What is really amazing is that the probe still operates after over 3 decades, which is a testament to the design team. It’s a SNAP to keep powered up though. – Anthony
Artist concept of Voyager near interstellar space. Image credit: NASA/JPL
From NASA JPL: (h/t to Dr. Leif Svalgaard)
PASADENA, Calif. – The 33-year odyssey of NASA’s Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind.
Now hurtling toward interstellar space some 17.4 billion kilometers (10.8 billion miles) from the sun, Voyager 1 has crossed into an area where the velocity of the hot ionized gas, or plasma, emanating directly outward from the sun has slowed to zero. Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars.
The event is a major milestone in Voyager 1’s passage through the heliosheath, the turbulent outer shell of the sun’s sphere of influence, and the spacecraft’s upcoming departure from our solar system.
“The solar wind has turned the corner,” said Ed Stone, Voyager project scientist based at the California Institute of Technology in Pasadena, Calif. “Voyager 1 is getting close to interstellar space.”
Our sun gives off a stream of charged particles that form a bubble known as the heliosphere around our solar system. The solar wind travels at supersonic speed until it crosses a shockwave called the termination shock. At this point, the solar wind dramatically slows down and heats up in the heliosheath.
Launched on Sept. 5, 1977, Voyager 1 crossed the termination shock in December 2004 into the heliosheath. Scientists have used data from Voyager 1’s Low-Energy Charged Particle Instrument to deduce the solar wind’s velocity. When the speed of the charged particles hitting the outward face of Voyager 1 matched the spacecraft’s speed, researchers knew that the net outward speed of the solar wind was zero. This occurred in June, when Voyager 1 was about 17 billion kilometers (10.6 billion miles) from the sun.
Because the velocities can fluctuate, scientists watched four more monthly readings before they were convinced the solar wind’s outward speed actually had slowed to zero. Analysis of the data shows the velocity of the solar wind has steadily slowed at a rate of about 20 kilometers per second each year (45,000 mph each year) since August 2007, when the solar wind was speeding outward at about 60 kilometers per second (130,000 mph). The outward speed has remained at zero since June.
The results were presented today at the American Geophysical Union meeting in San Francisco.
“When I realized that we were getting solid zeroes, I was amazed,” said Rob Decker, a Voyager Low-Energy Charged Particle Instrument co-investigator and senior staff scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “Here was Voyager, a spacecraft that has been a workhorse for 33 years, showing us something completely new again.”
Scientists believe Voyager 1 has not crossed the heliosheath into interstellar space. Crossing into interstellar space would mean a sudden drop in the density of hot particles and an increase in the density of cold particles. Scientists are putting the data into their models of the heliosphere’s structure and should be able to better estimate when Voyager 1 will reach interstellar space. Researchers currently estimate Voyager 1 will cross that frontier in about four years.
“In science, there is nothing like a reality check to shake things up, and Voyager 1 provided that with hard facts,” said Tom Krimigis, principal investigator on the Low-Energy Charged Particle Instrument, who is based at the Applied Physics Laboratory and the Academy of Athens, Greece. “Once again, we face the predicament of redoing our models.”
A sister spacecraft, Voyager 2, was launched in Aug. 20, 1977 and has reached a position 14.2 billion kilometers (8.8 billion miles) from the sun. Both spacecraft have been traveling along different trajectories and at different speeds. Voyager 1 is traveling faster, at a speed of about 17 kilometers per second (38,000 mph), compared to Voyager 2’s velocity of 15 kilometers per second (35,000 mph). In the next few years, scientists expect Voyager 2 to encounter the same kind of phenomenon as Voyager 1.
The Voyagers were built by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., which continues to operate both spacecraft. For more information about the Voyager spacecraft, visit: http://www.nasa.gov/voyager . JPL is a division of the California Institute of Technology in Pasadena.
Astounding. Well on its way to meeting Captain Kirk.
“In science, there is nothing like a reality check to shake things up, and Voyager 1 provided that with hard facts,” said Tom Krimigis, principal investigator on the Low-Energy Charged Particle Instrument, who is based at the Applied Physics Laboratory and the Academy of Athens, Greece. “Once again, we face the predicament of redoing our models.”
Except in climate science, which is settled. (<———– sarcasm)
That’s how science should be done! Now if only climate “scientists” would do the same.
What happens to Voyager I when it passes into interstellar space… i.e. – will it then sail along caught in the interstellar wind?
We’ve only a few years to await the answer. Cool.
NASA Space is worth every last penny.
“Once again, we face the predicament of redoing our models.”
OMG !!
I am a little disappointed they cancelled the other 4 Voyagers. 😉
Amazing! Any idea of how long we’ll be able to keep up communications, and the time lag involved?
Amazing.
I have followed this crafts journey for all of its life, I watched the launch and have seen other craft launch and after many years go quiet, but Voyager has been different.
I never thought it would still be able to communicate so much for so long. I once heard a speaker that said the power of the sattelite times the area of the reciver was a constant value, and I have seen over the years that as Voyager got quieter our ears grew bigger and bigger and are now the largest global array of co-ordiated listening devices. Seeking out the flickering signal of a 50 watt light 10 billion miles away. Unbelieveable.
They have and continue to do the impossible. We, and all of science, owe them all a debt of gratitude for both their insight and their craftsmenship. Thank you all.
NASA used to do good science – cutting edge science. What happened?
The outward speed has remained at zero since June.
This is a big clue to something else. ‘The outward speed has remained at zero’ i.e. is not positive or negative but zero. Since no particle can have zero velocity in all direction, obviously it must be perpendicular, so no an outward component. These solar wind particles would be pulled back by Sun’s gravitation, not along the heliospheric sheet, but at the higher latitudes, forming a return current of protons, closing the loop, creating possibility of a feedback!
1977, a good year for design, engineering, planning and execution to have come together to launch such an astounding human achievement.
Voyager 1 must be one of the most incredible accomplishments of our species.
33 years later and BILLIONS of miles away and it is still working.
Stunning.
They don’t make ’em like they used to, eh?
Here’s to many more years and more discoveries out of the Voyagers.
Andrew30 says:
December 14, 2010 at 2:01 pm
Amazing.
I have followed this crafts journey for all of its life, I watched the launch and have seen other craft launch and after many years go quiet, but Voyager has been different.
…
They have and continue to do the impossible. We, and all of science, owe them all a debt of gratitude for both their insight and their craftsmenship. Thank you all.
======================================================
Like you I have followed Voyager I & II since their inception.
Sadly, working in Avionics for the last 20 odd years means that I understand that the levels of achievement considered normal for the Voyager era are a forgotten thing. Now “management” dictate the level of achievement considered affordable whilst trying to pretend that the level of engineering & testing is as good as it always was…
If you’ve never come across it, I’d suggest “Skunk Works” as a good (but saddening) read for those working in the industry these days…
It has been 33 years in earth time, but how long has it been travelling in Voyager 1 time?
I’m confused, a not unusual circumstance where this blog is concerned. From the article,
That says to me the wind velocity is zero relative to the Voyager’s speed, but not zero, say relative to the sun. If relative velocity is zero, then actual (relative to the solar system?) is whatever speed Voyager is moving. Have I missed some key to the story?
cheers,
gary
Unbelievably COOL!
“Now hurtling toward interstellar space some 17.4 billion kilometers (10.8 billion miles) from the sun,”
If I’ve done the maths right, this is 1/2357th of the way to Alpha Centauri, our nearest star, making it another 70,,000 years before Voyager would arrive there were it heading in the right direction.
I hope this gives some sense of the sheer vastness of outer space…..
V1 has actually traveled farther than the distance shown. Total mile traveled since launch is 13,896,000,000
Check the info at the bottom of this page:
http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm
That means it has traveled about .86 of a light day in 33 years. At that rate it would take about 60,000 years to reach the next nearest star. Pretty big place out there.
What’s all the fuss about. Here is another vehicle launched about the same time and – you can own it:
http://dixie-dream-cars.ebizautos.com/detail-1977-cadillac-eldorado-cabriolet-used-1176793.html
Has fewer miles too!
It makes me proud. Gives me one of those warm fuzzy feelings, proud of what we (mankind) has managed at times to accomplish. Can you imagine the pride of the folks who were directly involved in the design and manufacture, and in dealing with any technical problems that may have been encountered along the way?
Talk about awe inspiring in so many different ways. May Voyager continue to have a very very long life, sending us all sorts of nifty tidbits!
I am sure i saw Blue Peter do an arcticle on this in their studio on what Voyager was going to do and what it was also taking with it about our planet, the ‘Golden Record’.. Goodness me that makes me feel old… !!
When are NASA going to make time capsules??
They realized that our trust, which they had earned, could be used to fund ever more ambitious things, and ultimately be used to direct policy at the highest level of government.
In other words they have abused our trust and no longer deserve it.
gary turner says:
December 14, 2010 at 2:40 pm
When the particles hitting the ship are hitting at exactly the same speed as the ship is moving, then the particles are (at least in the direction of travel) not moving.
The key is they are not at zero velocity relative to the ship, but at zero velocity relative to the Sun.
And every year they have to fight for the couple of million dollars to keep funding the analysis of data. My wife works on the Voyager 2 data and it is year to year as to if she will have a job.
My dad was involved with these missions, back when NASA meant science. Three of the missions I work never made it. One blew up (with the Challenger 🙁 ), one just disappeared, and one made a big crater. At least some of the stuff I worked on has made it 20 years. Boy I hate socialists. They destroy everything they touch in the name of ideology.
Now, NASAs latest chief scientist is a AWG propagandist, Waleed “The Ice is Melting” Abdalati.
http://www.nasa.gov/topics/people/features/abdalati.html
Providing a foundation for propaganda is so much more important then providing a foundation for science. We can kiss space good bye.
There’s even a song:
If you like that you might like the rest of “Minus Ten and Counting” also.
Just search for it on YouTube.
NASA space scientist: “The data does not match our models. Our models must be wrong.”
NASA climate scientist: “The data does not match our models. The data must be wrong.”
These people work for the same “company?”
Mark
yamaka
December 14, 2010 at 2:24 pm
###
I also witnessed the destruction of a culture of excellence from the inside. I do believe the destruction was deliberate, having lived through the democratic parties GAO witch hunts of the late 80s. They literally set this country back a decade on technology and tripled the cost of doing anything.
This “Work with Business to get to Space” thing they are now advertising, is just a scam. SpaceX is a crony capitalist venture that is in bed with the current administration. I mean, everything NASA has ever built was built by businesses.
Sorry if I sound bitter, but I am.
“Once again, we face the predicament of redoing our models.”
I have yet to hear such an honest statement from a climate modeler.
Doug in Seattle says:
December 14, 2010 at 3:00 pm
“They realized that our trust, which they had earned, could be used to fund ever more ambitious things,[…]”
Like not measuring the temperature in Bolivia. Doesn’t sound THAT ambitious to me…
V-ger is indeed a great accomplishment . I remember all the planet-stops. Inspiring.
All the “vastness” talk is defeatism.
It took a mere 100 years to go from coal fed railroads to Voyager.
If we kept at it “vastness” would just be a matter of patience, eventually.
Of course, our current administration really doesn’t believe in manned spaceflight.
So very soon Astronauts will be hitting the unemployment line, while Asimo takes their jobs.
“They took our jobs “!
If my math is right, the radio delay would be about 16.1222646012 hours, based on their 14.4 Billion Km distance or about .67 light days.
So somewhere between .67 and .86 light days.
Now if we develop warp drive in another 33 years we will be able to run it down in less than 2 days travel at light speed 😉
Larry
There is a reason why NASA doesn’t do Voyager level exploration now but you are not meant to know about it . If you will stop believing everything you read in the press and hear on TV you can begin to find out what is really going on.
Americas’ finest engineers and scientists did not become stupid all of a sudden in 1985. Somebody is driving this wreck and they mean to run it in the ground.
To get some perspective on just how amazing this is consider the state of consumer electronics in 1977 compared to today. There aren’t even a lot of cars from 1977 that still function unless they have been completely refurbished. What was cutting edge in 1977? A really good cartridge on your turntable? A cassette deck? Maybe a digital watch or a calculator? Little CB radios with 4 watts of output on the 11 meter band were about the best mobile communications that average citizen could hope for. Even much more sophisticated 2m VHF rigs for hams were crude by today’s standards. The average home didn’t have a computer. Virtually no one had a cell phone.
Now consider that against this backdrop NASA engineers designed and built a space craft that is STILL sending useful information back to Earth 33 years later. I have an electric shoe polisher from 1968 that still functions amazingly well. Other than that I don’t possess a single item that takes batteries or plugs into the wall that is 33 years old.
He wrotes:
What is really amazing is that the probe still operates after over 3 decades, which is a testament to the design team
Well of course it is still operating, it’s not running on fossils fuel. Electric power with radioactive generator.
vukcevic,
generally, space plasmas are neutral in charge, so there is no electrical current. However, the sheath may separate the charges, with electrons heading North and ions heading South – or whichever. Interesting thought though.
Dave Bowman: Hello, HAL. Do you read me, HAL?
HAL: Affirmative, Dave. I read you.
Dave Bowman: Open the pod bay doors, HAL.
HAL: I’m sorry, Dave. I’m afraid I can’t do that.
Dave Bowman: What’s the problem?
HAL: I think you know what the problem is just as well as I do.
Dave Bowman: What are you talking about, HAL?
HAL: This mission is too important for me to allow you to jeopardize it.
Dave Bowman: I don’t know what you’re talking about, HAL.
HAL: I know that you and Frank were planning to disconnect me, and I’m afraid that’s something I cannot allow to happen.
Dave Bowman: Where the hell’d you get that idea, HAL?
HAL: Dave, although you took very thorough precautions in the pod against my hearing you, I could see your lips move.
Dave Bowman: Alright, HAL. I’ll go in through the emergency airlock.
HAL: Without your space helmet, Dave, you’re going to find that rather difficult.
Dave Bowman: HAL, I won’t argue with you anymore. Open the doors.
HAL: Dave, this conversation can serve no purpose anymore. Goodbye.
Gary D. says:
December 14, 2010 at 2:39 pm
It has been 33 years in earth time, but how long has it been travelling in Voyager 1 time?
=============================================================
Arf, Arf, 231??
33 years and keeps on ticking. Pretty impressive.
swt
Still.. the dent and ribbon, haven’t given up all their secrets yet.
10Au difference in the Voyagers distance is still intriguing for me.
That would be quite alot of turbulence or two different interstellar flow directions striking the heliospheric nose, type location or.. I’m tired zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
This kind of thing inspired me to become an engineer. Unfortunately I arrived fresh out of school at a prime contractor working under NASA to discover that what I wanted to do was over with before I was born….sad. Oh well, life moves on, still inspired by what was done way back when before all the *change*. I jumped ship and haven’t looked back. A wise move in retrospect.
Those of you on the outside looking in have no idea how dysfunctional the place is. JPL does some neat things, but the rot flows from the top down. I no longer support NASA. I think the space science should be farmed out to various universities, with grants to continue the actual science missions. Climate data….I’ll listen to the people the commodities traders pay…..
As far as the analogies to the progress made in the previous first half of the last century, the theoretical framework was there for the physics at least a century ago. We are up against a brick wall there right now. Poo-Poo the vastness of space at your peril. It’s a big cold universe out there and it makes Antarctica look like palm beach.
I sure hope there is somebody working on the flux capacitor warp drive in their garage. Something that will cause the Physicists to re-write their models, but short of that…the rocket equation is a b&*%ch. Nothing in my life has ever been as disappointing as that realization. Other than the fact that if there is that person out there and they succeed….they will be sent to the gulag for crimes against the planet if discovered. Oh, and I’m stuck here with the dead-enders.
Just returning from AGU, hence this late repsonse.
vukcevic says:
December 14, 2010 at 2:03 pm
These solar wind particles would be pulled back by Sun’s gravitation, not along the heliospheric sheet, but at the higher latitudes, forming a return current of protons, closing the loop, creating possibility of a feedback!
Robert of Ottawa says:
December 14, 2010 at 5:07 pm
generally, space plasmas are neutral in charge, so there is no electrical current. However, the sheath may separate the charges, with electrons heading North and ions heading South – or whichever.
As Robert says there is no electric return current. Sadly, the press release is completely screwed up. Voyager 1 is now just matching the solar wind speed, which means that they both travel outwards at 17 km/sec [for the moment]. The solar particles left the Sun with a speed higher than the escape velocity and will therefore never return to the Sun [and surely not ‘at higher latitudes’ – what makes them go up there?]. When the solar wind hits the Earth’s magnetic field it is also deflected around the Earth. And the wind is still moving outwards at 17 km/sec, so has not slowed to zero. NASA gets an F for this nonsense.
” Poo-Poo the vastness of space at your peril.”
While completely respecting your opinion, and even more, your facts, I would say I don’t poo-poo it, I sort of embrace it.
Shouldn’t there be something between chemical rockets and flux-capacitor warp drives ?
Fascinating.
Obviously the New York office of GISS had nothing to do with the data interpretation.
Also, having been built in the 70’s, the Voyagers had no parts built in China, hence they last.
Further, politicians aren’t demanding a particular outcome from the Voyager venture.
All the above leads me to believe this story rather than not.
p.s. Can an amateur intercept the Voyager signals or just NASA? Just asking.
John F. Hultquist says: (December 14, 2010 at 2:50 pm) What’s all the fuss about. Here is another vehicle launched about the same time and – you can own it:
But the steering wheel’s on the wrong side, John…
Leif Svalgaard says:
“Voyager 1 is now just matching the solar wind speed, which means that they both travel outwards at 17 km/sec”
This was under the interpretation that the speed was relative to the space craft. Actually, the solar wind speed monitor failed back in 1980, and Voyager 1 cannot measure the solar wind speed directly. It is, however, possible to estimate the speed from the distribution of low-energy particles hitting the spacecraft. The abstract [I didn’t hear the talk – too much going on] reads:
AN: SH23D-02
TI: Low-energy Charged Particles at Voyagers 1 and 2 10-20 AU into the Heliosheath (Invited)
AU: *Decker, R B
EM: robert.decker@jhuapl.edu
AF: Space, Johns Hopkins Univ. Applied Physcis Lab., Laurel, MD, USA
AB: Voyager 1 (115 AU, N34°) and Voyager 2 (93 AU, S29°) have been in the heliosheath since Dec. 2004 and Sep. 2007, respectively. Intensities of low-energy ions 40 keV – few MeV observed at Voyager 1 have been relatively steady since mid-2006. The heliosheath-averaged (5.6-year) Voyager 1 energy spectrum rolls over slightly with increasing energy, with the spectral index changing from -1.5 to -1.7. Intensities of ions 30 keV – few MeV observed at Voyager 2 have been relatively steady since about 2009.4, in contrast to the large quasi-recurrent variations observed from 2007.66 (termination shock) to 2009.4. The low-energy ion energy spectrum at Voyager 2 is slightly harder than that at Voyager 1. The Voyager 2 spectrum averaged over 2007.66-2009.4 shows a rollover, with the spectral index changing from -1.3 to -1.5. After about 2009.4 at Voyager 2, the lower energy ion channels show large anisotropies consistent with the observed direction of heliosheath plasma flow, but not with its speed. Preliminary analysis suggests that in addition to H+, these channels may also be measuring heavy ions, i.e., pickup He+ and/or O+ at energies gt 4 and gt keV/nuc, respectively, that could be boosted into sunward viewing sectors of the detector by the ~150 km/s heliosheath flow. Intensities of energetic (0.02-1.5 MeV) heliosheath electrons began decreasing exponentially at Voyager 2 on 2009.15, and are now at detection background. Energetic electron intensities at Voyager 1 remain high. We estimate the heliosheath plasma flow velocity in the R-T (instrument scan) plane at Voyager 1 by using angular data from the three lowest energy ion channels that cover 40-139 keV. We cannot measure the component of flow normal to the R-T plane. During 2007.7-2010.5, the estimated radial component of flow decreased from ~60 km/s to ~0 km/s at a rate of -20 km/s/yr. On average, the tangential component of flow has been at about -40 km/s from termination shock crossing onward, but continues to show broad variations of ±20 km/s.
This would mean that the spacecraft is now ploughing into the wind at 17 km/s. So, the interpretation of a sideways deflection seems to be reasonable. If so, the solar wind has been slowed by interaction with the interstellar medium, and is no longer just coasting outward. The particles cannot return to the Sun as they will be picked up by the outflow if they moved closer. The solar wind keeps both its own debris and interstellar ions at bay.
Amazing! Any idea of how long we’ll be able to keep up communications, and the time lag involved?
Both Voyagers have enough electrical power and thruster fuel to last until around 2020. Current communication time is about 13 hours one way.
It’s my understanding that they have to disable instruments along the way to compensate for declining electrical output and only a few instruments are still operational. The radio will be the last to power off.
Monty ,
The good people who can do this sort of stuff aren’t at NASA anymore. Their modern equivalents are working at SpaceX working on Falcons and Dragons, as shown by their OUTSTANDING performance last week.
Mind-blowing!
Chris
Norfolk, VA, USA
Gary D. says:
December 14, 2010 at 2:39 pm
It has been 33 years in earth time, but how long has it been travelling in Voyager 1 time?
Someone check my math, I am a bit rusty, but if Voyager had been travelling at its current speed of 17 km/sec for all 33 years, it would have experienced a time dilation of about .016 seconds. In reality it was travelling faster earlier in its life, but still, I would not expect it to have accumulated more than perhaps .03 seconds total.
Got to go REAL fast before relativity makes much difference.
Fantastic! Thanks for posting this.
It’s just like so far out there man……
Seriously, this is one of the greatest successes of science; and also a strong endorsement of nuclear power.
I think it’s cool that the Voyagers are still reporting back. However, I don’t get the same sense of awe as others do as to how far it’s gone. Sure, it’s amazing and all. To me, it’s more how humans tend to give up when faced with insurmountable challenges. Yet, we look at the vastness of space and it has the exact opposite effect. We see possibilities. Humanity will never give up its quest to reach the stars. Voyager (quite appropriately named) is more about the first steps in that long journey, as was the case with going to the moon. It is humanity taking those steps whether physically or not. In the future, when we look back, the Moon mission and Voyager will always be in the history books and a reminder to future generations of our determination. I think we need that reminder today more than ever.
My part of these vehicles was as chief engineer of the large Stage I solid rocket motors which gave them their first motion from the pad at the Cape. So many miles and so many years lay ahead of them and it’s not over yet. It sort of boggles the mind to reflect that we have more computing power in our iPhones than was available to us in the design and launch of these V’gers.
I can’t wait for the Klingons to lay a tractor beam on one of these and bring it on board. They will marvel at the gold LP record with a message from Nixon giving greetings from Earth and deciding that wiping out the blue planet wouldn’t be worth the effort after all. I hope the next time we take on a mission like this (fat chance) we can do as well as the guys at JPL did with the Voyager payload.
/Reminiscence. Back to work.
@ Mike Borgelt
Regarding Space X, I completely agree. I have followed them with great interest. A well run company, but they are still up against physics and biology. You gotta start somewhere though. I’m in the stands cheering them on. Wish I was on the team….timing is everything.
@ Jimash:
>Shouldn’t there be something between chemical rockets and flux-capacitor warp drives ?
If you find it, let me know.
Regg_upnorth says:
December 14, 2010 at 5:04 pm
Well of course it is still operating, it’s not running on fossils fuel. Electric power with radioactive generator.
This is hardly the point. The electronics 33 years ago were not hardened like they are today. For the Voyager’s to be still communicating is a matter of excellent design. You could have all the power of the universe, but if the electronics are degraded to the point of failure, there is nothing to show for it. Solar/cosmic radiation is an electronics killer. Now that it is on edge where cosmic radiation is even more damaging, if the Voyager’s continue to communicate, even more the amazement.
1977, same year Star Wars came out. I was 15. Went and saw it 13 times at the theater.
Looking for that unique gift for that special person? I highly recommend:
Voyager: Seeking Newer Worlds in the Third Great Age of Discovery, by historian Stephen J. Pyne (Viking Press 2010)
available at Amazon and your best book stores. Those seeking a space adventure and nothing more will be surprised and possibly confused by this book because it is so much more than that. The story of Voyager, from early conception to launch to the gravity assist past the outer planets to the heliosheath is in there, but so is an exploration of exploration itself, the history and motivations for societal investment in seeking new worlds, whether they are distant planets, deep sea rift zones, or new continents. All graced by Pyne’s remarkable and delightful gift for prose.
A soundbite that should be looped into a song for climate science-fiction artists:
“Once again, we face the predicament of redoing our models.”
“Once again, we face the predicament of redoing our models.”
“Once again, we face the predicament of redoing our models.”
…
I acknowledge that it is hard work, but sometimes pay needs to be earned.
Leif Svalgaard says:
December 14, 2010 at 7:07 pm
This would mean that the spacecraft is now ploughing into the wind at 17 km/s. So, the interpretation of a sideways deflection seems to be reasonable. If so, the solar wind has been slowed by interaction with the interstellar medium, and is no longer just coasting outward. The particles cannot return to the Sun as they will be picked up by the outflow if they moved closer. The solar wind keeps both its own debris and interstellar ions at bay.
Hi Leif. Would voyager know if the local particle density was increasing? I ask because logically, if the particles from the solar wind stop moving outwards, and they can’t go inwards as you insist the solar wind will blow them out again, then they must surely accumulate at the boundary with the heliosheath.
Leif Svalgaard says:
December 14, 2010 at 7:07 pm
So, the interpretation of a sideways deflection seems to be reasonable. If so, the solar wind has been slowed by interaction with the interstellar medium, and is no longer just coasting outward. The solar wind keeps both its own debris and interstellar ions at bay.
Sideway deflection or perpendicular, same thing.
There is no escape for charge particles.
What then?
The particles cannot return to the Sun as they will be picked up by the outflow if they moved closer.
This must be wrong.
1. Electrons combine with the incoming galactic ions, creating ENAs as observed by IBEX
http://science.nasa.gov/media/medialibrary/2010/01/14/15jan_ibex2_resources/model.jpg
2. Protons are either accumulating there for billions of years, creating permanent ever increasing proton cloud ? , not likely, nothing like that has been found or observed. No electronic device would survive such radiation and the Voyager would be doomed.
I suggest, protons slow down, turn around along inner boundary of heliosphere and head ‘home’, outside the helio-sheet
http://solar-heliospheric.engin.umich.edu/images/CurrentSheet2%5B1%5D.jpg
pulled back by the sun’s gravitation, eventually spiralling into the sun’s at the high latitudes.
Monty says:
December 14, 2010 at 8:53 pm
@ Jimash:
“>Shouldn’t there be something between chemical rockets and flux-capacitor warp drives ?
If you find it, let me know.”
I’ am not sure what a flux-capacitor warp drive is or does. But as for a true space drive I am working on it. pg
This is one of those ‘WOW!’ moments filled with the awe and wonder that good educators try to provide kids with from time to time.
Thanks for this, Anthony.
Dr. L.S
The solar particles left the Sun with a speed higher than the escape velocity and will therefore never return to the Sun [and surely not ‘at higher latitudes’ – what makes them go up there?.
Escape velocity from the sun (a year earlier) is nothing to do with it if protons eventually slow down.
What makes them go up there?.
Simple physics. On many occasions you quoted garden sprinkler as an analogy of solar wind.
To elaborate further: I suggest use your garden hose and point jet of water (solar wind) at the garden wall (heliosheath) and see the analogous effect. Water droplets do not come back into the water jet (helispheric current sheet –heliosheet ), they disperse around 360 degrees.
Now position an industrial air extractor next to your hose (to simulate the sun’s gravity pull). Outgoing jet of water is hardly affected, but what about water droplets bouncing of the wall? I suggest if any caught by the jet will be swept back (and hit the wall again), those outside the jet (heliosheet) will get pulled in by the extractor (sun’s gravity).
As simple as that.
Some time soon we may have a compression problem similar to the sound barrier for aircraft. The solar wind banking up against the cosmic particles could produce a severe boundary layer that is not conducive to electronics the sparks may fly. I am hoping it has no trouble and gives us a small insight into free space devoid of the suns influence..
What we learn maybe profound in its message to science.
vukcevic says:
December 15, 2010 at 1:48 am
Re: Escape velocity from the sun (a year earlier) is nothing to do with it if protons eventually slow down.
Should not be in italics; my comment and not Dr.S’s quote.
[Easy fix employed ….. bl57~mod]
Re Anything is possible says:
Depressing thoughts for an SF fan. Impressive performance from Voyager though and an inspirational achievement. Latest data also makes musing about solar sail performance more interesting. Aint science great?
As for popping over to Alpha Centauri, we need more power! Which also opens up fun what if scenarios. Gen 1 colony ship leaves to build new home in Alpha Centauri, arrives and finds Gen 5 colony ship got their first. Assuming there’s something there to colonise, and assuming it could be habitable or made habitable. And assuming we could model it’s climate. We struggle with our ‘simple’ solar system, that one has 2 or possibly 3 suns to factor into climate models :p
vukcevic says:
December 15, 2010 at 1:48 am
Dr. L.S
what makes them go up there?.
Simple physics. On many occasions you quoted garden sprinkler as an analogy of solar wind.
It ain’t bad in the day
If they squirt it your way
‘Cept in the winter when it’s froze
An’ it’s hard when it hits on your nose
-Frank Zappa: Uncle Remus-
tallbloke says:
December 15, 2010 at 12:52 am
then they must surely accumulate at the boundary with the heliosheath.
And they do [in a fashion]. The result is called the ‘Hydrogen Wall’ which also contain interstellar ions. The whole shebang eventually slides off to the side and merges with the galactic medium.
vukcevic says:
December 15, 2010 at 1:11 am
Electrons combine with the incoming galactic ions, creating ENAs
The ENAs move so fast that gravity is negligible.
pulled back by the sun’s gravitation, eventually spiralling into the sun’s at the high latitudes.
Why at high latitudes? There is also a solar wind at high latitudes. Those particles should then go sideways and spiral in at low latitudes.
Anyway, the solar wind does not come back but goes sideways [the sideway speed is large enough to keep the particles from falling in, just like the sideways speed of the Earth prevents it from falling]. The solar wind plasma eventually mixes with the interstellar galactic plasma at distances of 1000 AU.
simple physics
Einstein: “make it as simple as possible, but no simpler”.
There is still some very cool science out there in space, everything from Hubble to Swift digging deep into the past and giving us images and data of our universe no one could have imagined in 1977. Unfortunately space travel beyond Mars, for humans, is running into very serious roadblocks, not the last of which is our own short time in this universe and our inablilty to rapidly aclimate ourselves to weightlessness over extended periods. However, getting something like Voyager, only much smaller, packed with the latest technology, close to the speed of light should be a top research priority. Think about how much space you would need for somthing with the computing power of a smart phone in 1977. We should beable to scale down for sattelites as well and set up launch sites outside of earth’s gravity.
vukcevic says:
December 14, 2010 at 2:03 pm
Funny what you say…..they will be “surprised” by the outcome..
What goes up must come down
spinning wheel got to go round
Talking about your troubles it’s a crying sin
Ride a painted pony
Let the spinning wheel spin (Blood, Sweat & Tears lyrics).
I understand that the EPA has determined that V’ger 1 and 2 are contaminating the Universe and that they must both be retrieved and dismantled by 31 Dec 2012. The cost will be absolutely mindblowing and the United States will cease to exist, but the environment is the environment and, regardless, the regulations that the law authorizes the current EPA Administrator to dream up must be obeyed. (Oh yes! Sarc Half Off. There’s always a grain of truth in every ‘joke’.)
Robert of Ottawa says:
December 14, 2010 at 5:07 pm
vukcevic,
generally, space plasmas are neutral in charge, so there is no electrical current.
THERE IS NOTHING NEUTRAL IN THE UNIVERSE. Entiende?. We’ll be neutral….the moment we die. We have been wrongly taught , for example, that a glass ash tray (to put the ashes of cigarettes -another forbidden issue-)it is a dielectric and so we “believe” it is neutral and, worse!, “solid”…however when making glass vials for injections these must be “neutral”(i.e. having a very low reactivity with the liquid which will be contained in it).
Πάντα ῥεῖ καὶ οὐδὲν μένει
Everything flows, nothing stands still
Heraclitus of Ephesus (c.535 BC – 475 BC)
And in order to move ahead, you gotto have one foot ahead of your other foot, and the angle between your legs (or between the “legs” of a triangle) it is called, by electrical engineers, the “phase angle”, which, in the case of alternate current it is 90 degrees. But this angle can vary, as it is the sum of sin y+cos y.
Everything in the universe “walks” or “flows” and this is done by vectors moving their legs as we do.
This is why, also, women walk behind men, in the Japanese culture 🙂
This is real science – unlike CAGW. The wheels have come off that bandwagon, and it’s no fun bashing it any more, everybody is a denier. It’s the weather wot dunnit, innit?
How about this – why has Voyager 1 not experienced the anomalous decceleration experienced by Pioneer 10, apparently defying our understanding of gravity? Completely O/T here, but anyone know of an appropriate blog?
You’re not alone there. However, we are part of a dying breed. NASA stopped inspiring, so there are fewer young people who even believe it’s possible to push into the final frontier in an meaningful way. I imagine I am one of the last who was so inspired, though it wasn’t so much by NASA as by a NASA rebel who wrote a very good book on becoming a space-faring society and why we should be doing it.
I disagree with this. I would say that humanity is against the same wall that the developed world in Europe was against when it looked at the Atlantic Ocean 500 years ago. There’s nothing in space that can’t be overcome. We may not ever achieve faster-than-light travel, but that’s no reason why humanity can’t move beyond this star. Even if it takes multi-generational spacecraft of asteroid-sized mass travelling at tiny fractions of c, it can be done, and if humanity can survive long enough without killing each other or falling victim to a solar-system disaster, it will be done. In fact, it’s likely we’re in better shape than the explorers in Spain were up against, at least we can see what’s out there before we get there. Those men on those wooden ships had no such comfort and some likely believed they were on a suicide mission.
Jeremy says:
December 15, 2010 at 7:59 am
There’s nothing in space that can’t be overcome.
What can’t be overcome is right here back on Earth…
Human pettiness, stupidity, and science illiteracy.
Dr. S thanks for the reply.
ENAs are of no consequence since they do not have a charge.
High latitudes (if coming back) charged particle would be guided by magnetic field (kind of to ‘aurora’ effect)
Sideway explanation sounds plausible except for:
Analysis of the data shows the velocity of the solar wind has steadily slowed at a rate of about 20 kilometers per second each year…
August 2007, when the solar wind was speeding outward at about 60 kilometers per second….
Initial speed is say 400km/s, down to 60km/s , i.e. down to 15% of the initial; there is definite de-acceleration. There is nothing around to pump more energy into SW, so de-acceleration would continue, regardless of direction, forward, sideways or backward. Eventually speed has to fall below the escape velocity, when gravity and solar ‘magnetic filled lines’ would come into play.
Would the solar wind had slowed to zero at that distance if it were active instead of spotless?
******
Monty says:
December 14, 2010 at 8:53 pm
@ Jimash:
>Shouldn’t there be something between chemical rockets and flux-capacitor warp drives ?
If you find it, let me know.
******
The next logical step would be nuke-powered drives. Some kind of magnetohydrodynamic-type ion-drive using helium or hydrogen heated/ionized by a reactor? Even if it produced only a fraction of a gee, the constant acceleration over yrs would produce an impressive velocity.
Or construct a giant nozzle attached behind a ship & explode 1000-megaton nukes in the nozzle inlet. OK, you’d somehow have to survive thousands of gees of acceleration. A giant shock-absorber/spring connected between the nozzle and the living quarters?
Monty: That’s Project Orion.
But although the Logos is common, most people live as if they had their own private understanding.
Heraclitus of Ephesus
In interstellar space there is only miniscule gravity and no ‘medium’ resistance. Once craft is far away from the sun a powerful light source (fusion reactor placed in the focus of a parabolic mirror in the back of the craft; reactor could be ignited at suitable point along trajectory) should in principle quickly accelerate craft to velocity that can’t be matched by any other propulsion system (remember solar windmill toy). 20% speed of light should be achievable. NASA how about it, I have filed provisional patent application, ready to negotiate?
Wow ! 7 planets of the Proxima Centauri in 20 years (grow plants and raise chickens on the craft for food, just filing another PPA for that too) .
A government which completely prioritises financial values over the technical ability of their engineers to develop ,will cause stagnation. In the UK in the 1960’s our aerospace industry which built Concorde, the Harrier. Handley Page Victor was sacrificed for financial expediency. If the TSR2 had been built it would still be a cutting edge aircraft.
The NASA which produced Apollo and the Voyagers was simply the best.
Maybe it will take a space race with India or China for the accountants to lose power and the engineers given the opportunityto deliver the product.
But at least the Voyagers give something to aspire to.
A peer-reviewed paper, Physical Review Letters, “Contribution of Strong Discontinuities to the Power Spectrum of the Solar Wind” (2010), by Joseph Borovsky of Los Alamos National Laboratory states that the conventional model of the solar wind could be wrong.
Rather than being a homogeneous body of plasma, the solar wind could be cellular in structure made up of magnetic flux tubes:
From the Los Alamos press release: “Borovosky argues that the discontinuities are part of a structure to the solar wind that looks like spaghetti, with the discontinuities being the boundaries between adjacent noodles (magnetic tubes). In this concept, the wind plasma is structured rather than being homogeneous. He suggests that the spaghetti structure of the solar-wind plasma reflects the “magnetic carpet” on the surface of the Sun, with the spaghetti in the wind being loose strands of the magnetic carpet.”
http://www.lanl.gov/news/releases/understanding_of_solar_wind_structure_might_be_wrong_newsrelease.html
Much more investigation needs to be done to confirm or falsify the above conclusion.
But, if it turns out to be valid and the solar wind is, indeed, made up of “magnetic tubes”, it needs to be further investigated to determine how far out into interplanetary space these “magnetic tubes” travel away from the Sun.
Indeed, the question then arises, do these solar wind “magnetic tubes” travel all the way out to the heliosheath?
From the story in the post:
“Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars…”
“The solar wind has turned the corner,” said Ed Stone, Voyager project scientist based at the California Institute of Technology in Pasadena, Calif. “Voyager 1 is getting close to interstellar space.”
The Voyager spacecraft does not have the capability to observe & measure whether the solar wind, charged particles, plasma, has a structure of “magnetic tubes”. But if the solar wind does have a structure of “magnetic tubes” at this distance from the Sun near the heliosheath, it suggests the possibility, that there is a “current” and is not simply “debris”.
And, as Vukcevic stated: “These solar wind particles would be pulled back by Sun’s gravitation, not along the heliospheric sheet, but at the higher latitudes, forming a return current of protons, closing the loop, creating possibility of a feedback!”
Now, I don’t know about the gravitation angle, but if there is a “return current of protons [and possibly electrons, too]”, could this “return” current of charged particles pick up energy from the heliosheath region and then funnel energy back to the Sun?
Of course, it’s only a hypothesis, but since the reported observations & measurements have surprised scientists, might there be other surprises in store?
Only if we are willing to accept the surprises!
And, are willing to incorporate these “surprises” into our ideas — perhaps, even coming up with new ideas about solar system dynamics.
Again, from the story in the post:
“When I realized that we were getting solid zeroes, I was amazed,” said Rob Decker, a Voyager Low-Energy Charged Particle Instrument co-investigator and senior staff scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “Here was Voyager, a spacecraft that has been a workhorse for 33 years, showing us something completely new again.”
Science is about observation & measurement and, when appropriate, discarding old ideas and replacing the old ideas with new ideas that are consistent with new observations & measurements.
“There’s nothing in space that can’t be overcome.
What can’t be overcome is right here back on Earth…
Human pettiness, stupidity, and science illiteracy.”
– Guess God has set us an agenda to overcome the internal obstacles first before conquering Space. Makes sense actually – No point it taking it out with us to outer space and contaminating it as well. Also if we are to harness much greater forces than nuclear, it is just prudent that we also possess the maturity and restraint to use it wisely.
Jeremy says:{December 15, 2010 at 7:59 am}
“Even if it takes multi-generational spacecraft of asteroid-sized mass travelling at tiny fractions of c, it can be done, and if humanity can survive long enough without killing each other or falling victim to a solar-system disaster, it will be done. ”
The problem with multi-generational spacecraft theory is not whether it can be done but whether the reason to do so would survive through the generations. Imagine how horrible it would be for the generations that will live and die during the travel to know that their generation was one of many deemed to be expendable so that some future generation would be able to reach a goal that was established generations prior to them being born. Methinks they would rebel and change the mission to better suit themselves and their children. Eventually it will become a matter of do they want to continue rather than can they continue.
Leif Svalgaard says:
December 15, 2010 at 4:49 am
tallbloke says:
December 15, 2010 at 12:52 am
then they must surely accumulate at the boundary with the heliosheath.
And they do [in a fashion]. The result is called the ‘Hydrogen Wall’ which also contain interstellar ions. The whole shebang eventually slides off to the side and merges with the galactic medium.
Thanks Leif. So it sounds a little bit analogous to the way the Earth’s magnetosphere wards off the incoming solar wind, and deflects it round the outside. Maybe the heliosphere leaves a trail of plasma balls behind it like the Earth does, creating reconnection shocks which reverberate back into the solar system?
Sarc Ozy says:
December 15, 2010 at 10:05 am
……………
I think this Sarc Ozy bloke is a very clever guy. Looked at his website, lots of fun.
Tom in freakin cold Florida says:
December 15, 2010 at 12:18 pm
…Eventually it will become a matter of do they want to continue rather than can they continue.
How is there any rational alternative to continuing with the mission if your delta-V has already changed sufficiently to make it impossible to stop, turn-around, and head back?
Vijay says:
December 15, 2010 at 11:57 am
“There’s nothing in space that can’t be overcome.
What can’t be overcome is right here back on Earth…
Human pettiness, stupidity, and science illiteracy.”
Those last characteristics will be contrary to survival in the space environment.
Even with chemical rockets a low earth orbit/Luna/Mars civilization has travel times no worse than when empires were held together by sailing ships.
hotrod (Larry L) says:
December 14, 2010 at 4:21 pm
Djozar says:
December 14, 2010 at 1:58 pm
“Amazing! Any idea of how long we’ll be able to keep up communications, and the time lag involved?
If my math is right, the radio delay would be about 16.1222646012 hours, based on their 14.4 Billion Km distance or about .67 light days.
So somewhere between .67 and .86 light days.
Now if we develop warp drive in another 33 years we will be able to run it down in less than 2 days travel at light speed ;)”
I assume you are talking about the time lag for TWO way communication as I get half that for ONE way communication not including the miniscule time dilation effects. No idea how long it can keep sending and receiving though. In English units 10.8 Billion miles divided by 386,000 mps.=7.77hours
I worked on the telemetry software for Voyager back in 1975-76 at JPL. I asked the question one day at a meeting with some of the scientists: “When will one of the probes reach another star?” The answer I got back was, “About 250,000 years it will get close to one.” (They told me which one, but I don’t remember what it was.)
Jeremy says:
December 15, 2010 at 12:55 pm
“How is there any rational alternative to continuing with the mission if your delta-V has already changed sufficiently to make it impossible to stop, turn-around, and head back?”
Who said anything about turning around and heading back? I just said they would change the mission to suit themselves and not worry about someone else’s dreams from generations past.
Minor points re the forgoing: I always thought that the nearest star (besides Sol) to Earth was Proxima Centuri, not Alpha Centuri. It would seem that Proxima is now considered part of a three-star Alpha system:
http://hypertextbook.com/facts/KathrynTam.shtml
but it is still listed as closer.
There have been numerous SF stories and novels written about multiple-generation starships sent out from Earth to colonize deep space. Many concern possible social pathologies of such small, self-contained worlds, notably Heinlein’s Orphans of the Sky, wherein the inhabitants have completely forgotten the purpose of the mission, and do not even understand that they are on a spaceship:
http://en.wikipedia.org/wiki/Orphans_of_the_Sky
Lastly, I am enormously impressed that we have engineers and scientists here who actually worked on or were associated with the Voyager program. It is a testament to the quality of this blog and our tireless host.
/Mr Lynn
Erratum: For ‘Centuri’ read ‘Centauri’. Proofread, darn it! /Mr L
Some of you got it wrong with regards to the speed of the solar wind.
They measured a solar wind speed of zero relative to the sun itself.
Suppose you are in a car going 100 Mph on the road. Suppose there is no wind today so the air doesn’t move. People inside the car will measure a wind speed of 100 Mph (exactly the speed of the car) wich means that the wind speed is effectivly zero.
Jim G,
That would be 186,000 miles/s, not 386,000 miles/s, for a little more than twice that time.
Mark
Tom in freakin cold Florida said: (December 15, 2010 at 12:18 pm) Imagine how horrible it would be for the generations that will live and die during the travel to know that their generation was one of many deemed to be expendable so that some future generation would be able to reach a goal that was established generations prior to them being born.
It would be horrible for us, Tom, but I feel it would not be horrible for those who were born to it. I doubt any of my grandchildren will ever long for the freedom of the family farm which was so important to me. It does not even seem important to my children, not born there and not really moved by my nostalgia. Life aboard a spacecraft, if that was all one had ever known, would be as sweet to them as the endless paddocks (fields, meadows) were to me — although it was not long before the bus trip into High School that I began to want the city (Paree?).
I really doubt they would feel “expendable” but more likely that this was just life. For the original parents it would be extremely difficult, as it would be in a different way to those who were alive when the destination was reached — but for those who’s lifetimes were bounded by the walls of the ship I would expect as much content and discontent as we Earthlings experience right now.
As to the flux capacitor warp drive…that was tongue in cheek, please try to read between the lines.
@ Mike, yes my heart wants us to go there, but I feel we are not ready. As Leif pointed out, we have many unresolved problems here…, Carl Sagan came to the same conclusion in the end. As to your early world empire analogies, I feel we are still at the skin boat level, paddling around in a back bay somewhere. We haven’t even developed the lateen sail yet. Clipper ships or at least long boats are needed, and many of those early colonies failed….
I am familiar with project Orion etc. Unfortunately politically and economically infeasible. Remember that colonies were to make money. The oceans are right here and we have only barely begun to utilize them. Space is much farther and much more daunting than the ocean. I build things for a living and therefore you must excuse my pragmatism.
The frontier for this century is biology…IF we can keep the dead enders in a check.
I seem to have confused Jeremy and Mike B in my last post. Also should read dead enders in check…although in a check seems to be the current strategy.
My apologies.
Leif Svalgaard says:
December 14, 2010 at 7:07 pm
..at Voyager 2 have been relatively steady since about 2009.4, in contrast to the large quasi-recurrent variations observed from 2007.66 (termination shock) to 2009.4. The low-energy ion energy spectrum at Voyager 2 is slightly harder than that at Voyager 1. The Voyager 2 spectrum averaged over 2007.66-2009.4 shows a rollover, with the spectral index changing from -1.3 to -1.5. After about 2009.4 at Voyager 2, the lower energy ion channels show large anisotropies consistent with the observed direction of heliosheath plasma flow, but not with its speed.
~
Thanks Leif..Hope AGU was some fun for you and that you learned something new. (lol)
Anyway, period of time for the above stats was during some of the lowest solar winds speeds, fields etc. of the space age. The heliosphere was still in shrinking mode. Frisch is suggesting that the shrinking is due to pressure changes of the VLISM. (very local interstellar medium) . If in I remember correctly .. one interstellar flow from Oph. and one interstellar flow from sco. cen. But none the less two interstellar flows are seen in the nearby VLISM. One of these flows faster and producing more pressure. I believe one of those flows was 28 km/sec. And since there is a hemispheric huge dent in the southern solar heliosphere, my thoughts are maybe this is the reason for that.
Vuks, they say that the flow of interstellar He is 26 km/s through the heliosphere. Was doing some scouting on the “He gravitational focusing cone.” Jupiter in its orbit hits the cone including the most dense portion of the cone on the backside of the sun.
Thanks Carla.
Would appreciate the link, if you got one.
You are, of course, right. That’s what happens when you do things from memory in old age. Had my units mixed and was thinking about the 3×10 to the 8th M/s and put that 3 in there instead of the 1 for the 186,000 miles per second. Have not figured out how to type exponentials on this computer so went with the English units. Mea Culpa, Mea Culpa, Mea Maxima Culpa.
@Puckster
‘The electronics 33 years ago were not hardened like they are today.’
I scrapped all your other text because the above bugs me. Are you absolutely positively insane!
Why do you think everything has gotten bloody cheaper? Back in the day they created stuff to last, because it was friggin expensive. Over the years, as is only proper, evolution, however, get to things to be much “thinner” because it saves money not because it makes stuff more “hardened” or last longer. What bone head company would want their stuff to last, today? Do you know that what made the network cards manufacturer go with life time warranty was such a simple thing as not wanting to reveal their design to nosy geeks trying to fix damaged, but otherwise very expansive, cards, and that is also why computer manufacturers in the 90’s already tried the sealed thin client approach. Hardware frakking suck today compared to how they were built before building to warranty length to save money became an issue for the buyer.
It is the same almost everywhere from building cars to houses, you don’t design nor build neither to last a hundred years today unless you can afford it or are very very special or some such, and space industry, today, can’t afford it, mostly because too few governments want to spend too big money on it.
Carla says:
December 16, 2010 at 5:30 am
I believe one of those flows was 28 km/sec.
It is the Sun that moves through the interstellar medium at ~26 km/s. When I drove to the AGU this morning, I drove through the fog at 50 mph. The fog does not move much.
vukcevic says:
December 16, 2010 at 1:02 pm
Thanks Carla.
Would appreciate the link, if you got one.
~
Two different articles Vuks, not sure which one you were referring.
I do think that it is interesting that the interstellar He neutrals flow through at 26 km/sec. One hand is saying, that sounds right and the other hand is making funny faces at me.
“”INTERSTELLAR NEUTRAL ATOMS AT 1 AU OBSERVED BY THE IMAGE/LENA IMAGER””
S. A. Fuselier1, A. G. Ghielmetti1, and P. Wurz2
published 2009 May 27
1. INTRODUCTION
..””Interstellar neutral helium has been observed in the inner
solar system directly (Witte et al. 2004) and through indirect
means, i.e., by pickup ion measurements (M¨obius et al. 1985;
Gloeckler & Geiss 1998) and EUV measurements (Vallerga
et al. 2004). The properties of these neutrals are reasonably
well understood. They appear as a relatively compact (∼few
degrees wide) source arriving from λ = 74. ◦ 5, β = −5. ◦ 5 (i.e.,
very near the apex direction) with a speed of approximately
26 km s−1 (14.5 eV), a temperature of ∼6300 K, and a density
of 1.5 × 10−2 cm−3 (M¨obius et al. 2004). These parameters
represent the unperturbed flow of neutrals into the heliosphere.
Interstellar neutral hydrogen with nearly the same speed (i.e.,
with an energy of a few eV) has been inferred from a variety of
measurements (e.g., Lallement et al. 1996; Gloeckler & Geiss
1998).”’
Or did you mean the Fritsch team on VLISM and CHISM and Flows and what not? Too many articles in the fire right now Vuks. Be back..
Leif Svalgaard says:
December 16, 2010 at 2:50 pm
Carla says:
December 16, 2010 at 5:30 am
I believe one of those flows was 28 km/sec.
It is the Sun that moves through the interstellar medium at ~26 km/s. When I drove to the AGU this morning, I drove through the fog at 50 mph. The fog does not move much
The Frisch team is suggesting that 2 km/sec difference would create a substantial differnce in the pressure gradient. Thats a 10 AU dent out there Doc.
So you couldn’t push the fog around, bummer driving like that.
Carla says:
December 16, 2010 at 5:51 pm
The Frisch team is suggesting that 2 km/sec difference would create a substantial differnce in the pressure gradient.
I don’t think they really mean that. Show us.
Leif Svalgaard says:
December 16, 2010 at 6:55 pm
Carla says:
December 16, 2010 at 5:51 pm
The Frisch team is suggesting that 2 km/sec difference would create a substantial differnce in the pressure gradient.
I don’t think they really mean that. Show us.
~
Well .. in context yes they did mean that.
And the article went on with the math comps on how they arrived at that conclusion. There has been several articles, as of late, from the Frisch team suggesting that the interstellar region is shaping the bubble and not the solar cycle. Maybe the solar cycle is the response to those interstellar changes . NO No can’t say that now.
I can show us, when my badly in need of a defrag brain finds it. lol That two different flow directions possibility would have been of some import, so should have that on paper. hmm
Vuks the relationship to the sudden stratospheric warming, the the polar vortex shear? May be related to the earth’s orbit out from the focusing cone. The description of the event is located in the last link. The event being, exiting the focusing cone. The exit not being the same as the entry. The time period and description is a bit more than coincidental.
Hypothesis: A perpendicular magnetic field to the pathway of the charged particles is deflecting those charged particles sideways.
Initially I was confused by the claims of the solar wind being zero, until I realized what confused me. The article says:
When the speed of the charged particles hitting the outward face of Voyager 1 matched the spacecraft’s speed, researchers knew that the net outward speed of the solar wind was zero
Note that this means the particles hitting the front or “outward facing” side of Voyager. It’s the side of the vehicle which is pointing away from the sun. So if the vehicle is moving at MPH relative to the sun, and Voyager tells us that particles are hitting its “windshield” at the same MPH, then it must be that those particles are not moving relative to the sun.