off is best. The results of all that debate is normally published, but I don't feel like looking it up.

With the costs involved nothing is arbitrary it's all analyzed to death.

Re:Slow to about 8 kilometers per hour. (1, Insightful)

Anonymous Coward | more than 6 years ago | (#23405546)

There is only one chance. A few things can be slightly off the mark, including the touchdown velocity, without losing the mission, but entry, descent, and landing has the least margin for error and most opportunities for outright disaster of any stage of the mission. They can't even delay it. Entry, Descent, and Landing is historically when the greatest number of mission failures occur.

8 km/h is the target touchdown velocity. They'll come pretty close, probably with a couple km/h of that speed, but it probably won't be exactly that. 16 km/h might even be survivable. The point is 25,000 km/h, or even 100 km/h is not survivable.

But there's a whole lot of steps before that:

* Navigation - Mars Climate Orbiter missed orbit by a fraction of degree. It failed. Coming in too steep would also mean failure.
* Entry - at 25,000 km/h, the spacecraft is toast if its protection fails.
* Heat shield separation - If this doesn't happen, the guidance system can't operate.
* Reaction control system - Keeps the lander stable in flight. Tumbling would tear it apart.
* Parachute deployment - Obvious
* Parachute release - If it fouls the probe, it can't deploy its solar panels
* Retrorocket - Has to coordinate with guidance and RCS to slow to touchdown speed and stay in the right orientation. Has to fire on demand. Can't explode.
* Leg Deployment - All must deploy for a stable touchdown. The leg deployment on Mars Polar Lander jarred the touchdown sensor, causing the engines to shut down before touchdown. Mission failed.
* Engine cutoff - Has to happen just a few feet above the ground to avoid damaging the lander with backblast and debris.
* Touchdown - Legs are partially collapsible to cushion the landing.

If the speed is right, and it misses any large rocks, and the parachute doesn't drift down on top of it, and all the other things above go right, at this point EDL was successful. After being shaken and hurled into space onboard a rocket, drifting dormant in the cold for 8 months, plumetting through the atmosphere at outside temperatures that would melt the lander itself, bouncing at parachute opening, facing the harsh wind at heat-shield separation, and freefalling several feet to the ground, now the hope is the delicate motors, joints, and electronics on the probe still work.

The more you know about what could go wrong, the more you wish EDL was over already.

Re:Slow to about 8 kilometers per hour. (-1, Troll)

Erie Ed (1254426) | more than 6 years ago | (#23400806)

You could literally double or treble the cost of the entire project by "beefing up" the lander.
treble??? what is this new unit that you speak of...

Re:Slow to about 8 kilometers per hour. (1, Informative)

ledow (319597) | more than 6 years ago | (#23401088)

Are you seriously telling me you've never seen the word treble used in that context?

treble (trb'l) adj. meaning Triple

Perfectly valid English in every English dialect and has been for hundreds of years (Answers.com actually pointed me at a George Eliot quote as an example of its use). Treble sounds better in a sentence such as that one (it matches better with "double" than triple would and feels more natural for most native English-speakers) and there are certain places where we British prefer treble to triple (triple is usually an action, "he tripled the number" whereas treble is usually a statement "awarded treble damages") although they are very mix-and-match. You can even have trebled, trebling, trebles (nothing to do with Star Trek).

Re:Slow to about 8 kilometers per hour. (0)

Anonymous Coward | more than 6 years ago | (#23401272)

treble (trb'l) adj. meaning Triple
Nice quote, except you used it above as a verb. You fail it.

Re:Slow to about 8 kilometers per hour. (1)

JohnConnor (587121) | more than 6 years ago | (#23402100)

It's a verb too:

to treble (third-person singular simple present trebles, present participle trebling, simple past and past participle trebled)

1. (transitive) To multiply by three; to make into three parts, layers, or thrice the amount.
2. (intransitive) To make a shrill or high-pitched noise.
3. (intransitive) To become multiplied by three or increased threefold.

From: http://en.wiktionary.org/wiki/treble [wiktionary.org]

Re:Slow to about 8 kilometers per hour. (0, Offtopic)

The real PoD (734939) | more than 6 years ago | (#23401290)

Not owning a dictionary is no excuse.
define: treble [google.com]

Re:Slow to about 8 kilometers per hour. (2, Funny)

JosKarith (757063) | more than 6 years ago | (#23400988)

"You want to spend MULTIPLES of the cost of the entire project on making the landings more difficult, more violent and less reliable when we can't even get half of what we send onto the planet successfully?"
He must work for the government then...

It's not the landing speed ... (0)

Anonymous Coward | more than 6 years ago | (#23406304)

It's those darn Martian death rays that are really the cause of so many lost spacecraft. You want your proof of life there it is, 50% loss of spacecraft.

Re:Slow to about 8 kilometers per hour. (1)

pipatron (966506) | more than 6 years ago | (#23400710)

Maybe you should call some engineer at NASA and tell them about these ideas?

Re:Slow to about 8 kilometers per hour. (1)

Thanshin (1188877) | more than 6 years ago | (#23400776)

Maybe you should call some engineer at NASA and tell them about these ideas?
You mean I should call the journalist responsible for the press release and tell him to remove sensationalism when writing about serious matters.

"the spacecraft must complete a challenging sequence of events"? Come on.

Re:Slow to about 8 kilometers per hour. (1)

pipatron (966506) | more than 6 years ago | (#23400972)

Yes, you could also contact the journalist but that would be rather futile. :)

Re:Slow to about 8 kilometers per hour. (2, Funny)

stoofa (524247) | more than 6 years ago | (#23400774)

In seven minutes, the spacecraft must complete a challenging sequence of events to slow to about 8 kilometers per hour...
Is anyone else picturing these challenging sequence of events as some engineer leaning on a red button with all his might while screeching "Brake, damn you!" at the top of his lungs?

Maybe that's where the name idea came from...

Re:Slow to about 8 kilometers per hour. (1)

timmarhy (659436) | more than 6 years ago | (#23400784)

this is why they are NASA engineer's sending craft to other planets, and your just some bozo posting stuff on /.

not wanting to be harsh, but it doesn't sound like you've thought it through too much. try running your car into something at 16km/hr and get back to me.

Re:Slow to about 8 kilometers per hour. (1)

Thanshin (1188877) | more than 6 years ago | (#23400830)

not wanting to be harsh, but it doesn't sound like you've thought it through too much. try running your car into something at 16km/hr and get back to me.
So, your way of studying the landing speed limit of an object in another planet is crashing you car into objects.

Well, now that you started with the ad hominem, let me do a follow up.

Obviously just about everyone who reads this news understands the implications of a landing at 16km/h. Please make an effort to avoid thinking anyone might be under your intellectual level; you'll fail more often than not on that one.

Re:Slow to about 8 kilometers per hour. (2, Funny)

JosKarith (757063) | more than 6 years ago | (#23401012)

"So, your way of studying the landing speed limit of an object in another planet is crashing you car into objects."

Well, it seems to work for particle physicists...

Re:Slow to about 8 kilometers per hour. (1)

ceroklis (1083863) | more than 6 years ago | (#23403256)

The quote you give is overly dramatic. There is a sequence of events that must all happen at a precise time, and all succeed. Whether this sequence lasts 1 minute or 1 hour doesn't make it more or less difficult.

The speed will not be twice what the spacecraft can withstand... for a good reason: They run simulations with varying entry angles, entry speeds, wind speeds, etc... to figure out the highest landing speed possible, and design for that.

There is no need to harden anything if the design is sound. If a failure occurs (for example the chute not opening), hardened legs with not save you.

The landing site is constrained by the scientific objectives of the mission. There is not much leeway in this area.

whose grandma ? (4, Funny)

Rosco P. Coltrane (209368) | more than 6 years ago | (#23400752)

This is not a trip to grandma's house

You've never met my grandma. As a kid, going there felt like a 25,000 mph trip, and there are still skidmarks from my shoes trying wildy to decelerate while my parents dragged me into the house. And about half of the times they tried taking me there, it failed too...

Re:whose grandma ? (4, Funny)

mrbluze (1034940) | more than 6 years ago | (#23400756)

And about half of the times they tried taking me there, it failed too...
Did it hurt when you slammed into the front door at 8km/h?

Re:whose grandma ? (5, Funny)

shadowcabbit (466253) | more than 6 years ago | (#23401418)

It's just under 5 mph. Dude, I've run head-first into wasll fastre than that no purpoes, adn it didn't hutr me oen bit.

fewer than half? (1)

notgm (1069012) | more than 6 years ago | (#23400764)

how many international missions with the end goal of landing on mars have there been?

this guy makes it sounds like more than just a handful, and I can only recall 3.

is there some vast international mars landing conspiracy that i'm unaware of?

Re:fewer than half? (4, Informative)

jamesh (87723) | more than 6 years ago | (#23400926)

is there some vast international mars landing conspiracy that i'm unaware of?


Yes. The details are hidden away on wikipedia where you'll never find them! Some details:

Mars 2 (1971): Landed but lost contact within minutes
Mars 3 (1971): Same
Viking 1 (1974): Landed and remained operational for 6 years
Viking 2 (1974): Landed and remained operational for 3 years
Phobos 1 (1988): Lost on the way to Mars
Phobos 2 (1988): Got into orbit, took some photos, then failed

The more recent ones you probably know about. To be fair, the Phobos 1 and 2 missions were planning to land on Phobos, not Mars, so maybe they don't count.

Don't Forget the Space Race! (2, Informative)

FurtiveGlancer (1274746) | more than 6 years ago | (#23401414)

According to Russian Space Web [russianspaceweb.com] , the USSR attempted four Mars landings with only two actually reaching the planet. Of those two, only one failed upon landing.

Re:fewer than half? (0)

Anonymous Coward | more than 6 years ago | (#23405818)

The details are hidden away on wikipedia where you'll never find them!
Sorry, notgm can't help it; He's Chinese.

Re:fewer than half? (1)

PudriK (653971) | more than 6 years ago | (#23401458)

I count only three non-American Mars landing missions, too: Russian M-71 and M-73, and Europe's Beagle 2 on Mars Express. But perhaps he was referring to the numerous international Mars orbit and flyby missions which have also failed.

See Astronautix.com [astronautix.com] for details.

Re:fewer than half? (1)

cnettel (836611) | more than 6 years ago | (#23402246)

Wikipedia whoring. [wikipedia.org]

Quite a few included rovers/landers in one sort of another, and many failed. The first attempt was a Soviet probe in 1962, it didn't even leave Earth orbit properly, but it was a planned mission.

Re:fewer than half? (1)

Iron Condor (964856) | more than 6 years ago | (#23410676)

you've probably seen it by now, but just in case you haven't: just about 40 attempts [anl.gov]

#space on irc.freenode.net Phoenix Landing Party (5, Informative)

slinted (374) | more than 6 years ago | (#23400770)

#space on irc.freenode.net is hosting a Phoenix Landing Party on Sunday, May 25 to share in this momentous occasion for planetary exploration. We'll be following NASA TV through landing, then ogling the raw images when they are released several hours later. Historically, #space has been a hub for collaborative efforts in image processing by the space enthusiast community (Mars Exploration Rovers, Huygens, etc). Hope you can join us!

Re:#space on irc.freenode.net Phoenix Landing Part (1)

tetrahedrassface (675645) | more than 6 years ago | (#23400852)

Great! I love #space on freenode. It is a great friendly, fun and clean channel. I can't wait for Phoenix to land. Seems like yesterday that we were doing this with the rovers.

Come by for a visit folks and help us celebrate the landing, you won't be disappointed.

This is not a trip to grandma's house (1, Funny)

Anonymous Coward | more than 6 years ago | (#23400792)

Ah. That'll depend on whos grandma we're talking about, wouldn't it?

Hard and Risky??? (-1, Flamebait)

tgatliff (311583) | more than 6 years ago | (#23400812)

Is it just me, or is anyone else tired of hearing the "hard and risky" and "needle in a haystack" type phrases??

The first couple of times you do something is it hard and risky... After that, it is kind of part of the job description. Meaning, I am getting a little tired of them trying to use this excuse to cover their butts in case something goes unexpectedly wrong. It is a job, and they get paid quite well for doing it, I might add. I also understand that they are quite smart, but I am sure there is a huge line of smart people who would love to replace them.

In short, NASA and JPL needs to stop hiding behind corporate committees using the "Hard and Risky".. and the "Needle in a Haystack" type phrases and accept the responsibility of the job description. When they succeed, we praise them, but when they fail they need to know that there are consequences for messing up. Meaning it actually is someone's fault, and they will be fired when a mistake is made... Maybe by doing so we can avoid the simple metric to english conversion issues of the past...

Re: Hard and Risky??? (4, Funny)

Thanshin (1188877) | more than 6 years ago | (#23400924)

Maybe by doing so we can avoid the simple metric to english conversion issues of the past...
Converting metric to english units is clearly harder than anyone thought and much riskier.

They're just learning from past mistakes.

Much like the experienced worker that estimates a month for a two hour job.

Re: Hard and Risky??? (3, Insightful)

Anonymous Coward | more than 6 years ago | (#23401068)

Just because you do something a couple times, it does not mean that it is no longer hard and risky.

I work in a factory, and the first time that someone uses something like a table saw, they are nervous. I is a dangerous tool and could seriously injure them if they are not careful. But most of the injuries I see cause by power tools are by people who have gotten too comfortable with them and have forgotten about the risk involved.

commonplace != safe and easy

Re: Hard and Risky??? (0)

tgatliff (311583) | more than 6 years ago | (#23402176)

I am pretty sure that OSHA would completely disagree with you...

Safety is built on putting together good procedures that you follow every time. It is only when you get careless and remove these procedures that people get hurt... Countless industrial and aircraft accidents back this up...

This is also the reason why flying is safer than it used to be, I might add... Meaning, checklists and safety procedures is what makes things reliable and safe to use...

Re: Hard and Risky??? (2, Interesting)

Anonymous Coward | more than 6 years ago | (#23401106)

It's always hard and risky, even the 10th time you do it. Mostly because each success raises the bar for the next mission. First you land a shoebox sized rover, then a golf cart, then something the size of a Mini. Those are orders of magnitude more difficult in turn.

Paid quite well? JPL pays slightly under industry wages, but it IS a nice place to work, and glamorous. NASA pays substantially lower (government civil service jobs.. but there are some intangible benefits that are hard to quantify, and some that are)

People do get fired for making mistakes.

It wasn't JPL or NASA who supplied the data in pounds instead of the contractually required Newtons. JPL has been metric for decades.

Re: Hard and Risky??? (1)

tgatliff (311583) | more than 6 years ago | (#23402248)

All I am saying is I am having a hard time seeing why it is so much harder than it was in the 1970's when they landed the Viking missions, and it was the first time they ever touched down on the planet. Also, did I mention that both missions were successful...

I am not saying the job is easy, but many jobs are not. With the amount of money at stake on each mission, however, failures must to be rare, and not part of doing business. The groups in the 1960's understood this, and it is not because they had more money. It is because they accepted accountability...

Re: Hard and Risky??? (1)

barath_s (609997) | more than 6 years ago | (#23404002)

it is not because they had more money Phoenix cost 520 million $ in 2008 dollars. Vikings cost 935 million in 1974 dollars (was nearly $3 billion measured in 1997 dollars, more in 2008 dollars) http://www.nasawatch.com/archives/2008/05/the_actual_cost.html [nasawatch.com]

Re: Hard and Risky??? (1)

Iron Condor (964856) | more than 6 years ago | (#23410822)

All I am saying is I am having a hard time seeing why it is so much harder than it was in the 1970's when they landed the Viking missions, and it was the first time they ever touched down on the planet. Also, did I mention that both missions were successful...

If "success" is defined as "slam something, anything, into the ground somewhere, somehow, that can still send a couple pictures back afterwards". Sure. Phoenix, of course, weighs an order of magnitude more, has to hit a landing spot chosen from science reasons (and not for "make it easy on the lander" reasons) and carries sensitive scientific instrumentation that still has to be able to do quantitative chemistry analytical work after the landing.

...and suddenly the whole thing becomes a whole lot harder. Now you tell folks that they have to do it on a fraction of the budget of Viking and you've just made it riskier.

There are four dimensions to systems engineering and at most three of them are free. Once you decide to do something fast, good AND cheap, the fourth dimension, risk, will go wherever it damn well pleases.

Re: Hard and Risky??? (1)

morgan_greywolf (835522) | more than 6 years ago | (#23401112)

The first couple of times you do something is it hard and risky... After that, it is kind of part of the job description.
And how many times has NASA successfully landed a spacecraft on the polar regions of Mars? Oh, right, never.

Re: Hard and Risky??? (5, Insightful)

cculianu (183926) | more than 6 years ago | (#23401232)

Stop being a dick. There's a lot that isn't under their control. They are landing a pre-programmed (not even remote-controlled) spacecraft on another freakin' planet!

Cut them some slack! Most of us slashdot readers have trouble getting an Apache install right the first time through. These guys are doing nearly the impossible and they don't get much of a chance to fix any mistakes.

There are like THOUSANDS of possible things that could go wrong with the landing that DON'T because the engineers did their job. If you have ever engineered anything, you know how much you have to think ahead. They sat really hard and long and tried to perfect the landing process.

But it's darned hard. Mars is really really really far away. The data transfer speed to the lander is like 16KB/s on a good day. You can't send realtime flight data and have a pilot fly the thing with a joystick (because of the latency and the bandwidth is just too limited). You just have to build smart control logic into the thing and hope for the best.

And -- what can ruin the whole thins is -- just one largish rock in the wrong place and the whole mission is a failure. Historically, only 5 out of 13 landers made it to the surface operational!

So, stop being a douche and start appreciating how hard this all is. And it isn't just NASA -- the Brits also tried and failed. It's hard. NASA is doing a great job. Let's see you send 100LBS of spacecraft millions of miles away and have it get there safely. It's pretty amazing it ever worked at all!

Oh and what "corporate committes"? Last I checked NASA was a government agency.

Stop thinking like a corporate douch and start thinking like a scientist. These guys are smarter than you or I and give them some respect.

Re: Hard and Risky??? (0, Flamebait)

tgatliff (311583) | more than 6 years ago | (#23401980)

Exactly... And they also landed 2 Viking crafts in 1976 without 1/10th the tools or even computers for that matter that we have now... And both missions were successful. They also put men on the moon without those tools or computers as well in under a decade where we are now proposing to do it in double the time just to recreate what they did in the 1960's.... Were these guys just luckier?? No... The difference was that these guys put aside the "hard and risky" non-accountability crap and got the job done...

The argument of 1000's of things that could go wrong are obvious as they are not the only ones who deal with predictable failure rates. All engineers (including me) do... Also since hundreds of millions of us tax payers dollars are at stake on every missions, I dont think it is unreasonable to hold people accountable for obvious failures....

Re: Hard and Risky??? (1)

cculianu (183926) | more than 6 years ago | (#23402096)

There is some nonzero chance that it will land on or near enough to a rock so as to not be properly operational. If it lands on a rock it can roll off of it and end up upside-down. Or even if it's not on a rock, but just next to one, it can't deploy its solar panels.

There is little that can be done about this practically. It's just they hope it won't happen. They chose a landing site that has few if any large rocks, and they are just hoping for the best -- but there still is a nonzero probability they will get horribly unlucky and land on a rock.

This is one example of something beyond anyone's control and that isn't an obvious failure.

Re: Hard and Risky??? (1, Insightful)

tgatliff (311583) | more than 6 years ago | (#23402422)

Being an engineer myself, I would say that this looks like a serious design flaw to me... Meaning, if a little rock could ruin the work of thousands of people, hundreds of millions of dollars in project funding, and years of work, I am left scratching my head of why this landing strategy was a good idea?? I mean, as the Viking missions showed, there are more than one way to land a craft on a planet...

In short, scientists study, but all engineers are very comfortable with the idea of managed risk. It is part of nearly every design that is built. Yes, mistakes do occur from time to time, but I continue to see on every mission they do people jumping up and down whenever their craft successfully lands. The first couple of times they do this it is understandable, but after a couple of times you really have to start wondering if they are not designing their systems by looking at all the things that could go wrong, but rather just with the number of things they need to get it to get right...

Re: Hard and Risky??? (1)

Anonymous Coward | more than 6 years ago | (#23401478)

The first couple of times you do something is it hard and risky... After that, it is kind of part of the job description. Meaning, I am getting a little tired of them trying to use this excuse to cover their butts in case something goes unexpectedly wrong. It is a job, and they get paid quite well for doing it, I might add. I also understand that they are quite smart, but I am sure there is a huge line of smart people who would love to replace them.

Yea, we should have this Alaskan crab fishing thing down pat too, 0 fatalities. Or computer security, many people get paid well to fix that, why do we still mess that up?

It's not just NASA, the Russians and Brits [wikipedia.org] fail at this too. They suck more then NASA [wikipedia.org] , even.

Maybe rocketing state of the art probes to another planet and landing them there IS STILL ACTUALLY HARD AND RISKY.

Re: Hard and Risky??? (1, Insightful)

tgatliff (311583) | more than 6 years ago | (#23402536)

Using the Alaskan crab fishing as an example is laughable at best... The only reason these guys are able to pull off the stupid things they do is because OSHA has not decided to put an end to it...

Meaning, no job is just accepted to be risky by nature, because there really is no reason for it. As OSHA has shown time and time again, safety is always built on the procedures put in place that you follow every-time. It is these procedures that keep people safe. It is only when people get lazy, and stop following the procedures that they get hurt...

Place your bets here (-1, Troll)

LaTechTech (752269) | more than 6 years ago | (#23400870)

With these odds being slightly better than roulette; someone might as well start collecting money*...

50/50

Success [wikipedia.org] /Lawn Dart [wikipedia.org]

*Collection fees non negotiable

insidious corepirate nazi propaganda machine... (-1, Troll)

Anonymous Coward | more than 6 years ago | (#23400928)

continues cranking out fiction/fluff at record levels, whilst we wait for the next ??? to fall. yuk, i mean phewww. fortunately, there's nowhere left to hide. the lights are coming up all over now. see you there?

Argh! units units units! (3, Funny)

fantomas (94850) | more than 6 years ago | (#23401028)

"21,000 kilometers per hour..." - Arggh! Ed (Weiler)! some of your guys are using metric units! Have a quick check round the lab and make sure they all are! Maybe the quiet guy in the corner in charge of retro rockets is still using miles not kilometres!

I'm sure you have, but you know, we've been here before... ;-)

Re:Argh! units units units! (2, Funny)

bsDaemon (87307) | more than 6 years ago | (#23402090)

Good thing if Phoenix crashes, it'll just rise from the dead and reassemble itself, thereby completing its mission, good as new.

Very good strategy on behalf of NASA, I'd say.

Re:Argh! units units units! (1)

RKBA (622932) | more than 6 years ago | (#23407248)

Actually, Phoenix is itself a resurrection of the failed Mars Polar Lander [wikipedia.org] that I worked on a decade ago before my retirement from JPL (I wrote the firmware for the meteorology sub-system). I wish Phoenix well.

Re:Argh! units units units! (0)

Anonymous Coward | more than 6 years ago | (#23404346)

How fast is that in Libraries of Congress???

Re:Argh! units units units! (1)

Iron Condor (964856) | more than 6 years ago | (#23411260)

In a heliocentric, sun-fixed coordinate system, the Earth (and thus the LOC) move at about 30km/s which comes to about 108000 km/h - about 5 times faster than the Phoenix lander.

Then again, nobody is trying to land the thing on Mars.

Slow transfer rate to Mars (4, Interesting)

cculianu (183926) | more than 6 years ago | (#23401168)

From the media kit PDF about Phoenix:


The helical antenna and a monopole UHF antenna, also mounted on the deck, will be used for relayt elecommunications during the months of operation after landing. The lander can send data at rates of 8,000 bits per second, 32,000 bits per second or 128,000 bits per second.


Wow, that isn't a fast transfer rate. That's about 1KB/s, 4KB/s, and 16KB/s, respectively. I guess you don't need too much more -- but still, I bet it's slower than they would like. The high resolution camera alone probably produces images that are a few megabytes in size. Let's say the images are like 4MB -- Transferring 4 MB at 1KB/s takes about an hour!


Given the slow xfer speeds and limited hardware they probably use -- I think it would be fun to be a programmer for NASA. That's one of the few applications where efficiency of communications, small memory footprint and efficient CPU usage probably still count for something.. I bet you everything they do when it comes to the software running on the lander tries to be as efficient as possible (especially communications-wise).

Also, isn't there something like an few minutes of latency for light to reach us from Mars? You can't even really do any really realtime interaction with the onboard computer on the Phoenix lander.. Imagine typing into a shell and waiting a minute for your characters to appear! Ouch! So I bet you they have to premeditate a lot of the changes they make to the software or operating environment way a head of time -- they probably just upload scripts of commands when updating the software or filesystem, etc.


I wonder how much freedom they give the people communicating with the lander. Do they triple-check every command sent to it to make sure noone does the inadvertent 'rm -fr /'?

Re:Slow transfer rate to Mars (1)

GbrDead (702506) | more than 6 years ago | (#23401938)

Imagine typing into a shell and waiting a minute for your characters to appear!

Actually, this was happening quite frequently back in the dial-up days.

Re:Slow transfer rate to Mars (1)

sconeu (64226) | more than 6 years ago | (#23403444)

Dialup schmial up.

This happened all the time back in '83 and '84 on a VAX 11/780 at UCSC. Come the end of the quarter, the VAXen would all be overloaded (we're talking load averages over 30, with spikes up to 70).

You'd type a command, go away and get a cup of coffee, and maybe when you got back, you'd get an acknowledgement that you actually did something.

However, in tribute to the 4.2BSD guys (original Berkeley, not Open/Net/FreeBSD), even with this insane overload, the VAX... Did... Not... Crash.

Re:Slow transfer rate to Mars (2, Interesting)

silverpig (814884) | more than 6 years ago | (#23403442)

"Also, isn't there something like an few minutes of latency for light to reach us from Mars? You can't even really do any really realtime interaction with the onboard computer on the Phoenix lander.. Imagine typing into a shell and waiting a minute for your characters to appear! Ouch! So I bet you they have to premeditate a lot of the changes they make to the software or operating environment way a head of time -- they probably just upload scripts of commands when updating the software or filesystem, etc." Yes the lag time is several minutes, depending on the relative positions of the Earth and Mars. For the mars rovers the task is quite interesting. Imagine trying to control a remote controlled car around an obstacle course where you have to wait 20 minutes to see the results of your actions. NASA wrote software for the rovers which makes the process largely automatic. They tell the rover to go to a certain place, and the rover has software which basically figures out the best way to get there.

Re:Slow transfer rate to Mars (0)

Anonymous Coward | more than 6 years ago | (#23403734)

From the media kit PDF about Phoenix:



I wonder how much freedom they give the people communicating with the lander. Do they triple-check every command sent to it to make sure noone does the inadvertent 'rm -fr /'?

'rm -fr /' is not what you need to worry about. That can be easily defended against. The one to worry about is the inadvertent '\rm -fr /'.

Re:Slow transfer rate to Mars (1)

tpheiska (1145505) | more than 6 years ago | (#23404270)

I wonder how much freedom they give the people communicating with the lander. Do they triple-check every command sent to it to make sure noone does the inadvertent 'rm -fr /'?
Actually they've messed up a satellite this way. A detaild explanation can be found here [nasa.gov] , quote "A modification to a spacecraft parameter, intended to update the High Gain Antenna's (HGA) pointing direction used for contingency operations, was mistakenly written to the incorrect spacecraft memory address in June 2006. The incorrect memory load resulted in the following unintended actions ...". It's actually pretty amazing that they've managed to reconstruct the whole sequence of events, most likely by using simulators.
Furthermore, it's not just the wrong commands you have to worry about, but also bit flips in the signal, bit flips and errors in the memory caused by solar wind and even ultra-high-energy cosmic rays that you cannot even shield against, even with lead. Many precautions are taken, such as using old chips that are not so densely packed.
Anyway, my point is, you can have many sorts of errors in the computer programs, human, solar, or even extrasolar.

Re:Slow transfer rate to Mars (2, Interesting)

ChrisA90278 (905188) | more than 6 years ago | (#23405680)

The typically have a model of the spacecraft in the lab. any change to the software gets uploaded and tested in the lab. There will be quite a bit of formal testing using a detailed written test plan. Then there is some kind of a change review bord that meets and reviewis the tests and the plan. Finally the changes get packaged up. The they test the upload procedure on the lab simulator. Then finaly the change is uploaded.

Typing into a shell is not only slow but far to risky. Everything gets tested for a good long time and many eyes look it over

It you are the kind of programmer that like just hacking away and changing code until it work this kind of work is not for you. These guys will write up a design and defend it to a review group then they do the code and then they will do a line by line walk through then they go to test. the process is very slow going and productivity runs at well under 200 lines of code per month per engineeer.

Re:Slow transfer rate to Mars (1)

dotancohen (1015143) | more than 6 years ago | (#23409406)

bord? reviewis? That you, Golum?

the process is very slow going and productivity runs at well under 200 lines of code per month per engineeer.
They inherited the Longhorn / Vista staff?

Re:Slow transfer rate to Mars (1)

muhadeeb (1062676) | more than 6 years ago | (#23414378)

They can do better than that. They could have outsourced the code to either apple or microsoft or go open source. With open source, it could be cheaper.

Re:Slow transfer rate to Mars (0)

Anonymous Coward | more than 6 years ago | (#23413790)

Actually, it's a relay from the surface of Mars to a spacecraft orbiting around Mars. Then the data is sent on a long haul at up to a few Mbps back to earth.

The "light time delay" is about 20 minutes one way, so there's no interactivity. Everything is done with sequences (like a script) and timed execution (like using cron).

Processor resources? The radio on Phoenix (Electra) has a 25 MHz SPARC V7. I don't know what the spacecraft flight computer is, but given its age, it's probably a Rad6000 (think slower than the MIPS4000 in the first generation Tivo)

How much freedom? There's a lot of eyes watching over your shoulder.

Pre-Dupe (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#23401346)

I look forward to reading about it on Slashdot when posted on the 25th.

Several readers (0, Offtopic)

esocid (946821) | more than 6 years ago | (#23401984)

I had no idea I was more than one person [slashdot.org] .

Umbrella Corporation (0, Offtopic)

Timberwolf0122 (872207) | more than 6 years ago | (#23402068)

Is it me or do the solar panels on the Phoenix lander look remarkable like the http://en.wikipedia.org/wiki/Umbrella_Corporation [wikipedia.org] Umbrella Corporation logo? What with the reputation of Mars (Ghosts of Mars, The Red Planet, Doom, that one outer limits, etc) I'm not too sure I like a resident evil probe up there....

this is goatSex (-1, Troll)

Anonymous Coward | more than 6 years ago | (#23404112)

half as many (2, Insightful)

sgt scrub (869860) | more than 6 years ago | (#23406918)

wouldn't there have been at least half as many trips to mars if they weren't so hell bent on trying to figure out if there is life there? could we get on with the process of making it a habitable place instead of waisting trips on "theological i told you so" science projects?

euro bashing nasa again (0)

Anonymous Coward | more than 6 years ago | (#23418932)

Just more euro pricks rattling the cage against nasa.. Same old garbage...

P.S. I hope they 'nasa' succeed so the euro pricks can suc-seed too!!!
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