Voyager 1 spots new region at the edge of the Solar System(arstechnica.com)
arstechnica.com
Voyager 1 spots new region at the edge of the Solar System
http://arstechnica.com/science/2012/12/voyager-1-spots-new-region-at-the-edge-of-the-solar-system/
68 comments
Strictly speaking, the RTGs will continue generating power past that time -- it just won't be enough to power any of the instruments or the radio; the thermocouples also degrade, which further impacts the power produced. (tomato, tomahto) Attitude propellant is also an issue. Around 2020, they'll start to turn off instruments until they don't have enough power to run any of them anymore. Apparently, they haven't picked the shutdown order yet -- but they have 10 years to decide, so no rush. =)
NASA's timeline for the Voyager lifetimes: http://voyager.jpl.nasa.gov/spacecraft/spacecraftlife.html
NASA's timeline for the Voyager lifetimes: http://voyager.jpl.nasa.gov/spacecraft/spacecraftlife.html
It would be cool if they could shut it down for a long time then have it wake up and send some data back with the remaining power.
Neat idea, but I don't think there were any onboard batteries -- AFAIK power was just fed straight from the RTG thermocouples, more or less. Batteries would have just added weight, would have had a crappy recharge capacity after a while, and wouldn't have made much sense for a deep space probe which relied on an RTG instead of solar panels.
Also, the RTG might be powering instrument heaters, keeping them at warm enough temperatures to prevent failure. If that's the case, once those are shut off, there's no turning those instruments back on.
EDIT: It appears that Voyager 1's ultraviolet spectrometer instrument, at least, is pretty tough: as of January 2012, it has survived having its heater shut off for power conservation: http://www.nasa.gov/mission_pages/voyager/voyager20120117.ht...
That's one hardy spacecraft! =)
Also, the RTG might be powering instrument heaters, keeping them at warm enough temperatures to prevent failure. If that's the case, once those are shut off, there's no turning those instruments back on.
EDIT: It appears that Voyager 1's ultraviolet spectrometer instrument, at least, is pretty tough: as of January 2012, it has survived having its heater shut off for power conservation: http://www.nasa.gov/mission_pages/voyager/voyager20120117.ht...
That's one hardy spacecraft! =)
Should have went with the extended extended-battery.
Ha, true. From what I can find, each of Voyager 1's RTGs is about 5% of the total mass of Voyager 1, so about 15% of it's mass total. Seems surprisingly low to me, considering they are basically trashcans full of plutonium. I'm not sure how many more you would have to add to keep Voyager 1 operating longer, but the more you add the slower it would ultimately be going (well, the harder it is to get it going the speed the mission required). My guess is that additional/larger RTGs couldn't be justified or technically pulled off at the time.
I wonder what the expected lifetime of the crafts were when they were designed back in the 70s. Maybe they thought the RTGs would outlive the other components?
My thoughts exactly -- they probably didn't bother putting a whopping big 100-year RTG on there because they didn't figure the electronics would last long enough, or they figured they'd run out of attitude propellant long before then.
You could look up the planned mission duration, but all this would tell you would be the duration that they were absolutely designed to work for -- kind of like how the Mars rover missions were 90 sols, but in actuality they've gone over 2,000 (albeit with solar panel dust issues, busted wheel motors, etc).
You could look up the planned mission duration, but all this would tell you would be the duration that they were absolutely designed to work for -- kind of like how the Mars rover missions were 90 sols, but in actuality they've gone over 2,000 (albeit with solar panel dust issues, busted wheel motors, etc).
Well I mean, Voyager 1, launched in 1977, has been on the "interstellar mission" since 1980 (32 years) and is planned to go into the 2020's (total of more than 40 years). That doesn't quite work out to the (2000-90)/90 ratio (though the distance traveled by Opportunity is an even more impressive ratio), but I think it is pretty damned impressive nevertheless. It was definitely engineered to last a lot longer than the Jupiter/Saturn observation mission required; I feel like both came from the same "school" of engineering and mission planning.
This sort of thing is a natural consequence of high cost and high risk missions. You have a multi-billion dollar mission, and it's doing something unprecedented and using a brand new design and construction. When you build something like that what tends to happen is that you try to keep the mission scope reasonable and then you build the vehicle to have a very high (say >95%) chance of satisfying that minimum mission requirement. But what happens when, say, you create a Mars rover with a 95% chance of working for 90 days you'll likely end up engineering a vehicle which might have, say, a 50% chance of lasting for 5 years. If you set out to do that from the start it would be a non-starter, because a 50% mission success rate is too low for a multi-billion dollar mission.
I'm guessing they figured there'd be other much more advanced and capable space probes overtaking the Voyagers well before the power got this low…
Not at all, actually. The whole interstellar mission aspect of the mission was entirely a beneficial side effect. In fact, the only part of the mission that was planned from the start was the Jupiter and Saturn encounters. The mission ended up becoming an outer Solar System "grand tour" due to a fortuitous planetary alignment, but only Voyager 2 was able to visit Uranus and Neptune. The interstellar mission was entirely unplanned and was funded mostly because it has been relatively inexpensive and for various reasons the Voyager craft have suitable instruments for studying the magnetic, particle, and dust environment in the outer Solar System and interstellar space.
Oh man I get so excited every time I hear news from the Voyager program.
What an amazing achievement to do what those guys did back in the 1970s.
What an amazing achievement to do what those guys did back in the 1970s.
Yes, same here. It's an inspiring craft for me. I was enchanted by the program as a kid. Distant voyage, golden records, Carl Sagan... almost a romantic sci-fi novel :) I was a bit sad to know that it'll never be seen again. But now I think it's likely that one day we'll find it and put in a museum. Possibly on Mars :)
No kidding. When I saw the headline, my heartrate spiked a noticeable amount while I waited for the link to load.
Don't diss the 70s. The 50s went to space. The 60s went to the moon. The 70s left the solar system. Progress...
The 70s went to space. The 80s shifted right.
The 1970s essentially carried on from the 1950s and 1960s. The Vietnam war, resource shocks, etc. seem to have killed any real innovation during the 70s (in government/aerospace -- obviously it was better in other fields like microcomputers), and then the shift toward military in the 80s went even farther.
(there was a shift right overall, but it was mostly just a shift down in space funding, I think)
(there was a shift right overall, but it was mostly just a shift down in space funding, I think)
I was trying to visualize the so called 'magnetic highway' and found this along with further explanation.
http://phys.org/news/2012-12-voyager-encounters-region-deep-...
http://phys.org/news/2012-12-voyager-encounters-region-deep-...
> A few models did have a feature like this, but it was only a transient one that appeared at certain times of the solar cycle.
How transient is transient? 30 days is not a large fraction of an 11 year solar cycle.
How transient is transient? 30 days is not a large fraction of an 11 year solar cycle.
I'm wondering about that, too. Shouldn't the article say something like, "The new data lend support to models predicting that a region with the observed properties will appear during certain parts of the solar cycle." Is that statement not true?
Perhaps they didn't predict it at this particular point of the solar cycle?
So instead of a hard delineation between solar wind and cosmic rays we're seeing something more like velcro?
How fast is Voyager travelling? Could we send out a Voyage X at a faster speed and with better tech to catch up and surpass it?
If you wanted to have a probe pass Voyager 1 in 10 years, you would need to launch it today and get it going 15.9 AU/year, which is blazing fast. Almost 5 times as fast as Voyager 1. New Horizon, if launched today, could almost do it (14.13 AU/year), but it's mission wasn't set up to leave it traveling as fast as Voyager 1. Although it's going out in the same direction and was launched faster, it will ultimately end up going slower.
If you give yourself 10 years to design the probe and something to get it going that fast, then the speed you actually need jumps up to 19.5 AU/year. The longer it takes you to design your fast rocket, the faster it has to go in order to catch Voyager 1 in the same amount of time.
Realistically, unless something exotic happens in space propulsion technology, we will never catch Voyager 1 within our lifetime. If we launched today at twice the speed of Voyager 1, then we could catch it in around 50 years, but that's not going to happen.
If you give yourself 10 years to design the probe and something to get it going that fast, then the speed you actually need jumps up to 19.5 AU/year. The longer it takes you to design your fast rocket, the faster it has to go in order to catch Voyager 1 in the same amount of time.
Realistically, unless something exotic happens in space propulsion technology, we will never catch Voyager 1 within our lifetime. If we launched today at twice the speed of Voyager 1, then we could catch it in around 50 years, but that's not going to happen.
Catch up and surpass something we launched decades ago, travelling (according to Wikipedia, entry was last edited .. today) 3.595 AU per year [1].
The question you're asking is hard to answer: When do you want to catch up? If we send a new object to space today, which travels 5% faster, is that good enough? It won't pass Voyager 1 for a looooong time, but will eventually.
Is that what you're aiming for? Why? Or are you asking for a magical way to cross that distance (35 years of traveling) 'instantly'?
1: http://www.wolframalpha.com/input/?i=3.595+AU+per+year&d...
The question you're asking is hard to answer: When do you want to catch up? If we send a new object to space today, which travels 5% faster, is that good enough? It won't pass Voyager 1 for a looooong time, but will eventually.
Is that what you're aiming for? Why? Or are you asking for a magical way to cross that distance (35 years of traveling) 'instantly'?
1: http://www.wolframalpha.com/input/?i=3.595+AU+per+year&d...
Considering c is 63,198 AU/yr, and Voyager 1's only about 123 AU away, there's still a lot of room left for future engineers in increasing the speed of our devices to very quickly surpass it. Will we achieve even a hundredth of c within the next 100 years? Depends.
Just wondering, is there any technology we've seen actually used today that could produce a hundredth of c within the next 100 years? Would this be something we could see with ion propulsion for example?
Not used, but planned. Nuclear propulsion. No real limit on speed, apart from C, although as you go farther/faster you need REALLY big ships to carry enough fuel. c.f. project Orion.
Voyager did pass Pioneer 10 (1972) in the late 1990s. The alignment mentioned by others made the difference. New Horizons, which is going to Pluto, had the fastest launch speed of any man made object.
Launch speed isn't the whole story though. You can accelerate to ludicrous speeds once you're in space. Compare the following to New Horizon's launch speed of 16 km/s:
http://en.wikipedia.org/wiki/Helios_probes (70 km/s)
http://en.wikipedia.org/wiki/Solar_Probe%2B (theoretical 200 km/s)
http://en.wikipedia.org/wiki/Helios_probes (70 km/s)
http://en.wikipedia.org/wiki/Solar_Probe%2B (theoretical 200 km/s)
Note that those are going towards the sun, not away from it, and so benefitting from the sun's gravity instead of having to fight it.
Accelerating to ludicrous speed on the way out of the solar system is much more difficult.
My understanding (though I'm no astrophysicist) is that gravity boost from a planet works because of the relative velocities between the planet and the sun, whereas trying to use the sun's gravity to boost your solar system escape velocity would fail since gravity would be fighting you on the way out just as much as it was helping you on the way in.
Accelerating to ludicrous speed on the way out of the solar system is much more difficult.
My understanding (though I'm no astrophysicist) is that gravity boost from a planet works because of the relative velocities between the planet and the sun, whereas trying to use the sun's gravity to boost your solar system escape velocity would fail since gravity would be fighting you on the way out just as much as it was helping you on the way in.
This is correct. Planetary gravitational slingshots work with respect to Sun-relative velocities. Trying to use the Sun to slingshot out of the solar system is like trying to use Earth's gravity to sling into Earth orbit. Being at the bottom of a gravity well cannot help you to leave it. It's like riding a bike down a hill; you can't then use the kinetic energy to roll up a bigger hill than you started from.
A gravity assist works by robbing orbital momentum from the planet, transferring it to the spacecraft. (I once saw a calculation that Voyager's slingshot slowed Jupiter's motion by one foot per trillion years.) Jupiter has orbital momentum around the Sun, but the Sun has no orbital momentum around itself.
Flying past the Sun could give you velocity relative to the galactic center, making use of the Sun's orbit around that. But that velocity doesn't help you leave the Sun's neighborhood or travel within the Solar System, because the gained velocity is in the same direction as the Sun and Solar System are already moving.
A gravity assist works by robbing orbital momentum from the planet, transferring it to the spacecraft. (I once saw a calculation that Voyager's slingshot slowed Jupiter's motion by one foot per trillion years.) Jupiter has orbital momentum around the Sun, but the Sun has no orbital momentum around itself.
Flying past the Sun could give you velocity relative to the galactic center, making use of the Sun's orbit around that. But that velocity doesn't help you leave the Sun's neighborhood or travel within the Solar System, because the gained velocity is in the same direction as the Sun and Solar System are already moving.
My understanding (though I'm no astrophysicist) is that gravity boost from a planet works because of the relative velocities between the planet and the sun, whereas trying to use the sun's gravity to boost your solar system escape velocity would fail since gravity would be fighting you on the way out just as much as it was helping you on the way in.
Yes, this is basically correct. What a gravity boost from a planet does is transfer a very small amount of the planet's orbital kinetic energy to the spacecraft; it puts the planet into a slightly smaller orbit, and boosts the spacecraft to a higher speed on its way out. Since the Sun is what the planets are orbiting, this trick obviously won't work the same way with the Sun.
(Technically, the Sun itself, or more precisely the center of mass of the Solar System, is orbiting the center of the galaxy; so I suppose it would be theoretically possible to fly a spacecraft by the Sun in such a way as to transfer a very small amount of its orbital kinetic energy with respect to the center of the galaxy to the spacecraft, so it would fly outward faster than it went in, even after taking into account the slowdown climbing out of the Sun's gravity well. But I doubt we're going to be in any practical position to try this any time soon.)
Yes, this is basically correct. What a gravity boost from a planet does is transfer a very small amount of the planet's orbital kinetic energy to the spacecraft; it puts the planet into a slightly smaller orbit, and boosts the spacecraft to a higher speed on its way out. Since the Sun is what the planets are orbiting, this trick obviously won't work the same way with the Sun.
(Technically, the Sun itself, or more precisely the center of mass of the Solar System, is orbiting the center of the galaxy; so I suppose it would be theoretically possible to fly a spacecraft by the Sun in such a way as to transfer a very small amount of its orbital kinetic energy with respect to the center of the galaxy to the spacecraft, so it would fly outward faster than it went in, even after taking into account the slowdown climbing out of the Sun's gravity well. But I doubt we're going to be in any practical position to try this any time soon.)
For those who don't know what a gravity boost is, here is the simple picture.
In the reference frame of the planet you will travel in a hyperbola as you go by. The incoming branch is from the front of the planet, the outgoing branch is also in the front of the planet. So you go from moving backwards to moving forwards.
However the planet is moving in the reference frame of the Sun. The initial "moving backwards" is actually more like "sitting there". The ending "moving forwards" is actually something like, "moving up to 2x as fast as the planet".
So a gravity boost only looks like a gravity boost in a reference frame that is moving relative to the object. Furthermore the gravity boost also does nothing to help you to escape from the object you're getting the gravity boost from.
Therefore we cannot get a gravity boost from the Sun to leave the Solar System. And a gravity boost from the Sun does not look like a gravity boost to us, in orbit around the Sun.
In the reference frame of the planet you will travel in a hyperbola as you go by. The incoming branch is from the front of the planet, the outgoing branch is also in the front of the planet. So you go from moving backwards to moving forwards.
However the planet is moving in the reference frame of the Sun. The initial "moving backwards" is actually more like "sitting there". The ending "moving forwards" is actually something like, "moving up to 2x as fast as the planet".
So a gravity boost only looks like a gravity boost in a reference frame that is moving relative to the object. Furthermore the gravity boost also does nothing to help you to escape from the object you're getting the gravity boost from.
Therefore we cannot get a gravity boost from the Sun to leave the Solar System. And a gravity boost from the Sun does not look like a gravity boost to us, in orbit around the Sun.
You can go look it up, but IIRC, the slingshot method (using a rare alignment of planets) produced a higher "speed" (so to speak) than would be reasonable to produce even with today's technology. (i.e taking the same budget today and doing everything we can to get a probe out at the same "speed" would be impossible).
I'm not sure if it's actually impossible. IANA physicist, but if your singular all-consuming goal was to get out of the solar system as fast as possible you could probably get a better gravity assist from a single pass of the sun than Voyager got from the entire grand tour.
(Feel free to correct me, physicists!)
The bigger issue is convincing someone to hand you millions of dollars to literally throw away faster than anything in prior human history.
(Feel free to correct me, physicists!)
The bigger issue is convincing someone to hand you millions of dollars to literally throw away faster than anything in prior human history.
Well, technically most of the mission cost would be spend on Earth (paying Earth engineer salaries, and Earth factory bills), so the money never leaves Earth. The only money you are literally throwing is the material cost of the rocket and probe, which would be fairly low (the cost of a bunch of titanium (or whatever the rocket/probe is made of), silicon not worth measuring, the rocket fuel (which is surprisingly cheap), etc.
> get a better gravity assist from a single pass of the sun
No. The gravity assist is because of the motion of the planets around the sun. The sun isn't moving relative to itself. There are some other things you can do where the sun can help, but not a slingshot.
No. The gravity assist is because of the motion of the planets around the sun. The sun isn't moving relative to itself. There are some other things you can do where the sun can help, but not a slingshot.
From: http://en.wikipedia.org/wiki/New_Horizons
Provided it survives that far out, New Horizons is likely to follow the Voyager probes in exploring the outer heliosphere and mapping the heliosheath and heliopause. Even though it was launched far faster than any outward probe before it, New Horizons will never overtake Voyager 1 as the most distant man-made object from Earth. Close fly-bys of Saturn and Titan gave Voyager 1 an advantage with its extra gravity assist. When New Horizons reaches the distance of 100 AU, it will be travelling at about 13 km/s (29,000 mph), around 4 km/s (8,900 mph) slower than Voyager 1 at that distance.
Provided it survives that far out, New Horizons is likely to follow the Voyager probes in exploring the outer heliosphere and mapping the heliosheath and heliopause. Even though it was launched far faster than any outward probe before it, New Horizons will never overtake Voyager 1 as the most distant man-made object from Earth. Close fly-bys of Saturn and Titan gave Voyager 1 an advantage with its extra gravity assist. When New Horizons reaches the distance of 100 AU, it will be travelling at about 13 km/s (29,000 mph), around 4 km/s (8,900 mph) slower than Voyager 1 at that distance.
We could but it wouldn't be easy. Likely what we'd do is use a really big rocket like the Delta IV Heavy or the upcoming Falcon Heavy to give the spacecraft a lot of extra speed. Then we'd use electric propulsion on the craft itself to continue to build up speed over its life. Ultimately, even with today's technology, we could catch up to these probes but it would take decades to do so.
Sure, but even at x2 speed it will take decades.
I wonder how hard it would be to do purely private (or maybe university-consortium) deep space probes. I assume almost any of the standard rockets could accommodate an extra stage to do escape, especially if you just need earth escape and can steal mv from other bodies to escape the solar system.
The expensive part would be operating it indefinitely, right? I assume you could outsource to a satellite TT&C facility.
The expensive part would be operating it indefinitely, right? I assume you could outsource to a satellite TT&C facility.
What I find most interesting about Voyager-1 and 2, that these crafts went to the outskirts of our Solar system because of funding cuts for Mariner program (Venus and Mars research). Marvelous what you can achieve even when you are given less money.
I have mixed feeling every time I read this kind of news. I envy those people who made it happen 35 years ago, they produced stuff that's still sophisticated by today's standard, while I'm here writing crappy websites. Man, I feel small.
Could it be instruments degrading? 35 years in the cosmic wind is a long time.
I had to double check when I read that the Voyagers started their mission 35 years ago, it's hard to believe.
Why aren't we sending more of these, in every direction?
Why aren't we sending more of these, in every direction?
Well the ESA is going to send one, but the answer is simply budget. It takes money to run one of these missions, it competes with other missions. Not only is there the space craft cost, the launch cost, and the team cost, since its going to take a long time to get out there you've got to have 50 years of time reserved on the deep space network etc etc.
A good question would be "Why are the space sciences so under funded?" and that policy question is best addressed with your legislators. Lately I've been positioning space as a 'back up plan' [1] for the Global Warming crisis.
[1] Motivating politicians is hard, especially if they can't point at what they've done and say "See how impressive is that!" Space sounds like a 'waste' to a lot of voters, so I've been taking the tack, "Global Warming is a crisis, and we don't yet know how to control the climate on our planet, we may get to a point where we are seriously thinking about moving off planet and this information will be invaluable, there is also the asteroid threat which space craft "out there" where the most likely earth killing asteroids are hiding (the Ooort cloud) would be a tremendous early warning, you might be saving the entire human RACE by funding these projects at NASA, how cool is that?!"
A good question would be "Why are the space sciences so under funded?" and that policy question is best addressed with your legislators. Lately I've been positioning space as a 'back up plan' [1] for the Global Warming crisis.
[1] Motivating politicians is hard, especially if they can't point at what they've done and say "See how impressive is that!" Space sounds like a 'waste' to a lot of voters, so I've been taking the tack, "Global Warming is a crisis, and we don't yet know how to control the climate on our planet, we may get to a point where we are seriously thinking about moving off planet and this information will be invaluable, there is also the asteroid threat which space craft "out there" where the most likely earth killing asteroids are hiding (the Ooort cloud) would be a tremendous early warning, you might be saving the entire human RACE by funding these projects at NASA, how cool is that?!"
It's not just budget ,the Voyager program took advantage of a favorable planetary alignment that wouldn't recur for 175 years: http://en.wikipedia.org/wiki/Planetary_Grand_Tour
I have no idea how favorable this was, i.e. whether you could get the same effect today with more propulsion, but it's quite possible that we don't have the technology to do this in any reasonable timeframe today.
I have no idea how favorable this was, i.e. whether you could get the same effect today with more propulsion, but it's quite possible that we don't have the technology to do this in any reasonable timeframe today.
That alignment was more about favourable planetary alignment than a noticeably faster trip to the edge of the solar system.
The Voyagers did pretty well, but if your only aim was getting away from Sol it's not too difficult a target. See also: http://en.wikipedia.org/wiki/Interplanetary_Transport_Networ....
The Voyagers did pretty well, but if your only aim was getting away from Sol it's not too difficult a target. See also: http://en.wikipedia.org/wiki/Interplanetary_Transport_Networ....
"New Horizons was launched on January 19, 2006" ... "with an estimated arrival date at the Pluto–Charon system of July 14, 2015"
Holy shit! Only 9 years to pluto? That's waaaaayyyy shorter than I would have imagined possible with our current technology.
You say that like it's a long time! I think.
What can happen to our planet that would make it less hospitable than Mars or deep space? Most of the threats (global warming, asteroid strike, etc) still leave Earth with a usable atmospheric pressure and breathable oxygen, they just affect food supply (there is no food on Mars), or other things that still leave you better off than facing the vacuum of space.
I remember reading a story when I was a kid, about a future society that moved underground to get away from unfavorable planet conditions. The description was remarkably like what I'd picture as a large scale off-planet settlement -- everyone living in a rather confined space, and kids only knowing about what Earth was like from reading books and watching old movies.
I remember reading a story when I was a kid, about a future society that moved underground to get away from unfavorable planet conditions. The description was remarkably like what I'd picture as a large scale off-planet settlement -- everyone living in a rather confined space, and kids only knowing about what Earth was like from reading books and watching old movies.
If you believe the James Lovelock and the Gaia hypothesis, the environment is stabilised by multiple negative feedback loops. However, the feedback is limited and will only compensate for a certain range of inputs - if these are exceeded, the entire system could "flip" into another stable configuration. Lovelock suggests that this has already happened once on Earth; the change from an anaerobic atmosphere to the present oxygen/nitrogen atmosphere, caused by the "pollution" excreted by anaerobic lifeforms (the bacteria now mostly relegated to your intestines).
It's an interesting hypothesis with a fair bit of research ("daisyworld" simulation of global temperature stabilisation via albedo effects, the methyl iodide cycle, etc.)
I believe his current position is that we're all doomed and the "flip" is underway.
It's an interesting hypothesis with a fair bit of research ("daisyworld" simulation of global temperature stabilisation via albedo effects, the methyl iodide cycle, etc.)
I believe his current position is that we're all doomed and the "flip" is underway.
Well the fossil record shows that asteroid strikes and gross changes in climate are strongly correlated with mass extinction events.
Sadly enough most people and their legislators find it hard to devote money to something that is extremely long term (Decades or even centuries). I think the best we can hope for for more funding in Space is competition from China in the form of a space arms-race.
I would like to know the name of the politician that thinks that many elections ahead.
In this case its "how history will remember them." Having talked with a number of congress people over the years in various stages (campaigning, lame duck, between elections, Etc) there is certainly a desire not to be known for a scandal or indiscretion.
Thanks for the serious response - politics brings out the cynic in me.
In this case it makes more sense to privatize these sort of things.
We've shifted to orbiters instead of one-shot flybys. Galileo at Jupiter, Cassini at Saturn, Messenger at Mercury, Juno on the way to Jupiter now. A ten year spacecraft mission can deliver a lot more science when it's orbiting a planet (or driving around on it) rather than cruising through endless void.
(New Horizons is set to flyby Pluto, because orbiting it wasn't feasible as the dwarf planet doesn't have nearly enough mass to capture a fast incoming spacecraft. New Horizons would have had to fly to Pluto much slower if it wanted to orbit it.)
(New Horizons is set to flyby Pluto, because orbiting it wasn't feasible as the dwarf planet doesn't have nearly enough mass to capture a fast incoming spacecraft. New Horizons would have had to fly to Pluto much slower if it wanted to orbit it.)
The magnetic highway begs to differ. There is value in both kinds of missions.
Cynical-me thinks "economic rationalism and the decline of cold war dick-size-competition".
I hope I'm wrong…
I hope I'm wrong…
> Today's announcement clarifies that the confusion was caused by the fact that nature didn't think much of physicists' expectations.
LOL
LOL
Maybe it's V Ger! Look out Capt Kirk!!!
The RTGs in Voyager 1 are only good until about 2025 iirc, ~12-13 more years. Here's hoping it makes it through in time.