Some questions on the basic hardware of the Voyager spacecraft:

1. From which material was the decahedral space bus made ( Aluminium ? )
2. Exact weight of the spacecraft - literature gives numbers between 792 and 825 kilograms ?


Some additional questions:

1. The Deep Space Network of worldwide antenna sites wasn't sufficient to collect the faint signal of the distant spacecraft once beyond Saturn ... I know that the twenty-seven 25-meter steerable radio antennes of the Very Large Array in New Mexico were linked with DSN ... when was this done exactly?
( 1989 Neptune encounter only ? )
2. What is the actual telecommunications time-lag 1-way to Earth (after having passed the bow-shock )

As far as telecoms delay is concerned, Heavens above site says one-way light time for Voyager 1 is currently 13.66 hrs and Voyager 2 10.99 hrs.

Check out the Voyager Neptune Travel Guide, much more than a press kit:

http://ntrs.nasa.gov/archive/nasa/casi.ntr..._1990004096.pdf

and the current status reports:

http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm

Also interesting if you have read the Travel Guide and know what DTR, PWS or CCS means:

http://voyager.jpl.nasa.gov/mission/soe-sf...g_schedule.html

Have fun!
Analyst

Thanks, are there any High-resolution Voyager spacecraft images online (BOth NASA-JPL and NASA-KSC only post normal resolution artist impressions of the Voyager hardware )

I only have the NASA-JPL artist impression P-23836A showing Voyager 2 near Uranus, but scanning from a glossy litho doesn't give good results

Spacecraft 1820 p, including 231 p science instruments (=825,53 Kg)
Propulsion module (SRM) 2690 p
Total including adapter to centauer upper stage 4630 p

This gives 120 p for the adapter.

Source: Dethlolt, H.C./Schorn, R.A.: To The Outer Planet's And Beyond, Voyager's Grand Tour, Washington, London 2003.

The authors are citing: NASA news releas No. 77-136 (Voyager Press Kit). Does anyone has a link?

Analyst

[quote=PhilCo126,Jan 3 2006, 08:32 PM]
Thanks, are there any High-resolution Voyager spacecraft images online (BOth NASA-JPL and NASA-KSC only post normal resolution artist impressions of the Voyager hardware )

Not very high res, but I have a couple Voyager mockup 3D images at this page:
http://www.donaldedavis.com/PARTS/3DPHOTOS.html

I have taken many digital photos of the Von Karman auditorium Voyager spacecraft mockup, let me know what angles you would like and I'll dig them up.

Don

Only some gif images labeled "unknown" ( = no NASA photo-number )
http://voyager.jpl.nasa.gov/image/assembly.html

Amazing pictures, Phil.
Can someone explain why the dark color of the blankets, contrary to the usual gold cover? Which material they used?

Is the Von Karman auditorium Voyager spacecraft really a mockup? I was always under the impression that it was Voyager 3.

JPL started using black thermal blankets on Mariner 4. They had had many issues with thermal control on Mariner 2.
From the paper "Mechanical evolution of the Mariner spacecraft" by J.N. Wilson (1966)
"Although the black shields absorbed more solar energy than did the Mariner II white shields, the uncertainty in the amount of energy absorbed was less. Increased layers of insulation allowed the total heat transmitted through the shield to be reduced to a minimum"

First I would like to thank those UMSF forum-members who contacted me off-forum... Here I'm sharing another 'artwork'

Grazie, Paolo!
Is a strange motivation, anyway I like very much this black dressing: it looks somewath alien today!

Here's another small resolution view of the Voyager in black blankets in the space simulation chamber. Notice the position of the booms

Sharing an amazing view of the check-out of Voyager's 13 meter long magnetometer in fully extended position. In space, with "zero gravity" conditions, the triangular epoxy glass mast spiraled from its housing and provided a rigid support for the two magnetometers at mid-point and far end of the boom, seen here above the test equipment.

The dual magnetometer set was an innovation pioneered by Mariner 10, where it would have taken a significant fraction of the very small mission budget to produce a "magnetically clean" spacecraft. The mid-way mag detects approximately the same spacecraft induced field as the outer mag, but at several times the field strength. Both instruments detect the same exterior field. As spacecaraft powere is switched on and off to different equipment, scan platforms and scanning instruments scan, etc, the difference between the two calibrates the spacecraft field component accuratly so it can be eliminated.

Oh well... May I ask more questions?

1. The 16 hydrazine engines of Voyager -- were these all of the 0.2 lbf MR-103H type or the four TCM engines were of a larger thrust?
2. What was the initial velocity of V2 and V1 after separation with the Star 37E kick-up motor?

Interesting - I guess the gold-foil stuff (and the aluminized mylar) have advantages more for
reproducibilty/relibaility than performance/cost specifically - paint is notoriously hard to get right (qv
the overheating problems with Genesis - see Space Systems Failures by Harland and myself)

There is of course the old joke

"Why does JPL make all its spacecraft gold-plated ?"
Because pure gold is too heavy....

Noticed Part II is on the Voyager computers, so it belongs in this Voyager hardware topic
http://history.nasa.gov/computers/contents.html

I was wondering if anyone knew the memory capacity & specs of the Digital tape recorder (DTR) onboard Voyager? I can't find it on the usual NASA sites. I know that they uploaded new image compression software on one of the "spare" 1802 processors for the Uranus/Neptune flyby to increase the number of images captured and save DSN time. Are there JPG type artifacts on those images, or was it just lossless RLE/Huffman type encoding?

I've got some infos 'sci44'. There are from JPL Publication 89-24, june 1,1989 "The Voyager Neptune Travel Guide".
"The DTR has three speeds in use at Neptune encounter (...) 115.2 Kbps (record only), 21.6 Kbps (playback only) and 7.2 Kbps (both record and playback). There are 8 tracks on the DPR. Each of these can hold 12 images if only images are recorded" (...) "It's important to play back quickly so that the tape recorder can be filled again. But, playbacks interfere with science gathering and require certain DSN configurations that are not always available".
I hope it helps.

Thanks for that - so the DTR can hold 8 tracks, 12 images per track. I wonder if thats with compression, or uncompressed? If uncompressed, well each image is 256 x 256 x 8 bits (256 grey scale) = 64K. 8 x 12 x 64 = 6144k, or 6 megabytes at a guess. That means next time you go out and take a picture with your new camera, just 1 picture at a high resolution is equal to all the data storage Voyager 2 had available during its Jupiter/Saturn/Uranus/Neptune flyby! Now as I said, they did implement better compression for the Uranus/Neptune flybys - I have to assume simple run-length compression for those old 1802's. If you look at the raw Cassini images, you will see a "comb" like effect - run length compression is applied to scan lines in pairs, but at the point where it fills up available space, the alternate vertical pixel is dropped. Is the same compression applied to Uranian/Neptunian images? Are there "Raw" images anywhere?

http://www.goldenrecord.org/

That's an awesome site. I tried to find a copy of the CD-ROM, but was stymied, so this was a nice substitution treat. (I did manage to locate a copy of the hardback book.)

I did a little digging to find out why the record is plated with gold, but didn't find any definitive information. Is it just because gold is shiny and might attract the attention of anyone examining the spacecraft, saying, "Hey! We, the people who built this emissary, value the contents of this box! Pay close attention to (possibly worn) diagrams."

I've always thought of gold as being very soft, and therefor not exactly ideal material to withstand space travel and its variety of unmitigated rigors.

Whether the material is gold or titanium doesn't make much difference when you're traveling 17 kilometers per second and run into a dust particle!

Gold is very resistant to corrosion (like from atomic oxygen in LEO, or in this case prolonged passage though an interstellar gas cloud), and an excellent conductor of both heat & electricity (therefore resistant to spot-arcing or uneven thermal flex). It's a good material for this application.

Per Voyager Backgrounder ( NASA Release No. 80-160, http://ntrs.nasa.gov/archive/nasa/casi.ntr..._1981001583.pdf ), DTR is a 0.5 in by 328 meters 8-track magnetic tape recorder capable of storing 536 million bits. 96 images may be stored on it.

Well, replying to myself.
Per Voyager Backrounder, Voyager Mission Module has 16 x 0.2 lbf thrusters, four for trajectory corrections and 12 (in two redundant branches) for attitude control. I guess these are of MR-103 family; which version exactly?
Then, Voyager Propulsion Module has 4 larger thrusters for pitch and yaw control, these were 100 lbf items of MR-104 family -- which excactly? -- and 4 smaller ones for roll control with a thrust of 5 lbf. I couldn't find the designation for these.

This seems like an appropriate thread to post this in — here are several archive clips showing the Voyager spacecraft in various stages of construction:

http://www.footagevault.com/clip/FTV-0001398
http://www.footagevault.com/clip/FTV-0001399
http://www.footagevault.com/clip/FTV-0001400
http://www.footagevault.com/clip/FTV-0006097
http://www.footagevault.com/clip/FTV-0006099
http://www.footagevault.com/clip/FTV-0006205

A NASA film called "Project Voyager" can also be found on the FootageVault website:

http://www.footagevault.com/clip/FTV-0006211
http://www.footagevault.com/clip/FTV-0006212
http://www.footagevault.com/clip/FTV-0006213
http://www.footagevault.com/clip/FTV-0006214
http://www.footagevault.com/clip/FTV-0006215

Of interest is the primitive animation of a "possible" encounter with Uranus, where the rings are noticeably absent, given that they had yet to be discovered at the time this documentary was produced!

Found it and just uploaded to the NSF forum: http://forum.nasaspaceflight.com/index.php...0;attach=591860
(6 Mbyte -- too large to upload here)