Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SETI@home shuts down after 21 years

bleepingcomputer.com

Post reply on HN
Print view View original

181–190 of 356 posts

Re: SETI@home shuts down after 21 years

#181

Post by cletus »

schoen wrote: post #123
cletus wrote: post #80

Not to sound like a broken record (I and others have said this or similar on these kinds of threads) but... I, personally, have become convinced that looking for signals this way is actually pointless. The argument is basically this: 1. Within 1000 years (and maybe a lot less) we will have the engineering capability to build space habitats, powered by solar power. This last part is important because this thought expe…

> Even if it was, no known or currently theorized material could support this. Which physical limits are most relevant to precluding the solid sphere? Tidal forces?

So if we step back a second, look at a Ringworld. I'm not sure if Larry Niven proposed this idea (in the book by the same name) or just popularized it, but the idea is basically this: If you take the mass of the Earth and turn it into a ring that encircles a star, spin it to create artificial gravity and put walls on the sides (on the inside) to keep an atmosphere in.

What do you have? The same mass of Earth will have a million times the living area.

What's the problem? At 1 AU distance, this thing would have to spin so fast (IIRC ~1.5 million km/h) that the centrifugal forces would tear it apart. Not even graphene could withstand the forces. So the idea just isn't practical.

So if you create a hard shell, you have to ask: what is the intended goal?

If there is to create living area, where is gravity coming from? Do you spin the sphere? If so, it has the same centrifugal force problem.

If it's not (and technically even if it is) then you have the problem that the shell will collapse under the gravity of the star and/or its own mass.

Re: SETI@home shuts down after 21 years

#182

Post by otabdeveloper4 »

cletus wrote: post #80

Not to sound like a broken record (I and others have said this or similar on these kinds of threads) but... I, personally, have become convinced that looking for signals this way is actually pointless. The argument is basically this: 1. Within 1000 years (and maybe a lot less) we will have the engineering capability to build space habitats, powered by solar power. This last part is important because this thought expe…

Yes, but not for the reasons you outlined.

Use Occam's Razor: there are no aliens.

(Yes, I know I'm treading on some dearly-held religious beliefs now and will get lynched. Still, somebody had to say it.)

Re: SETI@home shuts down after 21 years

#184

Post by mdorazio »

otabdeveloper4 wrote: post #182
cletus wrote: post #80

Not to sound like a broken record (I and others have said this or similar on these kinds of threads) but... I, personally, have become convinced that looking for signals this way is actually pointless. The argument is basically this: 1. Within 1000 years (and maybe a lot less) we will have the engineering capability to build space habitats, powered by solar power. This last part is important because this thought expe…

Yes, but not for the reasons you outlined. Use Occam's Razor: there are no aliens. (Yes, I know I'm treading on some dearly-held religious beliefs now and will get lynched. Still, somebody had to say it.)

That's a bit too broad of a statement to be plausible. It's likely there are no aliens near us in time, space, technology, and desire to communicate to make such a search fruitful right now. There could very well be aliens on the other side of the galaxy that we can't see. There could have been aliens nearby a million years ago that are now extinct or elsewhere. There could be aliens right now that are pre-industrial or advanced enough to not communicate with methods that resolve on the bands SETI looks at. There could be aliens that follow a game theory mindset of non-communication ala The Dark Forest. Etc.

Space is ridiculously big. The universe is ridiculously old. Talking in absolutes about such things is a poor strategy.

Re: SETI@home shuts down after 21 years

#185

Post by hcs »

StillBored wrote: post #132
ars wrote: post #120

Earlier quoted context omitted.

Radar. That's the RF that's easiest to detect from long distances, it's focused, and it's strong. The hard part is deciding if it's natural or artificial.

That may not last much longer either. Transponders are more effective/useful for civilian purposes and the military needs to be stealthy. Big radar installations have a sign painted on them that says "take me out first".

What about radar for asteroid detection? https://en.wikipedia.org/wiki/Radar_astronomy

Re: SETI@home shuts down after 21 years

#187

Post by funnybeam »

jessaustin wrote: post #154
ravenstine wrote: post #8

In case anyone reads the headline and thinks that the SETI research center itself is shutting down, or that the project failed in some way: > "It's a lot of work for us to manage the distributed processing of data. We need to focus on completing the back-end analysis of the results we already have, and writing this up in a scientific journal paper," their news announcement stated. Maybe it's PR speak, but it does mak…

They've already completed construction of the ansible, the design of which was decoded several years ago.

Thank you for making me laugh at loud while making breakfast

Re: SETI@home shuts down after 21 years

#188

Post by killjoywashere »

We had a well-intended kid at a military facility in the early 2000s who loaded this on every computer he could log into. He genuinely thought he was doing a good thing for the world. Maybe he did. But the military network admins were none to pleased and he got somewhat more than a stern talking-to. Felt genuinely bad for him.

Re: SETI@home shuts down after 21 years

#189

Post by dusted »

milesward wrote: post #129
rootusrootus wrote: post #91

Earlier quoted context omitted.

Indeed they were. I had that exact setup. Overclocked the hell out of them. Unlike the 550 MHz someone else suggested, I'm 97.6% sure I only had them clocked at 450 MHz.

Yup, dual 450 celery was my gaaaangster setup at my silly startup :)

Dual celery story: Me being around 14, not allowed to build my own PC, but I got to spec it, I ordered dual CPU's. The company put in a dual slot 1 motherboard, and then two celerons in slot1 adapters.. that didn't support SMP. After complaining for a while, they traded the two celerons and adapters for a single P3 (I think I was being had). It took a year or two before I was able to afford the second P3. I still hold a grudge towards that particular computer shop, or I would, hadn't they gone out of biz. I did run a lot of SETI@home on that P3, it earned me my first two certificates :D

Re: SETI@home shuts down after 21 years

#190

Post by otabdeveloper4 »

mdorazio wrote: post #184
otabdeveloper4 wrote: post #182

Earlier quoted context omitted.

Yes, but not for the reasons you outlined. Use Occam's Razor: there are no aliens. (Yes, I know I'm treading on some dearly-held religious beliefs now and will get lynched. Still, somebody had to say it.)

That's a bit too broad of a statement to be plausible. It's likely there are no aliens near us in time, space, technology, and desire to communicate to make such a search fruitful right now. There could very well be aliens on the other side of the galaxy that we can't see. There could have been aliens nearby a million years ago that are now extinct or elsewhere. There could be aliens right now that are pre-industrial…

Okay, let me qualify: there are no aliens in the visible universe.

Of course what exists or doesn't exist in the universe that's not visible is pure unscientific speculation; might as well be made of blue cheese as far as science is concerned.

> Space is ridiculously big. The universe is ridiculously old.

This isn't true. Mathematical concepts of infinities and limits are "ridiculously big". Space is finite and thus ridiculously small.

Post reply on HN