Huygens Probe Prepares for Saturn Moon Landing 273
Nathan writes "A probe is about to land on one of Saturn's 35 moons, Titan. The probe is a collaboration with NASA, the European Space Agency and Italy's space program. The probe is apparently about the size of a Volkswagen Beetle. This landing should lead scientists toward new information about the atmosphere and the magnetosphere."
Good luck! (Score:2, Insightful)
Re:Good luck! (Score:5, Funny)
Wait...are you wishing them good luck in Metric or English measurements?
Re:Good luck! (Score:2, Informative)
Re:Good luck! (Score:2)
Shyeah. Try telling that to the men and women back at Mission Control.
Re:Good luck! (Score:3, Funny)
Shyeah. Try telling that to the men and women back at Mission Control.
He didn't say anything about women.
Probe size (Score:5, Funny)
An original Beetle, or a Super Beetle? Or even a new water-cooled "New Beetle"?
With the Italian involvement, wouldn't comparing it to a Volkswagen Scirocco be more appropriate?
at least the probe isn't being compared to a Ford Probe...
Re:Probe size (Score:3, Funny)
Re:Probe size (Score:2)
Re:Probe size (Score:2)
Re:Popular science cliche (Score:4, Funny)
Re:Popular science cliche (Score:2)
Re:Probe size (Score:5, Funny)
After NASA's previous troubles with imperial measurements, I'm glad to see that they're moving to standard pop-scientific units. The standard unit of volume is based on the Super Beetle, since that was the current model when this benchmark first came into widespread use.
BTW, the standard Beetle has recently been redefined in terms of human hair; it is now defined as exactly 1.374569443*10^14 cubic human hair widths. The length of a football field and the distance from New York to San Francisco have similarly been redefined as hair multiples. These recent harmonizations will help bring a new consistency to science news stories across all media outlets.
Re:Probe size (Score:2)
Wouldn't that be fun:
"These darn units keep shrinking"
Actually, my biggest pet peeve is using a number in the thousands or millions infront of a unit that has a kilo or mega.
"several thousand kilometers" instead of "several megameters"
if you are trying to dumb things down, why use a prefix on the unit at all? For example, "several million meters".
Re:Probe size (Score:2)
Seriously, these new units have me confused.
Re:Probe size (Score:3, Funny)
Re:Probe size (Score:2)
Well, if they'd compared it to another Ford product, the Pinto, then it'd burn up on impact with the planet and they wouldn't even have anything left to recall...
About the size of a Volkswagon Beetle? (Score:2)
Oh, and just for clarification, how many Libraries of Congress are there in a VW Beetle?
I can't wait (Score:2, Funny)
Timeline and (better) coverage... (Score:5, Informative)
It'd be worth staying up for, but the last time I did that, I jinxed the Mars Polar Lander.
If the Huygens timeline executes as planned, it will rank among the coolest engineering achievements in history. It will also have happened thanks to one guy who kept his eye on the ball [ieee.org] when nobody else was paying attention.
Re:Timeline and (better) coverage... (Score:2)
I almost feel like I should get up early for it, it being one of the few astronomical events we don't have to worry about cloud cover for. (If not for the four-year-old, we might. He's a proto-geek, but that'd be pushing it.)
Re:Timeline and (better) coverage... (Score:4, Informative)
"In short: Cassini is at Saturn, and about to launch the Huygens probe into Titan's atmosphere (splashdown 14th January 2005). The communication link between Huygens and Cassini was not thoroughly tested before launch. Some thoughtful engineer realised this might be a problem, and after some pushing against resistance, managed to test Cassini's response to how they expect the signal from Huygens to look. Surprise suprise, Houston we have a problem. Turns out, the original engineers took account of doppler shift in the carrier wave, but not in the encoded data. D'oh! Problem is encoded in firmware, can't be fixed after launch. Double d'oh! So instead, they've altered Cassini's trajectory to eliminate the doppler shift. Hurrah for Boris Smeds!"
http://gimbo.org.uk/archives/2005/01/boris_smeds_
Re:Timeline and (better) coverage... (Score:3, Interesting)
How totally exciting, to be here in the future
Re:Timeline and (better) coverage... (Score:3, Funny)
Your are guilty of temporal violation. Please remain where you are! Time police are making there way to you now. Don't try sneaking back to your own time either
More detailed timeline and overview (Score:2)
More coverage: NASA TV and Planetary Society blog (Score:3, Informative)
It also looks like NASA TV will have live coverage [nasa.gov] for much of Friday. You can access their video and audio streams here [nasa.gov].
Re:Timeline and (better) coverage... (Score:4, Informative)
It's a real shame that the private Italian subcontractor didn't allow transparency in the plans for the transmitter. I mean, this is a SCIENCE mission, not a competition for profits. (The company viewed NASA as their competitor, and the transmitter as proprietary).
The board discovered that Alenia Spazio SpA, the Rome-based company that built the radio link, had properly anticipated the need to make the receiver sensitive over a wide enough range of frequencies to detect Huygens's carrier signal even when Doppler shifted. But it had overlooked another subtle consequence: Doppler shift would affect not just the frequency of the carrier wave that the probe's vital observations would be transmitted on but also the digitally encoded signal itself. In effect, the shift would push the signal out of synch with the timing scheme used to recover data from the phase-modulated carrier.
Because of Doppler shift, the frequency at which bits would be arriving from Huygens would be significantly different from the nominal data rate of 8192 bits per second. As the radio wave from the lander was compressed by Doppler shift, the data rate would increase as the length of each bit was reduced.
Although the receiver's decoder could accommodate small shifts in the received data rate, it was completely out of its league here. The incoming signal was doomed to be chopped up into chunks that didn't correspond to the actual data being sent, and as a result the signal decoder would produce a stream of binary junk. The situation would be like trying to watch a scrambled TV channel--the TV's tuned in fine, but you still can't make out the picture.
Alenia Spazio wasn't alone in missing the impact Doppler shift would have on the decoder. All the design reviews of the communications link, including those conducted with NASA participation, also failed to notice the error that would threaten to turn Huygens's moment of glory into an embarrassing failure.
Alenia Spazio's insistence on confidentiality may have played a role in this oversight. NASA reviewers were never given the specs of the receiver. As JPL's Mitchell explained to Spectrum, "Alenia Spazio considered JPL to be a competitor and treated the radio design as proprietary data."
JPL's Horttor admitted that NASA probably could have insisted on seeing the design if it had agreed to sign standard nondisclosure agreements, but NASA didn't consider the effort worthwhile, automatically assuming Alenia Spazio would compensate for the changing data rate.
Re:Timeline and (better) coverage... (Score:2)
Something about that makes the hairs on the back of my neck stand on end. Goodness knows how he feels today!
Re:Timeline and (better) coverage... (Score:3, Informative)
I've got a copy of the ESA Bulletin journal from either January or February 1985 which was given to me years ago by a friend of the family - and one of the main articles is about the Huygens probe, in a form very similar to the final version launched in 1997. I think I ought to scan the article and post it online, just to give people an indication of how thoroughly planned these projects are. Unfort
Interesting article tidbits (Score:3, Funny)
I didn't know Italy had a space program, though I suppose it makes sense.
"It's really very cold." ... Temperatures hover around -292 F (-180 C) ...
And the understatement award of the year goes to...Candice Hansen, a scientist for the Cassini-Huygens mission!
Re:Interesting article tidbits (Score:2)
Your comment about the Italians reminded me of this old joke [jokesmagazine.com]
Re:Interesting article tidbits (Score:2)
A sight no one has ever seen before... (Score:2, Insightful)
Re:A sight no one has ever seen before... (Score:2)
Re:A sight no one has ever seen before... (Score:2)
I literally just spit vodka out of my nose.
Re:A sight no one has ever seen before... (Score:4, Interesting)
What I've thought was so cool about all of this is that they've taken IR pictures throgh the haze. They can see things, but they haven't a clue what they're looking at. Now that's cool!
I've seen Titan myself many times, but only as a tiny spark of light along for the ride with Saturn. I've seen 5 of the 35 moons through my backyard telescope.
I wish the ESA folks all the best.
...laura
Re:A sight no one has ever seen before... (Score:3, Interesting)
Re:A sight no one has ever seen before... (Score:4, Interesting)
I smell a spinoff TV movie and possible series... (Score:3, Funny)
called "Herbie the Love Probe." Wait...that doesn't sound right. It won't be a TV movie, it'll be the new hot pr0n on satellite. It'll certainly be easy to transmit!
I'm so going to hell now.
Here is a Countdown (Score:5, Informative)
In the application, you can also fastforward and see what Cassini does in the coming years.
Re:Here is a Countdown (Score:2, Funny)
Re:Here is a Countdown (Score:2)
For those interested in discussing this on irc (Score:5, Informative)
This channel is devoted to discussion of space science, current, past and future space missions.
This channel is frequented by a lot of knowledgeable folk. And please keep the discussion on topic
Y
Re:For those interested in discussing this on irc (Score:2)
Please stop by and check it out.
Y
Not just images... (Score:4, Interesting)
From SpaceflightNow [spaceflightnow.com]
"Also among the expected post-landing data are sounds from a microphone that might capture the rustling of frigid nitrogen winds or lapping waves."
Re:Not just images... (Score:2, Informative)
Alex's Ship (Score:2)
If you don't what I'm talking about, then you've probably never had the pleasure of watching the "Star Blazers" series... I used to run home from the school bus stop to watch it...
Andrew
A Star Blazers Reference! (Score:2)
But how did Alex manage to travel all the way to Iscandar without the help of FTL drive, or warp technology? It took the Star Force the better part of year to get there.
So many ads (Score:2)
IF it fails (Score:2)
Nobody would even know
The probe is a collaboration with NASA, the Europe (Score:2)
>> European Space Agency
Oh, boy, this will be a hard landing then. NASA shoulds send rovers to repair this thing after it "lands".
this just in from Titan... (Score:2, Funny)
Good luck (Score:2, Funny)
Fingers Crossed (Score:2)
Let's hope the probe's designers had lots of Landingvergnugen.
VLBI observations of Huygens' descent (Score:5, Interesting)
The data transmitted by Huygens will be uploaded to the Cassini spaceprobe and then transmitted by Cassini back to Earth several times. This data will be received by the NASA DSN dishes such as that a Tidbinbilla near Canberra in Australia.
Separate to this will be a unique experimental observation organised by JIVE, the Joint Institute for VLBI in Europe that will involve 17 radio telescopes around the world including the Parkes dish in NSW. They will monitor the weak signal of the Huygens probe directly to detct any doppler shift in the signal. Using VLBI (Very Long Baseline Interferometry) astronomers hope to be able to pinpoint the entry of Huygens into Titan's atmosphere to within 1 km. As it descends under parachute they also hope to use doppler shifts to measure the speed of the wind at different levels in the atmosphere. Should be an interesting observation.
(Disclaimer; I work for one of the institutes involved in this experiment)
Re:VLBI observations of Huygens' descent (Score:2)
Re:VLBI observations of Huygens' descent (Score:2)
Re:VLBI observations of Huygens' descent (Score:2)
That's AMAZING!
I did some googling and found these
www.esa.int (Score:5, Informative)
A 346 words article from India Daily is not the most relevant for an ESA project.
I hope
Huygens' carrier signal detected! (Score:4, Interesting)
This means that the probe survived the entry (heat-shield) phase of the descent and the main parachute opened, but we still have to wait for the main part of the show...
The probe is alive ! (Score:3, Interesting)
The Great Big Telescope (officially the Robert C. Byrd Green Bank Telescope) at Green Bank, West Virginia has detected [esa.int] the carrier signal from the Huygens probe.
This means that the spacecraft is alive, has made it through re-entry, and the parachute has deployed.
A total of 17 radio telescopes here on Earth are tracking [esa.int] the Huygens probe, using a technique called Very Long Baseline Interferometry, or VLBI [nasa.gov]. Using phase referenced VLBI, it should be possible to track the Huygens descent to within about a kilometer on Titan, and to get descent velocities to within a few millimeters / second along the line of site. This will give us a pretty good idea of the winds that the probe encounters as it descends, and also should really nail down the rotation of Titan if the probe makes it to the surface. Here [www.oan.es] is a more detailed description (pdf file) of what's being done using VLBI from Leonid Gurvits.
While this does not mean that the Huygens mission is a full success (I personally want pictures from the surface!), it does mean that some scientific data will be returned. I can't wait to see more.
Re:35 (Score:2)
Re:35 (Score:2)
Re:35 (Score:2)
Re:35 (Score:2, Funny)
Re:35 (Score:2)
Einstein makes it 5....
Re:35 moons! (Score:5, Insightful)
Mars has 2 captured asteroids as moons (most likely), whereas we have a gigantic almost-a-double-planet-system going. It's not surprising that Mars, one of the asteroid belt "border" planets would have such a moon (let a lone 2).
Re:35 moons! (Score:5, Insightful)
Ah, but the Earth is cooler than the other side of the pillow. Our moon is very large in comparison to the size of Earth. Viewed from afar, the Earth/Moon combination must appear to be more like a set of twin planets, instead of a planet/satellite combination. Saturns planets, while some may be large, appear to be very small in comparison to Saturn.
While none of us have experience in checking out other solar systems, I'll be willing to hypothesize that, in this galaxy, there are very few planet/satellite combinations that are very comparable in mass/size (as the Earth/Moon combo is).
Check back with me when we get to Alpha Centauri in 10,000 years.
Re:35 moons! (Score:4, Informative)
Like the Pluto/Chiron? [nasa.gov]. Closer ration than Earth/Moon. [nasa.gov]. So there is a closer ratio example in *our* system.
Hypothesis are suppose to educated guesses based on *current* knowledge. Thus, you are not hypothesizing, but just guessing.
Re:35 moons! (Score:2)
You know as well as everyone else that Pluto has always been represented as the 9th planet to school kids. Anyone now older than maybe 5, that is.
Re:35 moons! (Score:2)
Re:35 moons! (Score:3, Funny)
Pah! We'll be on future tech 47 by then and probably have a Conquest victory before you get your Space Race victory. Besides, the game ends in 45 years...
Re:35 moons! (Score:4, Funny)
Re:35 moons! (Score:2)
Saturn has a lot more than two rings. [nasa.gov]
Re:35 moons! (Score:2)
anyways.. they're sterilised.
and moreover.. if we restrained from checking anything out anywhere for this reason, we could just take a box and close it. then we could pretend that there's a whole ecosystem going on in there with the miracle of cold fusion.
Re:35 moons! (Score:2)
Re:In other news... (Score:2)
In other news, NASA has decided that the next Saturn probe will have a sticker that says "Saturn revolves around the earth". A judge in Georgia will be reviewing the inevitable lawsuit.
first probe images (Score:3, Funny)
Umm .... mars? (Score:5, Insightful)
Then there's the small matter of the mars rovers, which both worked beyond all possible expectations.
NASA have had their fair share of screw-ups, but I think if there's anything to take them to task about its their beaurocracy and the amount it costs them to do things, rather than their success rate. I'd like to see them able to lob off far more probes for less money, even if a few more failed, but that doesn't seem to be how they work.
Note that I'm no NASA fanboy, just trying to be a little realistic here.
Re:Umm .... mars? (Score:2)
Besides, Huygens isn't a NASA probe, it just hitched a ride there.
Not NASA. (Score:5, Informative)
And NASA's Mars rovers are still going strong, whereas the ESA's Beagle is just a crater.
Re:Not NASA. (Score:2)
But Not ESA Either (Score:5, Informative)
Re:Not NASA. (Score:2)
My old boss had a very high position at JPL and took me in for an extensive tour of the Cassini project. It was great asking the project manager all the questions I had. I was even able to go into the clean room and take a very close look at the satellite.
It's hard to believe that what I was looking at is now so far away...
Re:Titan (Score:2)
Re:Titan (Score:3, Insightful)
Re:Only a few hours until it makes a crater on Tit (Score:2)
And I agree that the Italian contractor fucked it up badly.
Re:Only a few hours until it makes a crater on Tit (Score:2)
Re:Only a few hours until it makes a crater on Tit (Score:2)
Re:Only a few hours until it makes a crater on Tit (Score:2)
Shit, don't tell the FCC; they'll fine the Deepspace Network.
Re:Only a few hours until it makes a crater on Tit (Score:2)
Re:Only a few hours until it makes a crater on Tit (Score:2)
Re:Only a few hours until it makes a crater on Tit (Score:4, Informative)
Furthermore: "Alenia Spazio (the Italian contractor) wasn't alone in missing the impact Doppler shift would have on the decoder. All the design reviews of the communications link, including those conducted with NASA participation, also failed to notice the error that would threaten to turn Huygens's moment of glory into an embarrassing failure."
Get your facts right (although being AC, no doubt it was just xenophobic bullshit on your part).
Re:Only a few hours until it makes a crater on Tit (Score:2, Informative)
http://www.spectrum.ieee.org/WEBONLY/publicfeat
hint: it was a Swede working at ESA in Germany... so much about team play
Re:Only a few hours until it makes a crater on Tit (Score:2)
"The [investigation] board discovered that Alenia Spazio SpA, the Rome-based company that built the radio link, had properly anticipated the need to make the receiver sensitive over a wide enough range of frequencies to detect Huygens's carrier signal even when Doppler shifted."
So far, so good.
Furthermore:
"Alenia Spazio wasn't alone in missing the impact Doppler shift would have on the decoder. All the design reviews of the communications link, including those conducte
Re:Why oh why (Score:2, Insightful)
Once it leaves the insulating vacuum of space and settles into the -300F atmosphere of Titan (almost as cold as liquid nitrogen), the probe is going to freeze solid in short order. It would probably be hard to include an RTG with enough juice to keep it warm on Titan without it overheating the probe on the 7-year trip.
Variable-heat RTGs (Score:2, Interesting)
Um, and then move them even closer together, really fast, if the probe is ever captured by hostile Martians and needs to self-destruct. ;-)
Or does the stuff in RTGs not decay faster when it gets neutrons sprayed at it?
Re:Why oh why (Score:2)
Re:Huygens NASA/ESA probe? (Score:2)
Re:Huygens NASA/ESA probe? (Score:2)
The only thing I could find on the NASA and ESA websites was that NASA built Cassini, ESA built Huygens, and the Italy provided the high-gain antenna.
Re:Timeline? (Score:2)