
Help find a bright object on Mars - ivoflipse
http://mathematica.stackexchange.com/questions/11819/help-find-a-bright-object-on-mars
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thaumaturgy
Not directly apropos, but the current best answer on that page is probably
good enough to have been worth money to NASA, and somebody just did it for
free because it was a neat problem to solve and they could.

This is probably my favorite thing about the internet.

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lifeisstillgood
Somewhere his boss is wondering what on earth that guy was doing all day.

Yet, he has demonstrated to a wide audience what good image processing and
lateral thinking can do, he has brushed up on a few parts of mathematica he
has not used this past quarter and the world is a little bit richer

A TED talk recently mentioned how robots are replacing us and we need to
manage a jobless future - this indicates how we might do it.

Plus, I cannot work out which is worse - that bits of metal are dropping off
the Rover. Or not ...

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alexsb92
Do you mind providing a link to the TED talk in question? Been thinking about
that kind of future lately, and was wondering what other people (who've
probably thought about it for longer) have to say about such future.

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wintersFright
One idea I came across a while ago is the idea of a 'national dividend'.
Basically everyone gets a base amount of money you could live off. If people
want to work harder and earn more money, they are free to. Unfortunately I
can't recall the book I read it in.

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marvin
I've heard this view before. It's what I have been saying for some time now:
With vastly increased wealth for the richest due to technological leverage,
what will need to be done is increased taxation, especially for the richest.
The taxes can be used to pay for a "dividend" system, which could for instance
be implemented through negative taxation up to a certain low income. We might
not be there today, but it is where we'll end up if automation keeps spreading
at the rate it has until now.

Norway almost de facto has a system like this already (through an incredibly
generous welfare system), but the only reason we are able to pay for it is
through the huge petroleum income.

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mturmon
I'm not sure if very tiny and close objects like this one are something anyone
has focused on. At the moment, the MSL team has so many very well trained
eyeballs that they don't need much automation of relatively high level tasks
like this one. After the initial 90 days, the team will shrink, and automation
will be more important.

Detecting objects in medium to long range Mars rover imagery is a problem that
has received a lot of attention, including systems that run _on board the
rover_.

The people who have pushed this the farthest are here:

<http://aegis.jpl.nasa.gov/>

Just a recognition algorithm is not enough. You also need to integrate
prioritization, planning (is it OK to pivot the camera to point in that
direction, do we have enough room to store the data, ...), and acquisition to
have a system that actually gathers quality data without sacrificing other
mission objectives. The described algorithm has been run on Opportunity.

The selling point for on board automation in this context is light time. By
the time you send the images back, analyze them, and upload a new command
sequence to take the data, you would have driven past the interesting rock. So
you have to do some things on board. Limited bandwidth also plays a role.

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flyinglizard
The next time some alien life form comes to earth and wants to destroy us for
all the pain and suffering we are causing each other, lets just point it at
this link.

It is by far the best example of "Why the human race deserves to exist" that
I've seen this week.

Edit: this guy is responsible for this as well:
[http://mathematica.stackexchange.com/questions/5676/how-
to-p...](http://mathematica.stackexchange.com/questions/5676/how-to-peel-the-
labels-from-marmalade-jars-using-mathematica/5695#5695)

Awesome stuff.

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mixmastamyk
Channeling Picard...

"We are what we are, and we're doing the best we can. It is not for you to set
the standards by which we should be judged!"

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eranation
This is why I both love and hate reading hacker news / stack exchange. On one
hand this is one of the most amazing posts I've seen and made me want to learn
Mathematica and image analysis, but on the other hand, it made me want to
learn Mathematica an image analysis. (which has no real connection to my day
job or side projects)

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minikomi
Interesting that one of the responders advises the asker to leave the question
open to garner stronger responses - in stark contrast to SO where quick
turnaround (by both parties) is strongly encouraged. Different models for
different communities.

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sidcool
I am a bit lost here as I am not at all familiar with image processing and the
Math behind it. Can someone please shed light?

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cshimmin
Basically, the accepted answered did something like this:

First, he noticed that the sand looks pretty uniform. You wouldn't be able to
tell one patch of sand from another. So he just picked a random 200x200px
square of sand.

Using this sample of sand, he analyzed the color distribution. Looking at it,
he decided the color of a given pixel of sand-sample can be modelled
reasonably well by assuming a random gaussian distribution (think bell curve).

Next, he assumed the _whole picture_ was sand. The black-and-white image at
the end is essentially a plot of the likelihood that the corresponding picture
in the original picture would have been a grain of sand, assuming the normal
distribution found earlier. Black means "very likely" and white means "not so
likely".

Since we argued earlier that any patch of sand in this picture is as good as
any other, all of the sand appears black. The rover, and crucially, the
foreign object, do not fit the modelled distribution, so they stand out in
stark contrast.

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Ozark
Without knowing what he's looking for the 200x200px square sample might
contain the foreign object, then it might never be found.

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Stefan_H
In that case, wouldn't the 200x200px square with the anomaly still be
highlighted as unique from the rest of the sand, since none of the sand would
match it?

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lifeisstillgood
Very nice

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phogster
A mod named "rm -rf" lock-protected the thread. That's a terrible username.
Can you imagine thinking you're logging into your account but the focus is
accidentally on a command line window?

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michaelkscott
Actually, you can't login any of the Stack Exchange websites with a username
and password. The only options are OpenID and an email-based StackExchange
login.

And the username can be changed any time, so anyone can change their username
(which is effectively a "display name") to 'rm -rf' at any time if they want
to, IIRC.

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kmontrose
Technical our email-based login is also OpenID;
<https://openid.stackexchange.com/> , we just hide the details.

And even more nitpicking-ly, our Facebook login is OAuth 2; not OpenID.

But yeah, there's no relation between user display names and their logins.

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sixQuarks
I would think NASA spotted that bright spot using an algorithm. Do they have
people staring at each photo looking for such small anomalies?

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vhf
NASA spotted that bright spot after deploying the scooping robotic arm for the
first time, after its first scooping.[1]

You can see the scoop full of sand very clearly on the images.

This kind of maneuver (sampling martian stuff) is certainly crucial for
Curiosity's mission. You would guess that they were watching this first very
carefully, with a lot of engineers, scientists and attention. All of this
makes me think that they spotted this bright thing with bare eyes.

[1]
[http://www.nasa.gov/mission_pages/msl/multimedia/pia16225.ht...](http://www.nasa.gov/mission_pages/msl/multimedia/pia16225.html)

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drivebyacct2
How can these sorts of problems be posed to a wider audience?

Is NASA and SpaceX's work so narrowly defined that the community could not
help in other ways?

How great would that be? Get great industry minds involved in government work
furthering the space program and encouraging open source spirit all the while?

