Slashdot Mirror
Ulysses Spacecraft on its Last Legs
doconnor writes "JPL announced that Ulysses' mission will be ending after 17 years. The power generated by the decay of a radioactive isotope has been slowly decreasing. To conserve power its main transmitter was shut off. Unfortunately due to a fault in its power supply it cannot be turned back on. The team plans to continue operating the spacecraft in its reduced capacity, using the alternate S-band transmitter, for as long as they can over the next few weeks." Congratulations to all the geniuses involved in this one.
First reply!
I'm not sure if the congratulatory statement was sarcastic or sincere, but I hope it was sincere. From the article:
"The joint NASA and European Space Agency Ulysses mission to study the sun and its influence on surrounding space is likely to cease operations in the next few months. The venerable spacecraft, which has lasted more than 17 years or almost four times its expected mission lifetime, is succumbing to the harsh environment of space."
Further on the article states that the lifetime was expected to be five years, so three times, not four, but still, a spacecraft tripling its expected useful life is a strong testament to the skill of its engineers.
cheers,
Andrew
Like you could build a spacecraft that lasted for 17 years. What have you done for humanity, Taco? Coded some Perl scripts?
...decay of a radioactive isotope has been slowly decreasing
isn't that what radioactive isotopes do?
If you go to the publications page for Ulysses, you'll see that about 60 PhDs have been awarded for Ulysses research, in addition to vast numbers of research papers and other article. By any count, this mission has been a success. Congratulations to all involved.
We all know what to do, but we don't know how to get re-elected once we have done it
Penelope's gonna be mad when you return to Ithaca. According to the prophecy, you should have returned from Troy seven years ago!
Don't look at me - I'm still p*ssed off that the Enterprise's original 5-year mission got cancelled after 3 years, you ignorant clod!
17 years ... I can just see it now. Imagine how fat Shatner would have been by the series end? Oh, we don't have to imagine ... but he'd still be getting all the green chicks ...
And Dr. McCoy could have actually said "I'm dead, Jim!"
I've been reading "People" magazine and USA Today and the main point they say is that we cannot build more nuclear plants because radioactivity lasts forever. So this 17 years thing is just baloney.
Probably another excuse so the US can shoot it down
[signature]
I'd like to hope that the "geniuses" comment featured in the article post, but I honestly can't tell. I think some of the previous posts point out, better than I can, how unseemly sarcasm would be in this case.
For information on how successful the Ulysses mission has actually been, including its recent historic third pass over the north solar pole, Please refer to the Ulysses home page at JPL:
http://ulysses.jpl.nasa.gov/
In any case, I'd like, perhaps, to suggest that the article post could either have been written, or otherwise reviewed, with more editorial skill. Then again, maybe that's asking too much. And that statement was not intended to be sarcastic.
Cheers,
--joe.
The mission of Ulysses was to use a Jupiter gravity assist to go out of the plane of the solar system, and
thus observe the Sun from high solar latitudes. It fulfilled that mission and lasted long enough to observe both
the North and South poles of the Sun. I would say it was fully successful.
It is not uncommon for the death of old spacecraft to be messy or even sloppy - the Viking 1 lander was killed by a programming bug -
but that does not detract from their earlier successes.
Your first mistake was in assuming that a slashdot editor would actually RTFA. On the other hand, it makes me feel better that the editors do the same thing I do when it comes to commenting on articles they haven't read.
Cheers,
Dave
They that can give up essential liberty to obtain a little temporary safety deserve neither safety nor liberty.
Ben
Since when do spacecraft have legs?? Or is this one of those things that would have been explained if I had RTFA, or even TFS for that matter...
I've got to say that I am blown away by this. Look at it in these terms: where I work, we are really proud of the fact that we've got a router that has an uptime of something like 2 1/2 years. It's in a data center in a very remote village in Alaska -- the only way in is via airplane. However, it is reachable, it's in a more or less climate-controlled environment and it has (relatively) stable power.
By contrast, Ulysses is traveling in one of the most hostile environments we can imagine. Everything in the shade is approaching -400F (IIRC) while everything on the side facing the sun is getting blasted with the full fury of solar radiation. There's no way to reach it for maintenance. It's technology is 17 years old now. It has no protection other than its own skin from any micro-meteors it encounters. And it has been running continuously since it was launched. You've gotta admit that's an impressive feat. Yeah, I'd say the NASA engineers responsible for Ulysses are 1) definitely geniuses, and 2) very deserving of congratulations.
MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?
It's amazing how long they last without the effects of gravity and an atmosphere with dust and oxygen etc.
Although maybe they're just rugged, the Mars rovers have lasted a long time on the surface of Mars.
Ulysses may have done a great job studying the sun, and may think it's hard work is over. But I suspect Ulysses is going to have a long and difficult 10-year journey home, for which it will eventually become better known than for its actual work it went out there for.
Watch out other NASA satellites (I'm looking at you, Cassini): I'd advise not making any moves on Penelope.
Can anyone tell me how to set my sig on Slashdot?
STS-41 Launch: ESA Ulysses Oct. 6, 1990
http://www.youtube.com/watch?v=bqmYWgivsHw
Thank you Ulysses!
Is it me, or is everyone's sarcasm meter broken and pointing in the wrong direction? On the plus side, the pessimism meter's working.
www.isoHunt.com
They turn that way after the kiss him.
This was a triumph.
I'm making a note here: HUGE SUCCESS!
It's hard to over state my satisfaction.
"It is our blasphemy which has made us great, and will sustain us, and which the gods secretly admire in us." - Zelazny
Their site is amazing! It shows all of the instruments and links to the data they've provided directly. For instance, the DUST instrument measures dust impact events (imagine that). You can use the heliocentric latitude and longitude for these thousands of events to track the spacecraft position throughout it's 17 year journey. A nice readme file explains the structure of the data file. That's just one of the 12 scientific instruments. Very cool stuff...
On another note, why are people saying four times as long as they expected? 17 years is closer to three times the original five years than four. You can't really say it's lasted four times as long as expected until after it has lasted 20 years.
For those that havn't seen pictures, Ulysses is one of the most beautiful spacecraft ever built. Some future archeologist will love getting this for their museum: http://upload.wikimedia.org/wikipedia/commons/6/68/Ulysses_spacecraft.jpg
Covered mostly in gold and other types of metals, the craft looks more like something out of a movie than a real craft.Here's to losing my Karma Bonus again....
This is truly an awesome feat! Ulysses represents what mankind can do when it puts aside its petty differences and works for the betterment of all.
Now, let's shoot it down before the Chinese do!
Switching the transmitter off was just NASA's way of telling Ulysses that the cake is a lie.
C'mon back to my place baby, I last longer than the Ulysses spacecraft...
In Soviet Russia, your work assignment is extended to 17 years.
Have gnu, will travel.
I for one suggest more target practice.
Badges!?! We don't need no stinking badges!
HIT It with a MISSLE!!
YeeeeHAW
"This kinda makes me wonder if NASA and other space agencies purposely over-estimate the useful lives of their spacecraft."
;-)
If they were purposefully overestimating the useful lives then the spacecraft would be running a shorter time than they said. They *may* be underestimating the times on purpose, but it is notoriously difficult to estimate the lifespan for something that can not (easily) be tested in the environment that it is going to be used in.
Any chance the some of the remaining fuel can be used to change the trajectory to go closer to the sun, perhaps extending the life a bit more?
Contribute to civilization: ari.aynrand.org/donate
Is it just me, or is it highly ironic that the Ulysses spacecraft (to study the sun) didn't use SOLAR power?
-Styopa
Ulysses is a great success, but let us look at its history a bit before we praise NASA.
http://en.wikipedia.org/wiki/Ulysses_(spacecraft)
Ulysses was originally part of the International Solar Polar Mission (ISPM) where two spacecraft were to pass over the North and South poles of the Sun simultaneously. In 1981, NASA backed out. There would only be one ISPM spacecraft. I was at the Jet Propulsion Lab then, and while the NASA scientists and engineers were disappointed, the Europeans were well and truly pissed. Simultaneous polar measurements are what was used to sell the mission to the governments.
ESA built the spacecraft (designed in the 70s), but the launch from the shuttle was delayed until 1990 by the Challenger disaster. A generation of European space scientists who expected to use the (now renamed) Ulysses data lost out.
Let us instead praise ESA and the European space scientists for this mission.
Wow. It obits the sun, but can't get enough power from solar panels. That's kinda sad, says something about the feasibility of solar power, for terrestrial budget applications, compared to JPL's application with no adverse weather to block the sun, and presumably, the very best, most efficient cells. Curious idea, one end of the probe in constant sunlight, the other end in constant cold of space, heat pump anyone?
Ulysses was important because it was the first spacecraft dedicated to studying the sun from it's poles, and indeed, at all latitudes. This may seem trivial, but conditions genuinely are different there than at the equator. As far as I know, Ulysses is the only spacecraft to have ever been launched into a polar orbit about the sun. As an added bonus, Ulysses has a gamma ray spectrometer that has been useful in helping scientists determine the approximate origin of distant gamma ray bursts. Direction finding of GRB's is almost impossible because they go straight through mirrors and dishes. Since it is out of plane with other similarly equipped spacecraft, it can help with 3-D triangulation of GRB's.
The mission extensions were a double bonus, because they allowed Ulysses to study the sun over a complete 11 year cycle.
Lest credit be missed, Ulysses was a joint mission between ESA and NASA.