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Voyager 1 Finds Unexpected Wrinkles At the Edge Of the Solar System
Voyager 1 has been close to the boundary of the solar system for quite a while; we've mentioned that the edge is near a few times before, including an evidently premature report in 2010 that Voyager had reached a distance so far from the sun that it could no longer detect solar winds and another in 2011 that it had reached an "outer shell" of solar influence. It turns out that the boundaries of the solar system are fuzzier than once anticipated; the L.A. Times is reporting that "Toward the end of July 2012, Voyager 1's instruments reported that solar winds had suddenly dropped by half, while the strength of the magnetic field almost doubled, according to the studies. Those values then switched back and forth five times before they became fixed on Aug. 25. Since then, solar winds have all but disappeared, but the direction of the magnetic field has barely budged." Also at Wired, which notes "That's hard to explain because the galaxy's magnetic field is thought to be inclined 60 degrees from the sun's field. No one is entirely sure what's going on. ... [It's] almost as if Voyager thought it was going outside but instead found itself standing in the foyer of the sun's home with an open door that allows wind to blow in from the galaxy."
Obligatory XKCD
Unexpected? You didn't think something 4.5 billion years old would have a few wrinkles?
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
Vejur will be back
Someone else (who I think I saw here on Slashdot the last time Voyager was mentioned) had a great analogy for what we're likely seeing. I can't take credit for this at all, but I think it makes a lot of sense.
Suppose we're a small probe, making our way off an island, down the beach, and into the ocean. All we have is a wind-speed detector, and a water detector. As we near the water, waves start lapping over us. When they do, our wind-speed detector says "no wind", and our water detector says "we're wet." Have we entered the ocean yet? The answer is "not quite, but we're really darn close."
It doesn't seem surprising to me at all that the boundary neither perfectly uniform, nor stationary in time. I think we'll be in this transition band for a while.
Program Intellivision!
Our galaxy is 120,000 light years across. Voyager is currently traveling 38,100 miles per hour, or 1/17600 the speed of light. As such, just to cross our galaxy, it would take 211.2 Million years. The Andromeda Galaxy is 2.54 Million light years away. Or if it were pointed towards Andromeda (it's not), it would take 44.7 Billion years to get there. Even traveling at Voyager speeds to Proxima Centari (our nearest star) would take 17600 years to get there. To recap, space is big... Really big.
Thirty four characters live here.
You may think it's a long way down the road to the chemist's, but that's just peanuts to space.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
Motor skills are controlled from the back of the brain, not from the front.
everyone knows how much the glans resembles an apple
Dude, get that checked out by a Doctor, seriously, that sounds problematic.
You do realize that, until very recently, all these creationists were split rather equally between both dems and reps. (The gay marriage and abortion issue pushed white evangelists into the Reps side.) The black population is over 50% creationist (and 90+ are dems) and almost 50% of those who classify themselves as liberal are creationists.
http://blogs.discovermagazine.com/gnxp/2010/05/who-are-the-creationists-by-the-numbers/#.UdBCoDu1H4s
Another thing to think about is that all creationists are not the same. There are they young earthers as well as those who accept that the earth is billions of years old but who think that God created life (and accept minor evolutionary change).
If you're scared of your govt then you need to further restrict its powers
Vote 3rd Party in 2016 and beyond
How far to Milliway's? There is enough time for that, right?
Bitcoin pyramid: Join here: http://www.bitcoinpyramid.com/r/1427 it's FREE!
How do we know it is the same magnetic field affecting V I?
You are not separate from the universe, you're part of it. One of many entities that allows the universe to observe and talk to itself. - Sagan (paraphrased).
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Not the Milky Way. Milliways, the Restaurant at the End of the Universe.
"National Security is the chief cause of national insecurity." - Celine's First Law
I"m trying to remember if we're going faster than our sun at the moment, or slower. Ah, well, not finding a ready reference, however a couple of back of the envelope calculations should work. The planet is in an elliptical orbit around the sun, dictated by gravity, and with no appreciable forces of acceleration affecting the planet that are not also affecting the path of the sun. (Yes that can happen, consider the possibility that the orbit of the earth passes through one of the jets of a supernova, where the jet does not directly interact with the sun. However we'd probably notice something like that, or cease to notice anything else.) Neither do we appear to be generating a field or having any reaction sources that act as a drive. I'm not suggesting that we won't ever find such, but I do not expect that we will, as I think that if the planet were doing this, or affected by such, that again, we would be able to detect it, and the best information I'm aware of doesn't indicate that we have detected such a phenomena.
In this orbit, we vary from leading the sun in it's orbit of the galaxy by approximately one AU, to trailing the sun by approximately the same distance, over the period of a year. An AU is approximately 150 billion meters, so we're looking at an orbit approximately 300 billion meters from trail, to lead. At trail and lead points in the orbit, the speed of the planet around the galaxy matches that of the sun, so the points of interest are where the orbit crosses the plane perpendicular to the orbit of the sun intersecting the line between the sun and the galactic center. These two points are inflection points in the change in apparent acceleration due to gravity where as we are moving ahead of the sun our acceleration starts decreasing, and as we move to trailing the sun our acceleration is increasing.
Now you can apply some trig to get the numbers, but it's just as easy to work out the various speeds by noting that in 6 months, the planet earth travels 300 billion meters relative to the earth, and starts with a relative velocity of zero. At 3600 seconds per hour, 24 hours per day, and 182.5 days per half year, that means that we have 15,768,000 seconds to work with. 300,000,000,000 meters divided by 15,768,000 seconds means that we on average travel 19,025.875, call it 19,026 meters per second over that half a year. To start at zero, and end at zero, that means that at the inflection points, were traveling som 38,051 meters per second faster, or slower than the sun. Call it 38 kps. (approximate) The speed of light is some 300,000 kps, so our change in velocity is just over 1/10000'th of the speed of light for that half of the orbit, or twice that 1/5000th of the speed of light for the entire orbit.
Consider the estimated distance out from the center of the galaxy that we are at, and the fact that in the presumed lifespan of the sun, just over 4.5 billion years, calculations show that the sun has made some 12 orbits of the galaxy, (i.e. approximately 300 million years per orbit) and it's trivial to show that you really don't need to 'compensate' for the orbital speed of the sun around the galactic center.
To add to the interest, I'll leave it as an exercise of the reader to discover what the change in velocity for Mercury, and Jupiter (starting point, mercury has an orbit of approx .4 au, and a period of approx 88 days, while Jupiter has an orbit of just over 5 au, and a period of 4331 days, or just under 12 years.) Which you should see that having an orbit closer to the sun results in having a _lower_ change in velocity relative to the sun, not a higher. i.e. to put a solar probe into an orbit closer to the sun, you actually need to slow down the orbital velocity of the probe, not increase it's speed. You do Accelerate the probe, however that acceleration is 'negative' with respect to it's existing orbital speed about the sun.
You never know...
Plutonium lasts for quite sometime, however yes the radioisotope thermoelectric generators on board are losing wattage year over year as that plutonium decays. In 2 years, the probe will no longer have the power necessary to record it's data for transmission, and in 12 years will no longer have the power necessary to run any of its scientific instruments. It's main systems will still be able to run for decades though due to much lower wattage requirements, but without being able to provide any readings, record data or transmit it back it will be essentially dead.
Thirty four characters live here.
You left out the Deists, who believe that God created the universe and left it to evolve. (IIRC they never actually said that God created life, and they didn't talk about evolution, but then they were prominent before Darwin.)
OTOH, I'm not sure how many Diests are around anymore.
I think we've pushed this "anyone can grow up to be president" thing too far.
It reminds me of my kids:
Kids: "Are we there yet?"
Me: "No."
Kids: "Are we there yet?"
Me: "No! Stop asking!"
Kids: "Are we there yet?"
Me: "I don't know, we are hell fucking lost!"
Kids: "Dad, you shouldn't cuss."
Me: "Shuddup! I'm trying to concentrate!"
Table-ized A.I.
So you're telling me there's wrinkles outside Uranus ?
Normally I ascribe all life to intelligent design, but in your case I'll make an exception.
You must be joking. Why on earth would you use a complicated OS like Linux for something that just has to do one very particular job? And then have some hacker take control of it because they found a vulnerability in one of the services the probe was never intended to use anyway? Or the software crash because of some mysterious bug in some library written by some guy in his parents' basement 10 years ago?
I remember video players (tapes, early discs) that would start playing pretty much immediately after you switched them on. Nowadays, you switch on a DVD/blueray player and you get "Welcome" for about 20 seconds. Then the thing crashes every now and then so it needs a reboot. Yep, it's running some flavor of Linux. If you need reliability and efficiency, I'll take 70's technology any time.
Just program the thing directly for whatever it needs to do, using proprietary code. The code will be 1% the size and a lot more efficient.
(Not that I don't like Linux, by the way. It's great for general purpose equipment where you might actually need all of those capabilities)