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Comment: Re:Fermi's paradox is hubris (Score 1) 142

by Lumpy (#48922311) Attached to: Gamma-ray Bursts May Explain Fermi's Paradox

That a similar setup pointed at the exact location can detect. guess what, that doesn't work well even here on the planet. Point to Point Dish based directed communication is a bitch to get working in insanely small distances like only 10 miles. So we shoot a signal at a single cluster, did we do it for years on end? nope. so nobody will hear anything.

What you have to do is a wide insane power broadcast to cover the entire sky. Broadcast 24/7 for 10 years. That way not only do you have information you sent, but we even encode doppler information about our planet and sun.

Yes for 10 years, 100 years would be better. Because you dont know when someone will be aiming an insane gain antenna in our direction.

Comment: Re:Fermi's paradox is hubris (Score 1) 142

by Lumpy (#48919949) Attached to: Gamma-ray Bursts May Explain Fermi's Paradox

We already are surpassing radio to become something that is undetectable in space. spread spectrum and low power communications is already common place in the Ham Radio community. with 2.5 Watts I can talk to 30 people around the globe using PSK31 or Wspr. My signal will not be detectable past the moon even on the best radio equipment made. High power broadcasting is a thing of the past and will rapidly disappear. Some of these new technologies will make communicating with our own space probes easier, but hellishly harder to detect as power levels can be reduced.

A very advanced species will not be broadcasting at 200,000,000,000 watts with AM modulation or CW... what can be detected at light year or more distances. they will be using things that are far more efficient and will not be detectable. Honestly the whole SETI project is not looking for ET's TV stations or regular communications, it's looking for an intentional ultra high power beacon that was sent for the only purpose of saying "WE ARE HERE" which even reduces the chances of it being successful even more.

For SETI to detect a signal from Alpha Centauri. IT would have to be 10,000X stronger than any transmission ever sent from earth and on a constant time year after year after year so that it can be detected.

Comment: Re:Not really. (Score 2, Interesting) 142

by Lumpy (#48919899) Attached to: Gamma-ray Bursts May Explain Fermi's Paradox

First, us humans prefer killing each other to science. This is a proven fact.
Second, humanity did not go from Horses to Nukes, a very very small percent of the population did it, those geniuses have everyone else standing on their coat-tails.

The next leap will be by a very small group that is significantly more enlightened than the rest of the 99.95% of the population. If those people are benevolent, then everyone enjoys the fruits. If they are not....... Well, things can go very differently.

Currently with how education is going, the general population is becoming more uneducated every year. WE do not glorify learning, but instead glorify morons that can carry a ball, or can sing a tune. And we Vilify in society those that do love learning and are very smart.

Honestly Humanity is a joke, almost a cancer. And if an advanced civilization stumbled across us, they would probably wipe us out to make the rest of the universe safer. We as a species love to hate others, we love murder, war, and control. WE thrive on hating those that are different or think or worship different.

Comment: Re:Hear Hear! (Score 2) 357

by Rei (#48917379) Attached to: "Mammoth Snow Storm" Underwhelms

Ah, Americans and their "mammoth snowstorms" - try living on a rock in the middle of the North Atlantic. You know what we call a snowstorm with gale-force winds and copious precipitation? Tuesday ;) Our last one was... let's see, all weekend. The northwest gets hit by another gale-force storm tomorrow. The southeast is predicted to get hurricane-force winds on Thursday morning.

Here's what the job of someone dispatched to maintain antennae for air traffic control services has to deal with here. ;) (those are guy wires)

Comment: Re:Visible from Earth? (Score 1) 120

by Rei (#48915031) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

A sun-like star is about 1 1/2 million kilometers in diameter. To blot out all light from such a star that's 10 light years away, a 0,75 kilometer diameter disc could be no more than 1/200.000th of a light year, or around 50 million kilometers (1/3rd the distance between the earth and the sun).

The brightest star in the sky is Sirius A. It has a diameter of 2,4 million km and a distance of 8.6 light years. This means your shade could be no more than 25 million kilometers away.

The sun and the moon both take up about the same amount of arc in the night sky so would be about equally difficult to block; let's go with the sun for a nice supervillian-ish approach. 1,4m km diameter, 150m km distance means it'd be able to block the sun at 800km away. Such an object could probably be kept in a stable orbit at half that altitude, so yeah, you could most definitely block out stars with the thing - including our sun!

Comment: Re:keeping station behind it? (Score 1) 120

by Rei (#48914773) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

It makes sense. We can radiate individual photons for thrust if so desired. We can move individual electrons from one position in a spacecraft to another for tiny adjustments of angle and position if so desired. It seems you're going to be much more limited by your ability to precisely track your target than by your ability to make fine adjustments.

I think a much bigger problem is going to be isolating standing waves from within the shielding material from distorting its perfect rim (with a shield that big and thin, there *will* be oscillations from even the slightest thrust inputs). You need to isolate the rim from the shielding. And you also need to make sure that you can have a rim that can be coiled up for launch but uncoil to such perfection in space.

Tough task... but technically, it should be possible.

Comment: Re:No (Score 3, Insightful) 120

by Rei (#48914527) Attached to: Proposed Space Telescope Uses Huge Opaque Disk To Surpass Hubble

I would presume that the bulk material in the inside has no need for accuracy, only the very rim. The question is more of whether you can have a coiled material that when uncoiled (deployment) can return to a shape with that level of accuracy. I would think it possible, but I really don't know.

I would forsee a super-precise rim with just a small bit of light shielding on its inside, deployed via uncoiling, and then attached to a much stronger, less precise uncoiled ring to which the bulk shielding material (and stationkeeping ion thrusters) are attached. The attachment between the two would need to provide for vibration and tension isolation (even the slowest adjustments in angle of such a huge, thin shield are going to set in motion relevant vibrations, you've got almost no damping - you want the structural ring to deal with those and not transfer them through to the precision ring). Not to mention that your shield will be acting as a solar sail whether you like it or not (unless you're at L2... but then your craft better be nuclear powered).

Your telescope behind it is going to need to do some real precision stationkeeping (either extreme precision on the whole spacecraft positioning, or merely "good" positioning of the whole spacecraft plus extreme precision adjustment of the optics within) . This means long development times and costs to demonstrate that you can pull it off before you actually build the shield. But I would think that also possible - just very difficult. If they take the latter route they could probably demonstrate that here on Earth, which would be a big cost-saver.

Comment: Re:Early fragmentation (Score 1) 478

by putaro (#48911929) Attached to: Ask Slashdot: Is Pascal Underrated?

I did most of my work on Unix before I started at Apple in '95. All of the new OS development was being done in C by then. I suspect that before most of the OS development had been done in 68K assembler, not Pascal. When the switch to PPC started, Apple needed a cross-platform systems programming language and Pascal was not it.

This article from '93 references how the industry mindset had switched to C/C++ and that pushed Apple.

https://www.schneier.com/essay...

One thing to remember is that at that time, both Macs and PCs were not very powerful machines and large applications were being developed for Unix workstations.

Comment: So it was the 1950's PATRIOT ACT (Score 5, Interesting) 282

Because short of the martial law of troops in the streets with body armor and M16's..... Oh wait... Our COPS have those now.
Well they dont have assult vehicles...... Wait....
Nor do they have grenade launchers...... Welll.....

So basically they have been planning on the shit we have today for decades?

Comment: Re:Wow .... (Score 4, Informative) 154

by Rei (#48906547) Attached to: Scientists Determine New Way To Untangle Proteins By Unboiling an Egg

It's a two-step process. The first is a chemical that dissolves the proteins (still in their "cooked" folding), and the second is some sort of centrifuge or similar (they don't go into details on the device in the article) that subjects the proteins to very high sheer strain, effectively mechanically unfolding them so that they can then relax back into their natural state.

Not exactly a spice you can sprinkle onto your steak, but still pretty neat. :)

Comment: Re:America is HUGE (Score 2) 253

by Rei (#48904027) Attached to: Verizon, Cable Lobby Oppose Spec-Bump For Broadband Definition

That just raises another issue - why are you services and utilities so unreliable in the US? Here in Iceland we get hurricane-force winds several times a year on average - I've had gusts over Cat 5 on my land. Winter isn't incredibly cold but is super wet (all precipitation forms), windy, and lasts a long time. Up at higher altitudes you get stuff like this (yes, those are guy wires... somewhere in that mass). I lived in the US for a long time and had an average of maybe two power outages a year from downed lines and such - sometimes lasting for long periods of time. I've never once had a power outage here that was anything more than a blown breaker in my place.

It's really amazing what you all put up with - your infrastructure standards are really low.

If I were a grave-digger or even a hangman, there are some people I could work for with a great deal of enjoyment. -- Douglas Jerrold

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