Where are the Voyagers? | Hacker News Reader

Where are the Voyagers?

voyager.jpl.nasa.gov

204 pointslelf68 comments

> Because Earth moves around the sun faster than Voyager 1 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year.

So obvious yet so mind blowing.

We really are on a fragile blue ball doing loop-de-loops through space!

Wiggly loop-de-loops.

If you shrunk the sun down to the size of a ping-pong ball, earth would be a poppy seed orbiting ten meters away. Pluto would be 100m away. The Voyagers would be 300m away.

The nearest star, Proxima Centauri, would be 500 miles away.

Proxima Centauri is so far away that's depressing...

the proxima is almost a joke in the name.

Well, there are three stars in the alpha centauri system. Proxima is the most proximate

It is, but it's almost marginal:

https://en.wikipedia.org/wiki/Alpha_Centauri#/media/File:Rel...

> earth would be a poppy seed orbiting ten meters away

Correction: that should have been 10 feet (3 m). The other numbers are (more or less) correct.

Needs some metriculation /s

As amazing as space technologies are, we are in the stone ages when it comes to spaceflight:

> Earth moves around the sun faster than Voyager 2 is traveling from Earth, the distance between Earth and the spacecraft actually decreases at certain times of the year.

We don't even have the technology to escape the sun's gravity without needing a gravitational slingshot from other planets, and that still leaves us with a space craft moving slower than the earth.

Nitpicky but.... we'd still want to use gravitational slingshots even if we had more deltaVs to burn.

Yes, in fact per Mark Adler [0] you'd use a Jupiter flyby to fly back to the sun and then do a high thrust burn at closest approach to maximize your speed into interstellar space (Oberth effect).

[0] https://www.quora.com/Can-we-use-the-gravity-of-the-sun-to-s...

Problem is we don't really know where to go next. Jeff Bezos' Blue Origin tried to cook up alternate space travel methods for years and still couldn't come up with anything better than the same basic rocket model that put Gagarin into space.

Most theorized "warp drives" either require more energy than humanity is capable of producing or necessitate breaking a law of physics or two just to move anything organic or larger than a postage stamp.

Then again, the answer could be right under our noses. There's a Sci-fi story - I forget the name - where space travel is actually quite simple if you know the math to make it happen, and when a peaceful alien race visits Earth, the humans - with their thousands of years of armed conflict - kill the aliens and take their spaceships.

Makes me wonder that if we treat the rest of the universe the way we have treated our planet, do we truly deserve the right to roam the stars?

It would be nice, and is certainly the result I hope for (with all the good wishes do), as I'm not sure we will work very well with slow and expensive growth. Reading 'Against a Dark Background' was certainly interesting as it considers a system which essentially has its growth capped by the distance between itself and the rest of the universe.

Something I noticed in that novel is that they still had incredibly advanced technology. The Lazy Guns alone hint at what they lost!

Maybe there's a reason Golter is where it is, and maybe it wasn't always there.

I read _Against A Dark Background_ as a teen an thought of it as a pretty fun sf, almost space-opera adventure story. Then I read it again as an adult and... wow. Bank's SF work is very good, but the quiet existential horror that lurks behind the scenes in that novel really merits the title. Makes good old Lovecraft seem like a piker by comparison.

You write a good comment, I don't know why you were down voted.

I recall the story too: if I recall correctly, it was actually a branch of chemistry we had missed, not a math problem per se. The aliens stormed off the ships with muskets and we slaughtered 'em.

Not doing any kind of reconnaissance before a conflict would be crazy! But I guess maybe they didn't think of it!

It's also my working theory of why we won in Independence Day the movie :) Aliens were never warring among themselves and/or allowing any kind of a hacking culture, so didn't think to secure their systems!

I had come to the same conclusion with respect to ID which made the plot a lot easier to swallow.

They were essentially a hive mind working with a single purpose and were therefore incapable of conceiving the notion that they would need to secure their systems against an attack that essentially used their own technology against them.

There's the EM drive, maybe. Some recent discussion: https://news.ycombinator.com/item?id=12995125

If you can create trust out of electricty (ion drives also come to mind), then if you have nuclear power or fusion, things get interesting again in terms of propulsion.

To reach orbit, there are a bunch of interesting proposals: skyhooks (i.e. space elevator light), launch loops, railguns.

The EM drive is reported as producing maybe 1 mN per kW. The largest power plant in the world produces about 22 GW of energy--at that ratio, an EM drive could produce maybe 22 kN. The first stage of the Saturn V rockets produced 35,000 kN of thrust.

As a practical engine, EM drives are worse than chemical rockets or even ion thrusters (which produce about 25-250 mN/kW, according to Wikipedia).

Once we understand the physics, if it's a real phenomenon, we might be able to make it much more efficient. Compare a modern li-on battery to a lemon, coin and nail, for example.

This was a response to 'Problem is we don't really know where to go next'. Saying that there's basically nothing beyond chemical rockets.

My point is that there are plenty of possibilities to continue to develop propulsion technology.

If your numbers are correct, and I did the math correctly in my head, that's about five thousand pounds of thrust. A nuclear submarine might weigh ten thousand times that. Obviously a nuclear sub operates at much lower power level and obviously the hull doesn't have to be as thick for a spacecraft so I think it not a ridiculous comparison. Also you're spacecraft need not carry dozens of ICBMs, torpedoes, hundreds of sailors, etc.

Obviously the first engine ever exhaustively tested is usually not the highest performance achievable. A factor of a thousand seems possible although a hundred is more likely.

So for a very large nuclear plant, if the EM drive were weightless (LOL) then maybe 1/10th G applied to that nuclear sub is some kind of theoretical limit not entirely ridiculous but possible.

Now consider that to one sig fig a G of acceleration for a year is the speed of light. And if you're careful maybe you could run the plant for three decades.

So a round trip to the speed of light and back again is more or less back of the envelope possible to visit some distant star.

Relativity rears its ugly head and ten years of ship time around the speed of light is a lot further than 10 lightyears and time passing on earth is a lot longer than ten years.

Of course at the speed of light you're going to need a rather substantial hull, an active radar that can avoid interstellar crud, etc. If you can detect "stuff" at a day out, at a tenth of a G accelerating for an entire day you can be quite far away indeed by the time you pass it.

I can't run the numbers in my head like above, but even 1/100th G slices a very substantial amount of time off a Mars mission. Some unverified google results imply 1/100th G means Mars in a month not a year and a half.

At least as a back of the envelope calculation its quite a useful vehicle.

If you have a fusion power plant, you also have plenty of spent fuel to use as reaction mass.

> There's a Sci-fi story - I forget the name - where space travel is actually quite simple if you know the math to make it happen, and when a peaceful alien race visits Earth, the humans - with their thousands of years of armed conflict - kill the aliens and take their spaceships.

I think you might be thinking of Harry Turtledove's "The Road Not Taken". They weren't exactly friendly, but they were quite surprised by Man's ingenuity.

> we are in the stone ages when it comes to spaceflight

Indeed, only 59 years since we first put something into earth orbit.

We're just getting warmed up!

But that was only 54 years after figuring out powered flight.

It turns out that "getting off the ground" is also the hard part when it comes to space exploration.

"getting off the ground and staying there"

> We're just getting warmed up!

Literally, sadly.

Sigh..I see what you did there.

We could build something nuclear powered that would be able to do it. Project Orion or Project Daedelus would be able to escape the sun's gravity without needing a gravitational slingshot.

But we have decided for now not to build something like that.

Maybe in the next century at some point a nuclear powered spacecraft could be built in space that could start exploring other star systems.

>> nuclear powered spacecraft.

The voyagers are nuclear powered. They have RTGs powering their electronics and heat from those devices has changed their trajectories. The concept of a nuclear reactor powering an electric thruster isn't very far fetched. If we were going to go anywhere outside the solar system, that is the sort of nuclear power we would use.

Sein is probably referring to something running quite a bit hotter and likely exciting hydrogen atoms or other expendable fuel sources. I think these might have been looked at for purely interplanetary/solar travel in the past, but written off for the dangers of lifting cargo to orbit (think about the failure cases!) and also the general cost compared to alternatives.

If we had mining in lower gravity well areas (such as the asteroid belt) yielding that kind of fuel it might make a lot more sense.

Specifically, projects Orion and Daedalus are based on nuclear pulse propulsion[0], which is essentially detonating thermodynamic bombs behind the spacecraft. It's one of the only realistic options we currently have to do interstellar exploration. There was a discussion on HN not too long ago[1].

[0] https://en.wikipedia.org/wiki/Nuclear_pulse_propulsion

[1] https://news.ycombinator.com/item?id=12705705

Keep in mind that the Voyager probes weren't designed to go as fast as possible, they were designed to do planetary surveying while taking advantage of a rather favorable set of planetary alignments [1]. They could have been set on a much faster course if we were just concerned about getting them as far out into space as fast as possible. Voyager 1, for example, had its path altered away from Pluto to do a more in-depth survey of Titan.

Regardless, using planets to help speed things is just good sense. Think of going on a long trip in a car. You don't hook a trailer full of all the fuel you'll need to get to your destination, you stop at gas stations along the way. Using planets is a lot like that.

[1] https://en.wikipedia.org/wiki/Grand_Tour_program

New Horizons was launched directly into a solar escape trajectory.

It's going slower than Earth but that is no indication of how advanced the technology is. The whole goal was to get a close encounter with Pluto-Charon. What's the point in flying off into nothingness any faster after that?

Not really, earth is waaaay closer to the sun, so goes faster in its orbit but has a lot less energy (when normalised for mass) than any of the voyagers. They are going way faster than Earth in the sense that we're they to suddenly to telephone to Earth's perihelion, they'd be going ridiculously fast relative to Earth

It's sad to think they only have about 9 years of life remaining before they run out of power.

And only a couple of years of useful life remaining.

This is all very well, but where are they in the night sky is what I would like to know.

And no I'm not expecting to see them, just to think about them in the right direction.

This shows their positions on a sky chart: http://www.wolframalpha.com/input/?i=voyager+1,+voyager+2+sk...

I added: 'London, Tonight' on that query, and discovered they are only visible in the southern hemisphere. Boo.

Right Ascension: 17h 11m 31.0s Declination: 11° 57' 50.9" (J2000) http://theskylive.com/voyager1-tracker It's in the constellation Ophiucus.

It'll be doing a flyby of Gliese 445 in 40,000 years, but it'll be brick'd by then. http://www.space.com/22783-voyager-1-interstellar-space-star...

Geez, I wonder if anyone will find it.

And since we won't even survive this century due to climate change, it'll be "a relic of a civilization long gone."

We are totally gonna survive climate change! Humans are adaptable as fuck. We might lose 90% of life and our global economy might temporarily go away, but we'll survive.

Anyone know why in the second video (side plane view of solar system), they show 4 separate items moving out into deep space? I could pick Voyager 1 and 2, but no idea what the other 2 probes are?

Probably Pioneer 10 and 11.

See: https://en.wikipedia.org/wiki/List_of_artificial_objects_lea...

Pioneer 10 and 11 maybe?

Ah - thank you - Pioneer 10 and 11 makes sense!

You can ride along with Voyager in "Eyes on the Solar System" (https://eyes.nasa.gov) It's an open world Solar system with NASA missions and imagery.

I love NASA's work but I find it's websites are very messy and without a decent standard framework or layout. I really wish someone go to a GOV.UK job on them and get some decent standardisation going with them.

There are some standards for NASA websites, but I think they have more to do with responsibility for content and other bureaucratic matters than design concerns. The group I used to be with, the Scientific Visualization Studio, at svs.gsfc.nasa.gov has a pretty decent website, in my biased opinion.

I wrote a much less complete/polished program like this using WebGL this year:

https://wioux.github.io/tracking-station/

I was playing a lot of Kerbal Space Program and wanted to use those UI concepts to explore real missions and orbital maneuvers. I was particularly interested in the Cassini trajectory. But I started the project before discovering Eyes on the Solar System, which is awesome and now I find I'm kind of robbed of my motivation.

I wish my code runs without maintenance for so long as these "babies" fly.

I recently experienced a VxWorks system completely crashing due to a sequence of simple ftp (reading) commands. We had to go and manually restart the machine on-site.

Then I read about VxWorks being used for space exploration and was glad they never tried to read data from curiosity through ftp...

Would be really cool to stick some velocity numbers on there as well, I find it hard to relate to such huge distances. 62 thousand kilometres per hour feels larger because I can kind of comprehend it.

Though really cool anyway, I was going to say that Voyager 1 managed short of 30 light seconds a year until I realised the question is one of acceleration and deceleration not velocity. If I wasn't on my way to bed I would dig around for some data to make acceleration graphs for them (hint hint :P ).

> Would be really cool to stick some velocity numbers on there as well

Bottom of this page: http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm

That is a great resource, thank you

Leaving the solar system, as usual.[1]

[1] https://xkcd.com/1189/

Eventually, the Voyagers will pass other stars. In about 40,000 years....

I love that you can almost reasonably measure their distance in lightyears.

Um, what about Voyager 6? I'm worried...

You mean V'ger?

It's programmed to learn all that is learnable, then return to the creator. I wouldn't worry.

> I wouldn't worry

Yeah... what could go wrong, eh?

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