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

Voyager 2’s Discoveries from Interstellar Space

nytimes.com

Post reply on HN
Print view View original

31–40 of 109 posts

Re: Voyager 2’s Discoveries from Interstellar Space

#31

Post by kromem »

flurdy wrote: post #12

I am always baffled by the conundrum of the futility of launching a spacecraft to go far away by our own ability to invent faster engines. Say it takes 300 years to get to Alpha Centauri. If you launch it you have 150 years to invent a spacecraft that goes twice the speed of the first one. Very likely. If you launch that one it will overtake the other one. Now you have 75 years to find an even faster engine. Launch i…

The irony is that without the practical experience of those intermediate steps, you might never reach the point where the diminishing returns become negligible.

You're basically describing the reverse of Zeno's paradox - the "why bother" paradox.

Re: Voyager 2’s Discoveries from Interstellar Space

#32

Post by vardump »

pm90 wrote: post #13
flurdy wrote: post #12

I am always baffled by the conundrum of the futility of launching a spacecraft to go far away by our own ability to invent faster engines. Say it takes 300 years to get to Alpha Centauri. If you launch it you have 150 years to invent a spacecraft that goes twice the speed of the first one. Very likely. If you launch that one it will overtake the other one. Now you have 75 years to find an even faster engine. Launch i…

"Why should I buy a computer today, when a computer in 10 years can do a ton more for less money?"

Say you built a computer in late 2009 with AMD Radeon HD 5870, Intel Core i7 975, Intel's X25-M SSD and 16 GB RAM.

That computer would still feel pretty snappy today for desktop tasks, running dual 2560x1440 screens. Although new AAA games would probably have issues, either low frame rates or not running at all. Most indie games would work just fine.

I think the change will be even less in next 10 years. 2019 hardware will perform just fine in 2029.

Unless something dramatically different pops up, we're in the era of diminishing returns.

Re: Voyager 2’s Discoveries from Interstellar Space

#33

Post by Sendotsh »

ngcc_hk wrote: post #16
daveslash wrote: post #11

Not a comment of the article itself, but for anyone interested in both Voyagers, PBS recently did a great documentary called "The Farthest" . I highly recommend it. http://www.pbs.org/the-farthest/home/

Thanks but only for American

The link just goes to a trailer for the movie which is available on DVD/iTunes/etc.

You can see the same trailer on YouTube: https://www.youtube.com/watch?v=VwT3QgKORuQ

Re: Voyager 2’s Discoveries from Interstellar Space

#34

Post by mrbonner »

mlthoughts2018 wrote: post #27
ChuckNorris89 wrote: post #2

I'm amazed and still can't get my head around how today we can receive images and valuable data from a device which is currently lightdays away from us and was built with 60's technology & know-how and is operating well beyond it's expected lifetime. I raise my glass to the engineers who worked on this. Makes my daily programming tasks feel stupid in comparison. Edit: corrected, thanks for the numbers

Yeah but did they use Agile methods and have good team velocity as they burned down the backlog? If not, how can we really be sure the project was a success?

I like your comment but it got down voted into oblivion probably because you forgot the /s tag. Some folks are serious here.

Re: Voyager 2’s Discoveries from Interstellar Space

#35

Post by anthony_doan »

flurdy wrote: post #12

I am always baffled by the conundrum of the futility of launching a spacecraft to go far away by our own ability to invent faster engines. Say it takes 300 years to get to Alpha Centauri. If you launch it you have 150 years to invent a spacecraft that goes twice the speed of the first one. Very likely. If you launch that one it will overtake the other one. Now you have 75 years to find an even faster engine. Launch i…

You can't get faster engine without having slower one first.

How do they even know what to improve upon without building it and experiment with it?

Also simulation is not a replacement for real world testing. They should launch stuff into space to figure out if it works and their simulation is making the correct assumptions.

Also I'd imagine these launches are sending back valuable data that they can use to make adjustment and improvement for future engines.

Re: Voyager 2’s Discoveries from Interstellar Space

#36

Post by wyldfire »

petschge wrote: post #8
ChuckNorris89 wrote: post #2

I'm amazed and still can't get my head around how today we can receive images and valuable data from a device which is currently lightdays away from us and was built with 60's technology & know-how and is operating well beyond it's expected lifetime. I raise my glass to the engineers who worked on this. Makes my daily programming tasks feel stupid in comparison. Edit: corrected, thanks for the numbers

Voyager 1 is 0.00234 light years from Earth, Voyager 2 is 0.00194 ly. Or in more useful units: 20.5 and 17 light hours. Also we do not receive images any more (the cameras were made for planetary encounters and have been turned off long ago). But yes, getting data (at 160 bits per second) from man made objects that are the better part of a light day away is impressive. Even more so because they have been working for…

Are they powered via PV? IIRC one of them (satellite/probes) had some nuclear fuel.

Re: Voyager 2’s Discoveries from Interstellar Space

#37

Post by stan_rogers »

vardump wrote: post #32
pm90 wrote: post #13

Earlier quoted context omitted.

"Why should I buy a computer today, when a computer in 10 years can do a ton more for less money?"

Say you built a computer in late 2009 with AMD Radeon HD 5870, Intel Core i7 975, Intel's X25-M SSD and 16 GB RAM. That computer would still feel pretty snappy today for desktop tasks, running dual 2560x1440 screens. Although new AAA games would probably have issues, either low frame rates or not running at all. Most indie games would work just fine. I think the change will be even less in next 10 years. 2019 hardwar…

That's more or less the result of having already waited. There was a time, not very long ago in the grand scheme of things, when the computer you wanted would cost $5000 and be essentially obsoleted by the $5000 computer coming in 60-90 days. (Perspective: PC review magazines of the day would usually include the time for a Gaussian blur on a 1MP image as a meaningful test.) When you were talking about cutting minutes off of a large spreadsheet recalc, the immediate gain from upgrading today had to be measured carefully against the even greater gains possible next quarter.

Re: Voyager 2’s Discoveries from Interstellar Space

#38

Post by dekhn »

ChuckNorris89 wrote: post #2

I'm amazed and still can't get my head around how today we can receive images and valuable data from a device which is currently lightdays away from us and was built with 60's technology & know-how and is operating well beyond it's expected lifetime. I raise my glass to the engineers who worked on this. Makes my daily programming tasks feel stupid in comparison. Edit: corrected, thanks for the numbers

I know a person who worked on voyager. He is a very smart person who has contributed to a wide range of technologies over a long period of time. I have talked to him and the reality is that by the time that project was being done, the people who ran it had a lot of experience, and they applied the hell out of it to the project.

I've spent a lot of time since then looking into how to build reliable systems that operate for decades and... there are no easy answers. You have to have an amazing amount of knowledge about the engineering context (what's it like to run a computer in space), the scientific mission (IE, given this payload mass, what instruments can we fit), judicious software engineering skills (just updating the firmware on a machine that's millions of miles away is a challenging problem, worse yet if updating the firmware bricks your control plane), project management skills (to ensure you make your launch date), and the dedication to keep things going long after most people got bored of them.

After a long time playing with complicated systems I went back and played with 8-bit microcontrollers and they were actually really fun because it forces you to build systems that are reliable without a terminal and resource constrained (you'd have a hard time fitting a program as large as this comment into an arduino...)

Re: Voyager 2’s Discoveries from Interstellar Space

#39

Post by klyrs »

Ancalagon wrote: post #3
ChuckNorris89 wrote: post #2

I'm amazed and still can't get my head around how today we can receive images and valuable data from a device which is currently lightdays away from us and was built with 60's technology & know-how and is operating well beyond it's expected lifetime. I raise my glass to the engineers who worked on this. Makes my daily programming tasks feel stupid in comparison. Edit: corrected, thanks for the numbers

Just FYI nothing man made is even close to light years away from the Earth. EDIT: I don't understand the downvotes. Isn't this just fact? EDIT 2: I see the OP changed his original comment, so I can understand the confusion. Thanks all :)

> EDIT: I don't understand the downvotes. Isn't this just fact?

Nobody's questioning that fact (barring well-deserved pedantry about radio signals), but GP's claim was light days so the downvotes are probably about the nonsequitur.

Re: Voyager 2’s Discoveries from Interstellar Space

#40

Post by FredFS456 »

wyldfire wrote: post #36
petschge wrote: post #8

Earlier quoted context omitted.

Voyager 1 is 0.00234 light years from Earth, Voyager 2 is 0.00194 ly. Or in more useful units: 20.5 and 17 light hours. Also we do not receive images any more (the cameras were made for planetary encounters and have been turned off long ago). But yes, getting data (at 160 bits per second) from man made objects that are the better part of a light day away is impressive. Even more so because they have been working for…

Are they powered via PV? IIRC one of them (satellite/probes) had some nuclear fuel.

They're powered by Radioisotope Thermoelectric Generators. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...
Post reply on HN