Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Philae has landed

bbc.com

Post reply on HN
Print view View original

191–200 of 309 posts

Re: Philae has landed

#191

Post by return0 »

throwit99 wrote: post #105
return0 wrote: post #97

Earlier quoted context omitted.

I 'd dare you to specify what's more important where your money should be spent.

Health, welfare, lowering taxes, employment.... y'know, things that enrich real peoples lives. Space toys and exploration are fun for those working on them, but will this event transform civilisation? Nope. Did the moon landing really transform civilisation? Nope.

Sure i could point out that this mission could indirectly advance health technology (landing a robot on a comet is no small technological feat. The side-benefits of big research projects, such as the WWW that allows us to argue here, are no small thing)

But most importantly it bothers me that you think that risking a relatively small amount of money to expand our limits is not important. IF it were a "showoff" mission or a re-enactment of the moon landing, i would agree with you but this is about going into unknown territory. When Columbus set off to find a short path to the Indies, i bet someone would think the money was frivolously spent, but this guy never made it to the history books.

If you insist that we shouldn't take risks like this, you are literally asking the civilization to stop.

Re: Philae has landed

#192

Post by jnem »

Total non-sequitor but...I'm surprised no one else has yet made the observation that Philae Lander put together is philaender, or philander. Juvenile post of the day award anybody?

Re: Philae has landed

#193

Post by phaemon »

ahallock wrote: post #186
yequalsx wrote: post #177

Earlier quoted context omitted.

Few people agree that taxation is the same as theft. You appear to be someone who does have this view. That is fine but it is not a commonly held belief and generally is subject to derision and down voting. This should not come as a shock to you. A very large percentage of people believe that having a functioning government is necessary and taxation is a necessary component for this. There are no examples of large po…

Taxation might not fit the strict definition of theft (easy when the gov creates its own jargon), but it is the threat of force to take property from someone against their will. I mean, how many of us are giving money directly to the gov by our own volition? I don't know of anyone. We were born into this system and we never agreed to it. Let's at least be honest about that. > There are no examples of large population…

> it is the threat of force to take property from someone against their will.

No it's not. It's the threat of force against people who use that market and then refuse to pay the fees they owe. Any service can (and would) do the same via the legal system. I've never paid the US government a penny, because I don't use their market.

> We were born into this system and we never agreed to it.

You certainly have the option of leaving that market if you don't like its fees. Or of attempting to get them changed by voting for a representative that shares your views.

> Would you say if most of the world were enslaved that because there are no examples of a free people, it's not worth while to try?

If all the examples of 'free people' were actually living in much worse conditions than the so-called 'enslaved' ones, I'd certainly stop to question the definitions of 'enslaved' and 'free'.

Re: Philae has landed

#194

Post by mVChr »

ctdonath wrote: post #83
easytiger wrote: post #69

Earlier quoted context omitted.

Why does it need to anchor itself? It's not like it will blow away?

Gravity there is so low that something like a light push may be enough to launch. If anything used to examine the surface makes contact and presses (drill, digger), good-bye lander. Firing the harpoon would also be enough to launch, but at least the hook would grab the surface and pull the lander back down, giving enough pull to drill viable long-term anchors.

Are there any forces in effect as it gets closer and swings around the sun that might cause it to separate from the comet if there is no further attachment by then?

Re: Philae has landed

#195

Post by jafaku »

ajuc wrote: post #116
throwit99 wrote: post #94

Earlier quoted context omitted.

At the risk of turning political, it's a great example of how our taxes are wasted. Playing with space toys shouldn't be funded with taxpayer money. I'm sure I'll get downvoted to hell for this, but why should my money be funding this? Sorry, but it has no benefit whatsoever. edit: Instead of downvoting a dissenting voice, why not argue your case - why should taxpayers fund space toys? edit2: Well, looks like I'm ban…

Roseta mission is 1 400 000 000 euro. London summer olympics costed almost 10 000 000 000 euro. Consider the benefits. Landing on comets and knowing what materials are there (and how to detect that from distance) will eventually let humanity explore solar system. In next 10000 years it's almost sure there will be at least one global cataclysm (huge asteroid impact, ice age, global warming, methane-producing bacteria…

How can one care about what will happen within the next 10,000 years?

Re: Philae has landed

#196

Post by JoeAltmaier »

mVChr wrote: post #194
ctdonath wrote: post #83

Earlier quoted context omitted.

Gravity there is so low that something like a light push may be enough to launch. If anything used to examine the surface makes contact and presses (drill, digger), good-bye lander. Firing the harpoon would also be enough to launch, but at least the hook would grab the surface and pull the lander back down, giving enough pull to drill viable long-term anchors.

Are there any forces in effect as it gets closer and swings around the sun that might cause it to separate from the comet if there is no further attachment by then?

Absolutely! If its attached, its via surface ice. That ice will all melt on close approach to the sun. At some point the probe will drift away.

Re: Philae has landed

#197

Post by masklinn »

32faction wrote: post #76
masklinn wrote: post #65

Earlier quoted context omitted.

It did land, here's the next tweet: > It looks like @Philae2014 made a fairly gentle touch down on #67P based on amount of landing gear damping #CometLanding but the harpoons may have failed to fire.

land =/= secure. those harpoons are what is supposed to anchor Philae to the comet. the problem is the reaction thruster, the thruster that counteracts the force generated by the harpoon shot, (to satisfy Newton's 3rd law) is faulty. So they're hoping that when they reshoot the harpoon, the foot screws will be anchored enough to hold it in place. If not, theyre hoping that Philae won't launch too far off the surface…

> land =/= secure.

And I replied to a comment which said "land".

Re: Philae has landed

#198

Post by pbhjpbhj »

ITT downvoting to invisibility because you disagree with someone honestly held and cogently expressed opinions.

Silencing diverse opinions is quite possibly the worst facet of HN.

Re: Philae has landed

#199

Post by tedks »

bennyg wrote: post #124
throwit99 wrote: post #114

Earlier quoted context omitted.

So effectively, you want to subsidise scientists working on some arbitrary aim (Space exploration), in the hope they'll invent cool stuff you can spin off... I don't think you need to subsidise science like this. Did we really get "propelled" into new age of technology half a century ago? Did the moon landing really change anything here on earth? Technology would have advanced just fine without it.

What other arbitrary aims would you rather scientists work on, since all aims are arbitrary anyways? I don't think you really understand how scientific research works at all. The engineering effort of NASA took a bunch of disparate scientific discoveries and pieced them together to land humans on the moon. Don't tell me you don't think that sparked major economic development in this country for decades. One of the la…

Well, presumably if NASA is good because it produces things that can be spun off, you could just put the money into directly producing the spinoffs (somehow) and be more efficient.

>The entirety of humanity has been involved with exploring our curiosities. Exploring our curiosities tends to lead towards societal/scientific progress. Space is one of those.

I think this is almost certainly false. Very little of humanity has been involved with exploring any curiosity. Go to a third-world village and see how much curiosity is being explored.

It's also disingenuous to claim that NASA is some grand scientific curiosity mission. NASA is part of the military-industrial complex and operates as a slightly more palatable alternative to designing ICBM's directly. This is sort of like how mathematicians work for the NSA studying problems that are sanitized to be unrelated to the actual problem the NSA is trying to solve. It's a modern, scientific equivalent of a blank round in the firing squad.

Personally, I think that space exploration is a good thing because having all your species-level eggs in one planetary basket is a bad idea, but these are not compelling arguments in favor of space exploration, and they don't stand up to very easy to form arguments.

Re: Philae has landed

#200

Post by tim333 »

bsaul wrote: post #17

Anyone knows where i could find some info about the software stack this kind of probes are being built with ? Languages, programming methods, patching methods,os, runtime, etc. I'm really curious to know how different it is from the web or enterprise development worlds.

There's some discussion here, written by Attila Baksa who according to his linkedin is "Designer and developer of flight software of On-board Computer of the Rosetta Lander of ESA, which was successfully launched in 2003 and arrived to comet P67 in 2014."

eg: "The on-board software of the central computer of the Philae Lander consists of a real-time operating system and 8 application tasks. All these software modules are specially developed by our team for the Harris RTX2010RH microprocessor. The co-ordination of the scientific program and the overall control of the algorithms used by the application tasks are done by the MSO modelling language."

http://www.hiradastechnika.hu/data/upload/file/2004/2004_12/...

Also the "scheduling system, called the Rosetta SGS Scheduling Component" is discussed here:

https://ai.jpl.nasa.gov/public/papers/chien_iwpss2013_schedu...

which uses a framework called APSEN written by NASA:

http://aspen.jpl.nasa.gov/

which takes code like this:

Activity prevalve removal {

duration = 15

slot subsystem

after prevalve prep with (subsystem == this.subsystem)

before prevalve replace with (subsystem == this.subsystem)

Reservation hydraulic lift usage {

resource = hydraulic lift; usage = 1;

duration = 5;

requires state prevalve-purged TRUE

requires state prevalve-illuminated TRUE

 to control the thing

http://metahack.org/isairas97-aspen.pdf

Post reply on HN