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Voyager 1 Exits Our Solar System
eldavojohn writes "The first man-made craft to do so is now entering a 'cosmic purgatory' between solar systems and entering an interstellar space of the Milky Way Galaxy. With much anticipation, Voyager 1 is now 'in a stagnation region in the outermost layer of the bubble around our solar system. Voyager is showing that what is outside is pushing back.' After three decades the spacecraft is still operating and apparently has enough power and fuel to continue to do so until 2020. The first big piece of news? 'We've been using the flow of energetic charged particles at Voyager 1 as a kind of wind sock to estimate the solar wind velocity. We've found that the wind speeds are low in this region and gust erratically. For the first time, the wind even blows back at us. We are evidently traveling in completely new territory. Scientists had suggested previously that there might be a stagnation layer, but we weren't sure it existed until now.' This process could take months to years to completely leave the outer shell but already scientists are receiving valuable information."
Wasn't the Oort cloud supposed to be the edge of the Solar System, and that's still a few trillion miles off.
It's really really cool that Voyager is still going, but this talk of crossing into the heliosheath, etc seems to be dragged out a bit (yes, it's a vague and slow transition, I understand...)
http://science.slashdot.org/story/05/05/24/2334240/voyager-1-crosses-the-termination-shock
http://science.slashdot.org/story/11/12/02/0243246/voyager-probes-give-us-ets-view
http://science.slashdot.org/story/10/12/14/1451216/voyager-1-beyond-solar-wind
http://science.slashdot.org/story/11/04/28/2314203/voyager-set-to-enter-interstellar-space
Voyagers transmitter uses a pencil type vacuum tube in the final amplifier. At the time they were designed there were no transistors that could operate at the required frequency and power level and also withstand the expected cosmic radiation in space. Tubes were the ONLY devices RAD hard enough to do the job.
Since then RCA has quit making tubes (and a lot of other stuff as well).
"Space is big. Really big. You just won't believe how vastly, hugely, mindbogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space, listen..." -HHGTG
I am officially gone from
It's even more alarming because Voyager is 11 billion miles away and still might as well just be down the corner getting a pack of smokes in terms of its location relative to known concentrations of anything. 1.1*10^10 miles is a lot; but the nearest extrasolar star system is on the order of 2.5*10^13...
With updated equipment, high resolution sensors/ cameras.... heck even put on a hubble like telescope while we're at it... a dozen of these in all directions.... that would definitely kick ass... >
Never antropomorphize computers, they do not like that
The amazing thing (well, one of the amazing things) about the Voyager program is the communication link. Voyager's signal, as received on Earth, is almost unbelievably weak.
One can use the Friis Transmission Equation to see just how weak the signal from Voyager 1 is at the moment:
Pr = Pt * Gt * Gr * (lambda/(4 * pi * R))^2, where
Pr is received power, in watts;
Pt is transmitted power, in watts;
Gt is the gain of the transmitting antenna, relative to an isotropic source (a unit-less value);
Gr is the gain of the receiving antenna (one of the 70m DSN antennas), relative to an isotropic source (a unit-less value);
lambda is the operating wavelength, in meters, and equal to c/f, or very close to 300/fM, where fM is the operating frequency in MHz;
and R is the range (distance) in meters.
Pt = 18 watts (assuming this hasn't degraded over time and distance);
Gt = 48 dBi, or about 63100;
Gr = 74 dBi, or about 25.1*10^6;
fM = 8420 MHz, so lambda = 300/fM = 0.0356 meters; and
R = 17,545,000,000 km, or 1.75 * 10^13 meters.
Grinding all this out, one is left with a received signal strength -- at the terminals of a 70-meter dish, mind you -- of:
Pr = 18 * 63100 * 25.1*10^6 * (0.0356/(4 * pi * 1.75 * 10^13))^2 = 7.45 * 10^(-19) watts, or 745 -- wait for it -- zeptowatts.
This is equal to -181.3 dBW, or -151.3 dBm. (I don't know how many Libraries of Congress that is.)
In the year 2020, when the probe's power generator is expected to expire, the probe will be about 2 * 10^13 meters away from Earth; using the same calculation the signal will have weakened slightly, to 5.73 * 10^(-19) watts, or 573 zeptowatts, -182.4 dBW, or -152.4 dBm.
(Unless I've made some trivial calculation error, of course.)
Voyager are not the only ones.
Pioneer 10 and 11 were both launched with sufficient velocity to escape the solar system. They were launched before Voyager, but did not have as large a velocity, so were passed by the Voyager probes in the 1990s as the furthest from the Earth.
I'm pretty sure this was planned, since the Pioneer probes has this really cool plaque on them (designed by Carl Sagan), in the event they were found by alien species:
http://en.wikipedia.org/wiki/Pioneer_plaque
While that's true for many types of things, ABC News has been doing a Made in America series for most of this year. (I've only seen a few of the reports when reaired on World News Now.) They've found lots of things made in America, and some was cheaper than the foreign made stuff. I don't remember all of the examples, but toys, furniture, cooking implements were some of them. (The most recent report I saw was a followup where the Bundt pan factory hired a few more people, at least partially because sales had gone way up since the last report.)
As others have said in past discussions of this type, what do you call a Toyota made (assembled/built) in Kentucky? Is that an American car or a foreign car?
I disagree with your main premise, but if you want "American made", you can find it, at least for many things.. but you'll sometimes have to pay more, and definitely will have to look harder.
The successor to Voyager I was built a few years ago -- it's called New Horizons. Launched in 2006 and halfway to Pluto right now. Proudly Made in USA. Tell me about superior Chinese tech when they send something to Pluto.
"The fact is that consumers killed US manufacturing" The US is still ranked the #1 manufacturer in the world.
This level of quality exists for almost anything you would care to buy. These items costs a bit more and they don't carry them at Walmart, but that doesn't mean they don't exist.
Congratulations, you've just discovered the Sam Vimes' Boots theory of wealth.
TL;DR: Only the rich can afford to save money.
Crumb's Corollary: Never bring a knife to a bun fight.
You've clearly never seen a proper cheap CRT. Yes, compared to bottom-of-the-barrel TN TFTs they would still have been better when new but with ten years and some age-induced blurring on them even a cheap TN panel will be easier on the eyes.
Of course, I've been using IPS monitors for years (and CRTs are a pain, you need a vertical refresh rate of at least 75 Hz for them to be usable and even then there are all sorts of other issues which are not cancelled out by "It's got blacker blacks than a TFT!!11one").
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