Argylas

Guys, Has anyone heard anything about this? - http://gizmodo.com/part-of-a-rocket-engine-landed-in-this-guys-living-room-1727544878 Is it real or is this some media trying to create a story out of nothing? I shudder to think what its like to have an enormous rocket engine embed itself on your sofa next to you while you watch TV or something. That's what I call a dramatic entrance:) Very Kerbal, much like. On a more serious note its good that there are no casualties...

It is my opinion that if we are replaced by our machines, then we have not "failed" as a species. On the contrary - we have produced "offspring" that are even better adapted to their environment (humans are not adapted to living in space, while our machines may be). Saying that to be replaced by our machines is a "failure" is a complete lack of understanding of how life works. Our machines will be just as much alive as us, even if they are made of different materials like metal. And who says they will be made of metal - we will probably be able to build "machines" out of organic matter in the future. In my view homo erectus did not "fail" as a species because they were supplanted by homo sapiens, as homo sapiens are their "offspring" specie. It should be the same with us and our machines - the fact that evolution in this case will not be random and carried over through the DNA mechanism is irrelevant. It is evolution nonetheless.

As Bill Phil said there's no real distinction between technology and biology - it is only in our heads. Biology is still a way to turn energy into useful work, just as technology. It just turned out that nature had some organic material laying around and "made" life out of it. If it was more advantageous to use iron or something similar, we would have been walking metal robots instead of blobs of organic matter and water. That being said, "biology" as you call it, thanks to billions of years of evolution, is far, far ahead of technology right now. Each cell, every neuron, every muscle in our bodies is a finely tuned machine or computer, geared at doing its job incredibly well. Just think of how complex an organ the eye is and what it is capable of doing. We can't reproduce its sensitivity or complexity using current technology. We can make instruments that can be more well-suited for a particular situation, but we cannot make something that does everything the eye is capable of in a better way. The same goes for almost every organ in our body. And when we move to microscopic level - our cells, our hormones, etc. - humanity's efforts to emulate "biology" are even more pathetic at the moment. The reason most people think there is some inherent difference between "biology" and "technology" is because we can make machines that are better than us in specific tasks. However, living organisms were "designed" (for a lack of a better word) with a different goal - to survive at all costs. Humans (and all living things) are able to receive useful information from numerous stimuli, to interpret this information and to act on it in order to survive. And for that to happen living things are equipped to deal very well with everything that comes their way in their habitat. Which is orders of magnitude more complex than anything technology can do today. Given some centuries of continued technological progress and we may get there. I say "may", because the complexity of life is so big that the task of emulating it gargantuan and unquantifiable - it may take us decades, it may take us centuries or even thousands of years. So to summarize - if in the future we develop "technology" (with which I assume the OP means things made of "artificial" stuff like metal or silicon) and meet a hostile civilization, which has developed "biology" (which I assume the OP means things made out of organic matter) AND both species at a relatively similar progress level, I think there would not be any difference. To use the OP's example - if we shoot missiles at them, they may heal the damage using organic molecules or whatever. If they shoot organic explosive pods (peashooter for teh win! at us, our ships will heal the damage using microscopic nanobots, which will use available surplus material to mend the holes in the hulls. So to summarize - at similar progress levels "biology" and "technology" are the same thing. Only the source material everything is made of is different (metal & plastic vs. organic matter). And this doesn't give a particular advantage to any side.

NASA needed close to $ 200 bln. for the Apollo program (accounting for inflation since the '60s). That is close to $ 20 bln. per mission. Even if SpaceX somehow reduces this cost through exploiting know-how from the Apollo landings, rocket reusability or what have you, they won't bring that price too much down. SpaceX's revenues are kept secret by Musk, but according to private companies-researcher "PrivCo" they were over $800 mln. in 2014. Let's say 30% of that or $240 mln. are profits (a bit unrealistically high, but let's let it slide for the sake of the argument). So, SpaceX will have to save all of its profits for close to 70-80 years (barring any dramatic growth in its revenue - orders of magnitude type of dramatic) to be able to afford even one mission to the moon. And they will need a lot more missions in order to send a spacecraft to the moon - test flights, etc. So you see how incredibly unrealistic such a mission is. It just impossible economically for any given single company. Even Bill Gates will have to spend ALL of his fortune to fund just one moon mission (because his reported wealth of $ 60-70 bln. is not in liquid assets and if he sells it all at once - shares, real estate, everything - his true net worth in real hard cash will be closer to $ 20 bln. or even less). Oh, and a mission to Mars will probably cost a lot more. So the sad truth is manned missions beyond LEO are still unfeasible for companies and individuals. Like it or not, manned spaceflight is still within the capabilities of only the wealthiest nations (and they currently lack any political will for bold missions). Let's hope there is some incredible technological advancement in the near future that will make manned spaceflight more affordable (and I don't mean rocket reusability - it won't be enough by far).

"The researchers were able to take detailed images of the insects without harming the creatures, Hariyama said, adding that almost all of the insects in the study survived the imaging." It seems insects can survive without breathing for as long as it takes to image them with this technique. Possibly the researchers remove the coating from the specimens afterwards...

But wouldn't the fact that structured photons are slower than normal ones in vacuum change the way we look at the universe? If there is a way in nature to produce coherent light (that is structured photons), then we may have to rethink what we are seeing in the universe, or more exactly, how far back in time are we seeing things. Imagine a star 100 000 light years away can emit coherent light and we only see these structured photons. We presume they have traveled to us with a speed of c, but they may have been slower, making us see the star as 101 000 light years away. I don't have much knowledge in the field of lasers and optics, so I have no idea if anything like this is even remotely possible, but if it is, this may turn out to be a significant discovery.

I was wondering what the more knowledgeable people on this forum have to say about this - http://www.businessinsider.com/speed-of-light-isnt-constant-2015-1 Is this paper credible? And if we really can change the speed photons travel at permanently what are the implications of this?

Oh boy. Prepare for a long read. I really am a bit pessimistic every time someone mentions the Drake equation as a proof that the universe must be teeming with life. Intelligent life nonetheless. However, what bugs me the most is that people always look at just one part of the equation - the one about how many planets, stars and galaxies are there in the universe. Yes, the number is mind-boggling. Yes, in all practical terms it almost verges on infinity. However, what about the parts in Drake's equation about "the average number of planets that can potentially support life per star that has planets" and "the fraction of planets that could support life that actually develop life at some point"? We have no proof whatsoever that life-supporting planets are abundant. Yes, we know life can continue to thrive in extremely inhospitable places - like in extreme heat, extreme cold and even survive in the vacuum of space. But what if in order for life to start there must be a very narrow and specific set of circumstances present? Like for example if the tilt of the Earth was off by a millionth of a degree less, life could not have originated here at the time it did? Or if the distance of the Earth to the sun was with a couple of hundred kilometers less, this would have made the originating of the precursors of living microorganism impossible? No one can give even a guesstimation what are the chances for a planet to have just the right circumstances to allow for life to originate on it. We have only one instance of this happening we know of and this isn't statistically viable to predict anything. Some estimates for the number of stars in the universe put them at at least a quadrillion stars (that's one with 24 zeroes behind it). But what if the chances of having a planet with just the right conditions to originate life (which may be way smaller than just being habitable) and having life actually originate there are less than one in a quadrillion? Then we are screwed big time. Now, I may sound pessimistic, but I just wanted to warn against overestimating the chances for life in the universe based only on the part of the Drake equation we know something about. Until we find extraterrestrial life we can't even begin to fathom what the number of life originating planets in the universe are. Hopefully its big and we soon find signs of life on Mars, Titan or Europa (or somewhere else). Also, what if there is life around us, but we simply cannot realize it is there? We still don't have a very good understanding and definition of what living matter actually is and what differentiates it from non-living matter. And we continue to find organisms and particles that stretch our imaginary divide between the two (like viruses and many others). What if the differences between us and the aliens are temporal? Like if there is life on Mars, but its looks like a pile of rocks and it takes tens of thousands of years for it to make a simple movement (having a life span of millions of years for example)? We would never notice it is alive. Or what if its scale is just too big for us to comprehend - like a solar system, which is "alive" and intelligent, but its thoughts are minute variations in the orbits of the planets orbiting its sun, which we cannot even detect? These are all great ideas for sci-fi fodder, but the truth is we can't even begin to imagine the possibilities. So these are two of the reasons the little green men have not visited us yet. Others include the small area of space we have reached around us, the possibility aliens are avoiding detection intentionally, etc., etc. However, I somehow think they are less likely than the ones stipulated above. I really, really hope there's intelligent life out there we can comprehend and detect in our stellar vicinity. However, I prefer not to get my hopes too high before we receive any definitive proof that such a thing exists.

Just a quick thought - will any future manned spacecraft that goes to Mars use aerobraking to save delta-V for circularising or is it far too risky/requires too much added weight for heatshields? I used this all the time in KSP, but when I started using the Deadly Reentry mod I found that suddenly I was much more inclined to chalk up the increased delta-V cost to just circularize around the planet I just wondered if it is the same in RL and whether NASA has even considered using aerobraking as a possible scenario for orbiting Mars.

I've tried to find a current map of the Milky Way or at least a small part of it, but to no avail. That is why I wanted to ask if someone here has stumbled over something like this. Let me clarify - I don't mean a map of our galaxy as we observe it right now, as this would only be a collection of snapshots from the past (depending on the distance of each star to us). What I want to find is a map of some part of the galaxy, in which the position of all objects is extrapolated to their current coordinates. I know this requires a very difficult model simulation, but someone somewhere should have done it at least for the local group of stars near our Solar system. As all star orbit the center of the galaxy and have different velocities and orbits, they should be changing their position with regards to our sun. So even a star as close as Procyon (~ 11 light years) should be in a different position with regards to the Solar system 11 years from what we see today. I know they have done it for the movement of the Andromeda galaxy and have seen that it will collide with the Milky Way in about 4 bln. years. So it should be doable. So if you have come upon something similar to what I am searching for, I would be deeply gratified if you share it with me.

"Not bad for a navy guy"

Hi, I'm sorry if this has already been posted on the forum, but I recently found a very interesting new theory by Jeremy England - an assistant professor at the MIT, about why life exists. You can read an article about his theory here - https://www.quantamagazine.org/20140122-a-new-physics-theory-of-life/ Basically his theory, as far as i can understand (and I'm not a scientist by any means) is that the creation of life in a given system is inevitable, because life turns out to be the most efficient mechanism of increasing entropy in an "open" system. I would generally feel very skeptical about such "groundbreaking" theories, but this one resonates well with my strong (but not based on any true scientific facts) belief that there is no or at least very little distinction between living and non-living matter in the grand picture of things and that our anthropocentric view of the universe is what makes us classify these two things as inherently different. I would be glad to hear the opinion of people here with a better scientific background than me (which would probably be more than 90% of you) on this theory and whether it really presents a new promising train of thought for biochemists to consider.

When you design a SSTO in FAR with the aim to launch a 14400 full fuel tank into space for refueling purposes, and then realize that you can launch it straight up without a gravity turn and it could still make an orbit close to the one of Minmus.... and then land safely back at KSC. With the full fuel tank still attached.

Sadly I think the only reason for the existence of the North Korean space program is to develop a reliable ICBM to carry any nukes they have. This will increase their threat level to the West and in their leaders' eyes make them more powerful on the international scene.

If they really made some breakthrough (and that is a VERY big if) and have a concept for a net energy-gain fusion reactor with the size of a truck, this will revolutionize a lot of industries. It will turn the energy sector on its head. And we will have fusion powered airplanes and spacecraft in the future. One can only dream...