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Farthest Human-Made Object: First Quarter Century
An anonymous reader writes "The NASA Astrobiology Magazine reports today the 25th anniversary of the Voyager I launch, now the farthest human-made object at 93 Sun-Earth distances (93 AU), or 12 light-hours away. Expected battery life to 2020. The fascinating part is that gold record of civilization, which is a strange audio mix of sentimental kisses [wav file, let ET phone home that way] and perhaps the most dated picture of DNA. Some progress there. Voy 1 will likely confuse even modern earthlings-- much less ET. Case in point: In 2002, can we understand that 70's show, when the Polish greeting memorialized as "Welcome, creatures from beyond the outer world"? Unlike those ET creatures we meet daily from the inner world?"
Assessing their key radio-isotope generators that power the on-board battery, Massey evaluates: "We don't run out of electrical power until about 2020", or at least for Voyager I, around 43 years towards its lifetime of some communication with its originating star, Sol, and its home planet, the Earth.
Looks like the isotope's power the battery.
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Ok, I got off (actually, stayed on) my butt and found this:
Radioisotope Thermoelectric Generators (RTG's)
Three RTG's provide electric power to Voyager. The generators produce about 1800 watts of heat by the radioactive decay of plutonium. The heat is then converted to about 400 watts of electric power by thermocouplers. The RTG's are mounted on a boom to protect the scientific instruments from excess heat and radioactivity.
and this, which discusses RTGs in the context of Cassini and safety.
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Doesn't the disc on Voyager feature an introduction by then UN Secretary General Kurt Waldheim giving greetings from Earth?
How odd that the first human voice any aliens who could work the disc will hear is the voice of a former Nazi alleged to have taken part in war crime atrocities in the then Yugoslavia...
"Information wants to be paid"
Besides, your analogy falls flat. I presume your point was that the age of the technology is irrelevant when it comes to leaving the solar system? Then consider this: what is it that pushed the 1970s technology of the Voyagers out of the solar system? Answer: more 1970s technology. If your 16th century vase were propelled by 16th century rockets, then your analogy would be valid.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
The power source on the Voyager I & II spacecrafts, like most other of the time, is called a PTG or plutonium thermoelectric generator. Basically you have a heat source (chunk of plutonium) surrounded by devices similar in construction to modern peltier coolers. The Seebeck effect (opposite of Peltier effect) allows electrical power to be generated by the temperature gradient across the device. Basically you have an electrical power source with no moving parts and a very long life (Plutonium has a decently large halflife). It's a shame that the environmentalists had a hissy fit in the 80's and 90's that blocked this very reliable technology from being used on modern spacecraft.
All I hear is "Wytajcie, istoty zaswiatu," which would basically mean "Greetings, otherworldly beings," or better, "Greetings to beings from beyond Earth." The "outer world" is at best a rather poetic (or possibly condescending) translation.
I think it would be an equivalent of "Greetings, creatures from Outer Space," but they didn't intone it pretentiously, right before Ed Wood hovers the hubcap from a string and a theremin plays in the background as his boustier intrudes into the picture, as we are wont to do over here.
The heliopause is not a gravitational feature. It is a feature of matter.
The sun emits a flood of mostly-charged particles that make up the "solar wind." The earth is shielded by its magnetic fields, but the interplanetary environment is quite harsh.
The heliopause is where this outward flow of solar matter becomes less than the general flow of matter through the galaxy. There isn't any good way to observe this from earth, which is why having a Voyager pass through the area is a good thing. Our current picture of the heliopause is based on physical modeling and simulation. Having any observational data to check these models against would be a major step forward.
"Project Thunderwell" is a bit of a myth.
See This page for details about the real test (search for "Pascal-B").
Escape velocity from the Sun at a given radius,r, is just sqrt(2*G*M_sun/r). Plugging in (G=6.67e-8 in cgs units; M=2e33 g; r=93 AU = 93 *(1.496e13 cm)), I get v_escape of about 4.4e5 cm/s, or 4.4 km/s. (About 15,800 km/hr, or 9800 mi/hr, safely less than Voyager's velocity.)
It was an interesting thought, though. :-)
I used to own the hardcover, but it disappeared one day, along with my copy of A House in Space , the story of the first space station, Skylab.
Nothing for 6-digit uids?