ISEE-3 Satellite Is Back Under Control

brindafella writes: "Over the last two days, the (Reboot Project for the International Sun/Earth Explorer 3 (ISEE-3) satellite has successfully commanded ISEE-3 from Earth, using signals transmitted from the Aricebo Observatory. Signals were also received by cooperating dishes: the 21-meter dish located at Kentucky's Morehead State University Space Science Center; the 20-meter dish antenna in Bochum Observatory, Germany, operated by AMSAT Germany; and SETI's Allen Telescope Array, California. ISEE-3 was launched in 1978, and last commanded in 1999 by NASA. On May 15, 2014, the project reached its crowdfunding goal of US$125,000, which will cover the costs of writing the software to communicate with the probe, searching through the NASA archives for the information needed to control the spacecraft, and buying time on the dish antennas. The project then set a 'stretch goal' of $150,000, which it also met with a final total of $159,502 raised. The goal is to be able to command the spacecraft to fire its engines to enter an Earth orbit, and then be usable for further space exploration. This satellite does not even have a computer; it is all 'hard-wired.'"

Comments

Congratulations!

[Anonymous Coward]

I had written off this project as an impossible dream. Glad to say I was wrong.
This is an awesome accomplishment.

hard-wired can be a computer

[Virtucon]

This satellite does not even have a computer; it is all 'hard-wired.'"

A lot of early computer systems were hard-wired in terms of instructions and logic paths. It didn't make them unusable, just arcane considering newer technologies like SoCs. We have come a long way.

Re:hard-wired can be a computer

[brindafella]

Yes, I understand what you say. In this case, there is no "computer in the middle", just hard-wired resistors, capacitors, inductors, etc. That the Reboot Project has found it to be active and responsive is VERY exciting to an old-school electronics person like me. :-)

Re:hard-wired can be a computer

[Charliemopps]

This satellite does not even have a computer; it is all 'hard-wired.'"

A lot of early computer systems were hard-wired in terms of instructions and logic paths. It didn't make them unusable, just arcane considering newer technologies like SoCs. We have come a long way.

Right. It has no integrated circuits. There's no way it doesn't have a computer. It couldn't receive signals and fire its thrusters otherwise. If there are no IC's out there that do what you need (which I assume is often the case with space craft) there's not much need for them. A lot of electronics I've built in the past has been simple enough that I did what we always called "Point to Point" meaning you have a board (like real wood!) with holes drilled into it, or metal posts... and you solder your components "point to point" with each other. There aren't even wires.

Here's a random image I found as an example: http://bgmb55.files.wordpress....
You use the physical shape of the component to design your board. There are often components on both sides of the board.
This doesn't lend itself well to very complicated circuits however. If you get too many components going, you can easy create a short hazard for yourself. But it makes simple circuits a lot easier to build and maintain. It also makes each components function a lot easier to understand at a glance. This picture is clearly a Tube Amplifer for example. You can see that just by glancing at it (and the tube sockets help to)

Re:hard-wired can be a computer

[Jaime2]

Right. It has no integrated circuits. There's no way it doesn't have a computer. It couldn't receive signals and fire its thrusters otherwise.

A collection of discreet electronic components hardly qualifies as a computer. Receiving radio signals was something done long before the first computer was invented.

Re:hard-wired can be a computer

[PPH]

'Computer', 'hard-wired' and 'integrated circuit' are unrelated. There were computers which were programmable but had no ICs (some even had vacuum tubes). There are also hard wired systems, complete with modern CPUs in use today (stretching the definition of hard wired). In the past, these were programmed by burning open fusible links on the chip, so they were for all intents and purposes 'hard wired'.

Re:hard-wired can be a computer

[mmell]

Perhaps you'd better define what you mean by 'computer'. Computers existed before solid-state circuitry, and long before LSI (Large Scale Integration, or more commonly 'integrated curcuit' electronics).

Re:hard-wired can be a computer

[Jaime2]

It doesn't really matter. I was responding to a statement that said that if something receives signals and fires thrusters, then it must be a computer. Any definition that broad would be indistinguishable from "circuit" and would make the word "computer" redundant. I hate it when language evolves to a point where it's hard to express thoughts accurately.

This is the same problem I have with people accepting the phrase "I could care less" as meaning "I don't care". It makes language much harder to use. Imagine trying to explain the meaning of that phrase to someone learning English, they would come away thinking that each collection of words has some fungible meaning that is totally separate from the meanings of the individual word and the rules or grammar.

Re:hard-wired can be a computer

[Megane]

I think you could say that it uses the discrete components equivalent of an ASIC or FPGA.

Re:hard-wired can be a computer

[Charliemopps]

You're basically declaring yourself a pedant.
Not only that, you're also completely wrong. Even an Abacus is considered a computer.

But let's just assume you want to use the more popular definition of the term:

computer - an electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.

So we look at ISEE-3s' Wikipedia entry and viola:

ICE carries 13 scientific instruments to measure plasmas, energetic particles, waves, and fields. As of May 2014, all but one are thought to be functional. A data handling system gathers the scientific and engineering data from all systems in the spacecraft and formats them into a serial stream for transmission. The transmitter output power is five watts.

It would be virtually impossible to put anything into space that didn't have some sort of computer on-board.

Have fun correcting my spelling. I could really care less. ;-)

Re:hard-wired can be a computer

[dpidcoe]

This picture is clearly a Tube Amplifer for example.

Well.. if you say so I guess.

Personally I was going to chalk it up to some kind of art project where the artist was attempting to spell out letters in a different language using random electrical components as the medium.

depends on definition of "computer"

[iggymanz]

some gates and circuits to detect and act on series of correct "control tones", the old definition of computer was anything that had input, transformed information, and presented to output (like analog computer, for instance).

Many young-uns think a "computer" needs to be a certain type of digital system with CPU, memory, IO bus and ports, etc.

As a young teen I read the manuals for a (defunct) satellite old retired engineer had, funny as electronics hobbyist I could understand it.

Re:depends on definition of "computer"

[brindafella]

> As a young teen I read the manuals for a (defunct) satellite old retired engineer had, funny as electronics hobbyist I could understand it.

:-) I've been there, too. My first computer was an IBM 1130, with 8kB of 'ram'. From what I can tell, here, we have 0kB and all hard-wired to the devices attached to the receivers and transmitters. The satellite just 'talks' via the transmitter and Earth has to listen, or lose the data. That is "how it was" in 1978 (earlier for the finalisation of the design, and the satellite's set-up of the NSA Deep Space Network ground stations).

Re:depends on definition of "computer"

[brindafella]

Of course, that should read "NASA".

I do not presume that the satellits has been the other ageny of the USA government. ;-)

Re:depends on definition of "computer"

[brindafella]

I really SHOULD check my posts before okaying them!

It is a dark room and I do not touch-type.

Re:depends on definition of "computer"

[drainbramage]

You are likely to be eaten by a Gru.

Re:depends on definition of "computer"

[GTRacer]

Why would a one-time supervillain wannabe turned adoptive father want to eat a poor, endarkened Slashdotter?

Re:depends on definition of "computer"

[NoImNotNineVolt]

Curently, GP's score stands at 4, Interesting:
50% Interesting
30% Overrated
20% Informative

I don't see any troll mods. Are you sure you replied to the correct post?

Re:depends on definition of "computer"

[iggymanz]

yes, before 1935

Arecibo Observatory

[Anonymous Coward]

It's the Arecibo Observatory, not "Aricebo". Does it hurt to check the spelling?

Holy good gravy...

[MrLogic17]

I thought this was all an idealistic dream of some space nerds.
It looks like they just might pull this off ! I'm seriously impressed!

And as for not having a computer on board - that probably greatly increases the odds of it working after all these years. Space is harsh on electronics...

Re:Holy good gravy...

[Anonymous Coward]

I thought this was all an idealistic dream of some space nerds.

It was. Competence and hard work turns idealistic dreams into reality.

+1 Engineers.

Obligatory XKCD...

[johanwanderer]

http://xkcd.com/1337/

Re:Obligatory XKCD...

[Yenya]

Maybe this one will be next:
http://xkcd.com/695/

Crowdfunding eh?

[VIPERsssss]

Maybe we can get it to broadcast Reading Rainbow and give the curmudgeons something to complain about for the next news cycle.

Re:Bravo!

[Nightwraith]

It was certainly nice that this was approved with a great deal of speed by all the agencies involved. Good news too that they were able to preempt other previously approved projects.

But in reality, it sounds like they had an excellent plan and at least some proof-of-concept design done when it was pitched to those agencies. Also, it's pretty time-sensitive and a great PR win if it succeeds, which the space industry desperately needs right now.

When the grease is available, all those wheels of government can turn pretty quickly!

Re:Bravo!

[NatasRevol]

$159k doesn't buy you much grease, at least government grease.

Aw, crap!

[Anonymous Coward]

I did my Ph.D. thesis on data from one of those ISEE-3/ICE detectors. Now I guess my thesis adviser will be all over my ass again to process the new data!

Avoided moon impact as well

[Dishwasha]

As a proud contributor to the ISEE-3 reboot project, I'd like to highlight that after communicating with the satellite, they discovered that the trajectory was over 200,000 km off where the predictions indicated it should be and its trajectory was specifically placing it in danger of impacting the moon. I would like to congratulate the ISEE-3 team on helping avoid a man-made impact with our moon.

(double post due to not being logged in)

Re:Avoided moon impact as well

[amorsen]

I would like to congratulate the ISEE-3 team on helping avoid a man-made impact with our moon.

I am glad that the satellite was saved. However, why is it good to avoid man-made impacts with our moon?

Re:Terminology

[Anonymous Coward]

So, if its orbiting the sun its a ...... planet?

Shhhh. Don't tell Pluto.

Re:Avoided moon impact as well

[NoImNotNineVolt]

I don't get it.

I hate to point this out, but...

[mmell]

Earth is often described as a satellite of Sol. Technically, Sol C.

As noted elsewhere, don't tell Pluto. It's still a satellite of Sol (Sol I). It was stripped of planet status for trolling.

Re:Avoided moon impact as well

[Anonymous Coward]

NASA's gotten really serious about "protecting the heritage of the moon landing sites", 'cause, you know, they're not gonna get there again. That's why the last moon orbiter was crashed on the back side of the moon, for example, despite the difficulties and lack of scientific results that implied. Of course, it's little funny considering how many meteor impacts Moon has all the time, and they're not going to heed NASA's exclusion zones. I guess an impact on the back side is more likely both for them and random space junk though, as the Earth facing side is somewhat shielded by Earth.

Still it'd be nice to hear substantiation for the "danger of impacting the moon". Also ISEE-3 is still far from home safe, they've yet to even determine if there's any fuel left. The trajectory maestro who planned all its original trajectories himself estimated there will be about 50-50 chance of success for re-capturing it.

Re:Avoided moon impact as well

[Megane]

If this is true, I think a bigger danger might have been missing the moon, but slingshotting it into who knows what trajectory.

Cloud computing can byte me ...

[IwantToKeepAnon]

This is Oort cloud computing. :-p Seriously, funny how "cloud computing" sounds like nifty nomenclature when you're earthbound. But see if from a totally different perspective and it doesn't sound so nifty anymore. Not that this satellite is greater tech than we have now, but what if we were visited by an interstellar race; what would they think of our "cloud computing"?

And a nice non-sequitur: Orbiting this at a distance of roughly ninety-eight million miles is an utterly insignificant little blue-green planet whose ape-descended life forms are so amazingly primitive that they still think digital watches are a pretty neat idea.