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How sure is the information that a human body would not completely burn / ablate during atmospheric re-entry? I am not aware of any material ground tests in a plasma wind tunnel confirming that human tissue would survive re-entry from LEO.

Since a steak would not even be cooked by dropping it from very high altitudes (http://what-if.xkcd.com/28/) I would doubt that a space tourists body would desintegrate by atmospheric re-entry.

Funny link, however, some things are not clear enough: 1. Ablation rate is unknown 2. What are the entry conditions? The link suggests that the steak is just dropped (no initial velocity). 3. What about the ballistic coefficient? 4. How would the entry body orientation? It would be a quite non-steady state configuration I guess with heavy accelerations. 5. How would vacuum exposure impact on the water in the body/steak and what would be the consequence for ablation behaviour? 6. Does surface chemistry play a role (not ablation, but catalysis)? My conclusion: the example with the steak is a funny and not so bad exercise, not more.

As you can see from the videos of this meteorite it is coming in from an east to south-east direction (i.e. the direction of the sunrise, more or less). 2012DA14 is coming from due south as you can see here: http://www.wired.com/wiredscience/2013/02/how-to-watch-asteroid-2012-da14/ So the two objects seem to be coming from different directions - at least that would be my explanation.

My point is, that if you want to come to such a conclusion (that it is not rubble) you need to be able to construct back the orbits of both objects. 2012DA14 has been observed for one year only, but it is well enough. When the meteor has been observed for the first time, such that we knew its orbit? has it been observed before? if yes, why the impact has not been predicted?

If you can show that they come from different directions you know that they are not associated, even if you don't reconstruct their orbits.

I don't think so. If both objects were part of the same, they would be on different but intersecting orbits anyway, hence different directions. Anyway, I am not knowledgeable in atmospheric entry ... But, with so few information about the object, I am surprised they are 100% certain it is not related to DA14. I think science requires more cautions ... With only the direction they are 100% sure, while the probability of such event is itself extremely small, I am amazed... They can't even predict with 100% certainty where a space debris will fall... plus, nobody consider the object being part of a bigger one that broke up during early entry (which has not been observed) ... so many uncertainties and possible hypothesis... and i am not the only one :) http://www.infowars.com/russian-meteor-linked-to-da14-asteroid/

was not that evident to me also but apparently with the right understanding it was quite clear; was amazed also how quickly NASA has published the likely trajectory of the russian object - have a look at it: quite evident that these are not coming from the same body

Jo, thats just brilliant... 500billion USD total on advertising, that sounds absolutely ridiculous.. I always wondered whether this giant advertisement scheme is just one big 'ponzi'-like scheme waiting to crash down on us one day when they realize, cat-picture twittering fb-ing whatsapping consumers just aint worth it..

"Kurzweilians"... LOL. Still not sold on embodiment, btw.

The biggest problem with embodiment is that, since the passive walkers (with which it all started), it hasn't delivered anything really interesting...

The problem with embodiment is that it's done wrong. Embodiment needs to be treated like big data. More sensors, more data, more processing. Just putting a computer in a robot with a camera and microphone is not embodiment.

I like how he attacks Moore's Law. It always looks a bit naive to me if people start to (ab)use it to make their point. No strong opinion about embodiment.

@Paul: How would embodiment be done RIGHT?

Embodiment has some obvious advantages. For example, in the vision domain many hard problems become easy when you have a body with which you can take actions (like looking at an object you don't immediately recognize from a different angle) - a point already made by researchers such as Aloimonos.and Ballard in the end 80s / beginning 90s. However, embodiment goes further than gathering information and "mental" recognition. In this respect, the evolutionary robotics work by for example Beer is interesting, where an agent discriminates between diamonds and circles by avoiding one and catching the other, without there being a clear "moment" in which the recognition takes place. "Recognition" is a behavioral property there, for which embodiment is obviously important. With embodiment the effort for recognizing an object behaviorally can be divided between the brain and the body, resulting in less computation for the brain. Also the article "Behavioural Categorisation: Behaviour makes up for bad vision" is interesting in this respect. In the field of embodied cognitive science, some say that recognition is constituted by the activation of sensorimotor correlations. I wonder to which extent this is true, and if it is valid for extremely simple creatures to more advanced ones, but it is an interesting idea nonetheless. This being said, if "embodiment" implies having a physical body, then I would argue that it is not a necessary requirement for intelligence. "Situatedness", being able to take (virtual or real) "actions" that influence the "inputs", may be.

@Paul While I completely agree about the "embodiment done wrong" (or at least "not exactly correct") part, what you say goes exactly against one of the major claims which are connected with the notion of embodiment (google for "representational bottleneck"). The fact is your brain does *not* have resources to deal with big data. The idea therefore is that it is the body what helps to deal with what to a computer scientist appears like "big data". Understanding how this happens is key. Whether it is the problem of scale or of actually understanding what happens should be quite conclusively shown by the outcomes of the Blue Brain project.

Wouldn't one expect that to produce consciousness (even in a lower form) an approach resembling that of nature would be essential? All animals grow from a very simple initial state (just a few cells) and have only a very limited number of sensors AND processing units. This would allow for a fairly simple way to create simple neural networks and to start up stable neural excitation patterns. Over time as complexity of the body (sensors, processors, actuators) increases the system should be able to adapt in a continuous manner and increase its degree of self-awareness and consciousness. On the other hand, building a simulated brain that resembles (parts of) the human one in its final state seems to me like taking a person who is just dead and trying to restart the brain by means of electric shocks.

Actually on a neuronal level all information gets processed. Not all of it makes it into "conscious" processing or attention. Whatever makes it into conscious processing is a highly reduced representation of the data you get. However that doesn't get lost. Basic, low processed data forms the basis of proprioception and reflexes. Every step you take is a macro command your brain issues to the intricate sensory-motor system that puts your legs in motion by actuating every muscle and correcting every step deviation from its desired trajectory using the complicated system of nerve endings and motor commands. Reflexes which were build over the years, as those massive amounts of data slowly get integrated into the nervous system and the the incipient parts of the brain. But without all those sensors scattered throughout the body, all the little inputs in massive amounts that slowly get filtered through, you would not be able to experience your body, and experience the world. Every concept that you conjure up from your mind is a sort of loose association of your sensorimotor input. How can a robot understand the concept of a strawberry if all it can perceive of it is its shape and color and maybe the sound that it makes as it gets squished? How can you understand the "abstract" notion of strawberry without the incredibly sensible tactile feel, without the act of ripping off the stem, without the motor action of taking it to our mouths, without its texture and taste? When we as humans summon the strawberry thought, all of these concepts and ideas converge (distributed throughout the neurons in our minds) to form this abstract concept formed out of all of these many many correlations. A robot with no touch, no taste, no delicate articulate motions, no "serious" way to interact with and perceive its environment, no massive flow of information from which to chose and and reduce, will never attain human level intelligence. That's point 1. Point 2 is that mere pattern recogn

could we just use genetic algorithms to evolve these shapes and layouts? :P

> Not sure if the skycrane is really necessary but it is certainly cool. I think apart from coolness using a skycrane helps keep the rotating knives away from the recipient...

Honest question, are we ever going to see this in practice? I mean besides some niche application somewhere, isn't it fundamentally flawed or do I need to keep my window opened on the 3rd floor without a balcony when I ordered something from DX? Its pretty cool yes, but practical?

Package delivery is indeed more complicated than it may seem at first sight, although solutions are possible for instance by restricting delivery to distribution centers. What we really need of course is some really efficient and robust AI to navigate without any problems in urban areas : ) The hybrid is interesting since it combines the advantage of a Vertical Takeoff and Landing (and hover), and a wing for more efficient forward flight. Challenges lie in the control of the vehicle under any angle and all that this entails also for higher levels of control. Our lab has first used this concept a few years ago for the DARPA UAVforge challenge, and we had two hybrids in our entry last year for the IMAV 2013 (for some shaky images: https://www.youtube.com/watch?v=Z7XgRK7pMoU ).

While Google and facebook are out: http://qz.com/422775/facebook-and-google-are-out-of-the-space-race/

reading the qz article, it is not clear to me that google dropped out as one of the main investors in SpaceX? did I miss something?

I attended a presentation by H. Hemmati, formerly at NASA's JPL, now at Facebook working to "connect the unconnected" during a panel session of the Workshop "Shining light on future space optical communications". I gather that they are targeting a combined strategy of HAP (with solar powered planes at 20-25 km), balloons and satellites. The rationale behind is that each solution is best suited for different population density zones, i.e. satellites while expensive (total cost of 100MUSD after Hemmati) are the only way to provide internet in remote zones, while balloons seem to be one inexpensive solution for densely populated areas. Funfact: he mentioned that the main drawback will be some crashes of HAP elements...

whoops indeed

sounds really bad ... how bad is it???

Heads will fall in ESRIN... And now I know who crashed my computations on sophia ;-) [Edit] A lesson for everyone: look at the file with email passwords and see how many you are able to guess even though they're supposed to be scrambled by removing a middle part... [Edit] And a hilarious quote from the hacker's "about me": "I had another blog, more exactly www.tinkode.baywords.com but I forgot the password, so now I created this one."

got the reply from IT security today: they had dealt with apparently the very same day and all under control :-)