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Pioneer Anomaly Solved By 1970s Computer Graphics
Frans Faase updated us on a Pioneer Mystery we've been following for many years: something is tugging Pioneer 10 & 11. A few years ago a theory surfaced but now "A new computer model of the way heat is emitted by various parts of the Pioneer spacecraft, and reflected off others, finally solves one of the biggest mysteries in astrophysics. Previous calculations have only estimated the effect of reflections. A computer modeling technique called Phong shading was used to work out exactly how the the emitted heat is reflected (PDF) and in which direction it ends up traveling. Taking into account the reflections on the antenna seem to make the anomaly disappear."
So it seems, the mystery ain't a mystery after all... No more hookum about some "unknown" force. Glad to know.
The technique for Phong Shading was introduced in 1973 as an improvement to Gouraud Shading, but was too computationally intensive to be used for graphics back then. This is no longer the case.
How does it feel to be a liar with pants constantly on fire?
Oh, well. It was fun while it lasted.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
everybody knows that. A much better aproximation to real life surfaces are the Oren–Nayar or Cook-Torrance models of the family of BRDFs.
Experiments and other stuff
Instead why don't they solve the radiosity equation at a 1 mm^2 resolution? That should be feasible with today's computing power, and indisputably give the correct answer.
But how exactly is heat contributing to this? Unlike most Slashdotters, I'm no self-professed rocket scientist. My understanding of space propulsion is that you throw some mass in the opposite direction of the one you want to travel in
... from Slava Turyshev which describes what they did to model the craft and show that heat could be the culprit.
http://www.planetary.org/programs/projects/pioneer_anomaly/update_20080519.html
Intron: the portion of DNA which expresses nothing useful.
I take this to mean they've finally received contact from Nibiru.
Fucking Phong Shading. How does it work?
<xml><I><am><so><damn>Web 2.0</damn></so></am></I></xml>
Janus is pulling them!
(just finished Pulling Ice. I'm sorry.)
Trolling is a art,
if it weren't for you meddling kids!
Radiosity being a 90s computer graphics term for calculation how radiation (heat and light) hit surfaces and are absorbed or re-emitted by them. It came from earlier studies on this not relating to computer graphics.
You can render your radiosity results using phong shading or other shading techniques.
http://lkml.org/lkml/2005/8/20/95
Imagine how well you'd model this using monte-carlo techniques / ray tracing.
Poorly when compared to Cook-Torrence, Blinn or Oren-Nayar.
I RTFA, but didn't find the results of their calculation. The old method yielded 67% of the effect, but they didn't say what the new method resulted in (other than get the "right" answer). Also I'd want to know error bars. Does the new answer +/- error bars overlap with the detected phenomena within the error bars of it's value?
http://en.wikipedia.org/wiki/Radiometer/
http://www.eclipse-chasers.com/tseAllias.html
When you're this old, let's just see how your probe looks in a phong!
I remember Phong as a rough approximation for some simplistic lighting models and surfaces.
For this anomaly, wouldn't someone be able to do a nice monte carlo simulation and get results as accurate as they want to establish a picture of the steady state conditions? They should be able to model the entire space craft including original heat source(s), other structures acting as thermal masses, reflectors, absorbers, and radiators, and apply known material properties for how each photon should behave statistically.
Or is it necessary to solve computationally using only 1970s vintage equipment?
Phong? Whew, that was what we used to use on Macintosh Infini D version 1.0 in the early 90s because the IIc was so slow. You would have thought they would have Ray Trace with Radiosity by now :o) ...
The purpose of existence is to make money.
Then you have to read it better, IMHO.
Does the new answer +/- error bars overlap with the detected phenomena within the error bars of it's value?
If you read the paper itself, there's a graph on page 10 showing exactly that. The error bars on the measured size of the effect overlap almost completely with the error bars on this new calculation.
Direct thermal radiation off the front of the craft explains most of the effect. The "Pioneer anomaly" vanishes completely once you factor in radiation reflected off the antenna dish. It still warrants some more investigation and more papers pinning it down better, but in my opinion this issue can now be pretty solidly categorized as resolved.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
And now, let's solve the "Flyby Anomaly".
FTA: "These results account for between 44% and 96% of the reported value". Note: that quote is cherry-picked; if you want all the details, RTFA.
Your malicious disregard for basic communication makes me want to side with Hairyfeet on principle alone.
Also, you should know that I am a little embarrassed that I took the time to 6 posts in the thread you linked. The fact that you seem to have an encyclopedic knowledge of every post you've ever made here leads me to believe you take the goal of winning at internet way to seriously.
See subject: Especially since it's from one of HAIRYFEET's many trolling accounts (& IF you don't think that goes on here? Please... see the words of someone VERY respected on THAT account):
It just takes one Ubuntu sympathizer or PR flack to minus-moderate any comment. Unfortunately, once PR agencies and so on started paying people to moderate online communities, and to have hundreds of accounts each, things changed. - by Bruce Perens (3872) on Friday July 30 2010, @04:55PM (#33089192) Homepage Journal
So, do you *THINK* you're really "fooling anyone" Hairyfeet?
(LMAO - "NOT!")
APK
P.S.=> TO this, I will tell you EXACTLY how I do it (born that way, near photographic/eidetic memory):
"The fact that you seem to have an encyclopedic knowledge of every post you've ever made here leads me to believe you take the goal of winning at internet way to seriously." - by tophermeyer (1573841) on Thursday March 31, @04:11PM (#35682048)
Comes in handy when trolls like Hairyfeet screwup & troll me, which he did 1st to me this week, attempting to libel me... & that same memory brought up what VINDICATED me as well, easily... thank the good lord, I say! apk
Comes in handy when trolls like Hairyfeet screwup & troll me,
But probably not too helpful in talking to people.
APK, who are you? I apologize for my ignorance, but I'm not certain who you are and why people would seek to defame you. You should know that your anonymous postings and disjointed writing style make you seem less "persecuted intellectual" and more "schizophrenic homeless dude under a bridge".
He is a known troll and malware writer who follows around and trollbombs anyone who points out that even simple math shows his "invention" doesn't work.
There is a reason why everyone abandoned HOSTS files in the late 90s, and that is because they slow your PC down while giving NO protection from malware. it is simple math really, you have a large (estimates at 1.5 million+) dynamically shifting target, where sites become infected, cleaned, reinfected, thousands by the day, sometimes thousands by the hour, yet this loon is convinced that a static HOSTS file will magically protect you from malware.
Sadly this person is also a paranoid schizophrenic with a serious persecution complex who will follow you around, sometimes for months on end, so he can "trollbomb" any posts you place while calling anyone who doesn't join his AC sockpuppet army a "shill post" or a sockpuppet, while quoting from people that frankly wouldn't piss on him if he was on fire like Bruce Perens, and then quotes them in completely unrelated matters to boot.
So don't be surprised if Crazy Petey follows you around for a few days friend, you dared to say something that goes against his "I'm a leet hacker that everyone fears!" delusion, just as I have been followed off and on for months, with everyone that points out what a batshit loonie Petey is being accused of being part of some vast super HB Gary sockpuppet army controlled by me and the Illuminati. I used to think the guy was just a Twitter style troll, now sadly I think he seriously needs some help. It is a shame nobody can track this guy down and do an intervention, as just from his writing style you can tell he is coming off the rails.
ACs don't waste your time replying, your posts are never seen by me.
http://www.facebook.com/topic.php?uid=254000146591&topic=16411
That is a copy of this site that seems to have gone offline recently:
http://www.suppressedscience.net/
Suppressed? :-) At the very least by marketplace forces? :-(
See also:
http://replay.waybackmachine.org/20090308132014/http://suppressedscience.net/physics.html
http://replay.waybackmachine.org/20090309114648/http://suppressedscience.net/
Stuff I wrote building on those ideas:
http://www.pdfernhout.net/to-james-randi-on-skepticism-about-mainstream-science.html
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
I don't remember Pong having any shading, just a black screen with white rectangles!!!!
Sure enough, the cow costume was hanging up next to the superhero outfit and sailors uniform. (S,Spud)
Aw crap! I was hoping the anomaly might point to a new physical effect that could be used to make warp drive or something
Wow, man somebody is on the ball at Wikipedia. Inertia is one of my favorite topics and somebody has already corrected this entry which used to say:
http://en.wikipedia.org/wiki/Inertia
Source of Inertia
There is no single accepted theory that explains the source of Inertia. Various efforts by notable physicists such as Ernst Mach (see Mach's principle), Albert Einstein, D Sciama, and Bernard Haisch have all run into significant criticisms from more recent theorists. A review is given by Vesselin Petkov (2009)[12].
For a recent treatment of the issue see C. Johan Masreliez (2006)[13]. Masreliez has published more on inertia related issues that may also have a say in solving the Pioneer anomaly.