I bet you Al Gore claims this is of he and Tipper. THEN he would go on to invent the internet
Posted on 02/25/2003 4:51:06 PM PST by HAL9000
LOS ANGELES (AP) - Pioneer 10, the first spacecraft to venture out of the solar system, has fallen silent after traveling billions of miles from Earth on a mission that has lasted nearly 31 years, NASA said Tuesday.What was apparently the spacecraft's last signal was received Jan. 22 by the Jet Propulsion Laboratory's Deep Space Network. At the time, Pioneer 10 was 7.6 billion miles from Earth; the signal, traveling at the speed of light, took 11 hours and 20 minutes to arrive.
The signal and the two previous signals were very faint. The Deep Space Network heard nothing from Pioneer 10 during a final attempt at contact on Feb. 7. No more attempts are planned.
Pioneer 10 was launched March 2, 1972, on a 21-month mission. It became the first spacecraft to pass through the asteroid belt and the first to obtain close-up images of Jupiter. In 1983, it became the first manmade object to leave the solar system when it passed the orbit of distant Pluto.
Although Pioneer 10's mission officially ended in 1997, scientists continued to track the TRW Inc.-built spacecraft as part of a study of communication technology for NASA's future Interstellar Probe mission. Pioneer 10 hasn't relayed telemetry data since April 27.
"It was a workhorse that far exceeded its warranty, and I guess you could say we got our money's worth," said Larry Lasher, Pioneer 10 project manager at NASA's Ames Research Center.
Pioneer 10 carries a gold plaque engraved with a message of goodwill and a map showing the Earth's location in the solar system. The spacecraft continues to coast toward the star Aldebaran in the constellation Taurus. It will take 2 million years to reach it.
On the Net:
Pioneer 10: spaceprojects.arc.nasa.gov/Space_Projects/pioneer/PNhome.html
You had better sign up for a good calling plan quick 'cause... damn.
Damn, but I think that I'll probably miss it.
I believe the operative word is "talked". He's been dead for billions and billions and billions of seconds.
I bet you Al Gore claims this is of he and Tipper. THEN he would go on to invent the internet
Not to be real picky, but how does a signal travel the speed of light.
Is this a typo or is the signal sent on a light beam? If it was, I never heard of that before
If a tree falls in the forest and no one hears it....
Naah.. there will be pirated copies all over the universe in short order.
The state of the Big Trak is good. It's actually the platform for an autonomous vacuum cleaner project. I am using it to test sensors and get the programming squared away.
I wish I knew someone with a trashed Rainbow I could examine to guide me here or a Rexair serviceman who could hook me up with parts or let me see some exploded diagrams of the various models. Damn. They guard this stuff like it's nuclear secrets or something!
(Vacuum cleaners ain't my specialty, so I need allot of help in this department.)
I was at JPL working in the control room for the Magellan Spacecraft. The actual data rates (X-band) were 268.8 or 115 kbps. Remember data rate from a satellite is usually posted in Bits/sec since data is serially downlinked. One other interesting fact was that the same dish antenna used to collect the SAR data was the same one used to transmit the data back to earth. The following is a brief synopsis of how telemetry is sent from a spacecraft back to the ground.
First what is telemetry?: Telemetry is the process of conveying information by transmitting information from one point to another. The Merriam-Webster dictionary term for telemeter is “transmit (as the measurement of a quantity) by telemeter”. In other words it is a process of conveying information, such as voltages and temperatures, from a remote location to another for subsequent data analysis or interpretation.
On the average spacecraft (I should give a distinction here, spacecraft are either manned or are no longer orbiting the earth, such as an interplanetary, and satellites are unmanned earth orbiters) there are hundreds, possibly even thousands of individual items (including mission data) that need to be transmitted from the vehicle to a ground station for analysis such as a voltage, temperature, attitude and the like.
It is impractical if not downright impossible to simultaneously transmit all of this data to a ground station. So the data is ”injected” into a serial telemetry stream that only requires one (or possibly a few) links between the vehicle and the ground. This process of inserting all of this data in a specific pre-determined pattern is called commutation.
To do this, the data must be digitized (i.e. converted to ones (1s) and zeros (0s). Due to fidelity reasons, link margin, and communications bandwidth, many of these parameters are sent down as an 8 bit (8 serial 1s and 0s) "word". Without going into the math here, this converts into 0 thru 255 decimal or the number 0 thru FF in hex. Usually these values are called Engineering Units (EUs).
If all data is lost, the number either reverts to 0 or 255, which usually is an out-of-limit condition.
All the telemetry monitors are "gathered" as digital words and injected into the telemetry stream one at a time. The problem is figuring out how to pull that stream of ones and zeros back apart on the ground. So every so often a known set of bits, specific pattern such as "fdc0f1hex" (nonsense number I just made up) is inserted into the stream so the ground decommutator can "pull" the data back apart and "read" the individual words. This known "word" is what is synced up on and is called the frame sync.
We can further sub-divide this telemetry stream into sub frames with a counter or a sub-frame sync to allow greater flexibility in how the parameters will be downlinked. Lets say we are doing something special, like running the robotic arm on the Shuttle. The telemetry stream has a finite space, so using a different set of sub-frames, we can downlink more data at that moment on the arm than our normal State-of-Health (SOH) telemetry monitors.
Rememer, there may be more than five thousand (5000) individual monitors that can be sent to the ground. The trick is, which ones and at what time during the mission should they be sent.
One of the largest data rates I ever worked with was 320 million bits/sec.
"Job security" others would answer
Actually one of the things that we were hoping to find was the Heliopause of our solar system.
Well, I like the Rainbow water trap.
I can copy it and it's no big deal since it's not a commerical item. Just a project.
With the water trap, an IR beacon and barcodes on the walls it can find it's way back, recharge, change the water and re-deploy.
Plus they spray pretty smelling stuff and all kinds of neat things.
Radio is the same "stuff" as light, just at a lower frequency.
Yes it is! As with the Apollo program, NASA at its best...
I love working at JPL. :-)
Thanks, I never knew that.
I always thought radio signals traveled at somewhere below the speed of light.
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