Voyager Enters Final Frontier Of Solar System |
Voyager Enters Final Frontier Of Solar System |
Guest_Sunspot_* |
Jun 3 2005, 10:47 PM
Post
#1
|
Guests |
http://planetary.org/news/2005/voyager-upd...ation_0524.html
Voyager 1, the most distant human-made object in space, has crossed the termination shock, the last major threshold in the solar system, team members announced today at the annual American Geophysical Union (AGU) meeting in New Orleans, Louisiana. |
|
|
Guest_spaceffm_* |
Jun 4 2005, 01:45 AM
Post
#2
|
Guests |
Do You think it is possible to see a picture towards the sun wikthout magnifictaion?
Is Voyager still this functionial? |
|
|
Jun 4 2005, 05:51 AM
Post
#3
|
|
Founder Group: Chairman Posts: 14432 Joined: 8-February 04 Member No.: 1 |
|
|
|
Jun 4 2005, 08:35 AM
Post
#4
|
|
Senior Member Group: Members Posts: 1870 Joined: 20-February 05 Member No.: 174 |
The instruments on the scan platforms have been turned off. The last camera use was the look back across the solar system that caught the "pale blue dot". The ultraviolet spectrometer was in use as a poor-man's ultraviolet astronomy spectroscopy satellite for some years, but was finally retired. Heaters on the instruments and scan platform gear-boxes are off so they've all cooled to various near-cryogenic temperature levels, far outside their design survivability ranges. Thermal contraction of materials has probably broken solder joints and the like.
The voyagers probably have not enough power to run anything on the scan platforms now, anyway, even if they weren't probably broken by the cooldown. |
|
|
Guest_PhilCo126_* |
Nov 13 2005, 05:48 PM
Post
#5
|
Guests |
I thought it would last untill 2015 before the first VOYAGER spacecraft will be in interstellar space ...
|
|
|
Nov 14 2005, 03:52 PM
Post
#6
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
QUOTE (PhilCo126 @ Nov 13 2005, 12:48 PM) I thought it would last untill 2015 before the first VOYAGER spacecraft will be in interstellar space ... I went to the official NASA/JPL Web site on the Voyagers and found this: http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm And if you go to the home Voyager page, they have links to the latest science data from the probes from this year. Go here and look on the left column under Latest Browse Data: http://voyager.jpl.nasa.gov/ This page has a rundown of what the Voyagers will be doing through the year 2020, when it is thought they will finally be unable to power even a single instrument: http://voyager.jpl.nasa.gov/spacecraft/spacecraftlife.html -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Nov 14 2005, 07:08 PM
Post
#7
|
|
Member Group: Members Posts: 624 Joined: 10-August 05 Member No.: 460 |
QUOTE (ljk4-1 @ Nov 14 2005, 08:52 AM) I went to the official NASA/JPL Web site on the Voyagers and found this... I pulled up some of data, the increase in cosmic ray count is an eye opener, at least doubling, if not more over the last two years. I am also intregued by the the fact that the plutonium powered system is producing more energy than expected. Over the short term, this can be written off as better-than-expected aging of the thermalcouples; but the trend looks like it is gnawing away at three sigma limits. Wouldn't it be a hoot if radioactive half-lifes turn out to vary as a function of AU? Could the increase in cosmic rays be effecting the decay rate? |
|
|
Nov 14 2005, 08:23 PM
Post
#8
|
|
Member Group: Members Posts: 356 Joined: 12-March 05 Member No.: 190 |
3-Sigma limits of what? Has anyone ever even studied thermoelectric junction degradation rate fluctuations over a period of 30 years?
|
|
|
Nov 14 2005, 08:41 PM
Post
#9
|
|
Member Group: Members Posts: 350 Joined: 20-June 04 From: Portland, Oregon, U.S.A. Member No.: 86 |
I wouldn't complain if the increase in cosmic rays (or something else out there) was somehow recharging the power supply (employ a more scientific-sounding explanation if you like)..
|
|
|
Jan 11 2006, 10:32 PM
Post
#10
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm
Voyager Mission Operations Status Report # 2005-11-11, Week Ending November 11, 2005 Command Transmission & Verification Operations Voyager 1 command operations consisted of the uplink of a command loss timer reset on 11/08 [DOY 312/1625z]. The spacecraft received the command. There were no Voyager 2 command operations due to the extended downtime of DSS-43. Sequence Generation Operations Continue sequence development of CCSL B131. Data Return Operations Voyager 1 Data Processing and Operations: There were 83.2 hours of DSN scheduled support for Voyager 1 of which 28.1 hours were large aperture coverage. There was one schedule change made on 11/09 [DOY 313] when 3.5 hours of DSS-65 support was released to support MUSC. The total actual support for the period was 79.7 hours of which 28.1 hours were large aperture coverage. There were no significant outages during the period Science instrument performance was nominal for all activities during this period. One frame of GS-4 data was recorded this week. A second frame of GS-4 data was recorded on day 309. The EDR backlog is 9 days. Voyager 2 Data Processing and Operations: There were 54.5 hours of DSN scheduled support for Voyager 2 of which 0 hours were large aperture coverage. There was one schedule change made on 11/09 [DOY 313] when 2.5 hours of DSS-45 support was released to support MUSC. The total actual support for the period was 52.0 hours of which 0 hours were large aperture coverage. There was one significant outage of 0.7 hours on 11/08 [DOY 312] due to a sub-reflector problem at DSS-45 [DR C104604]. Science instrument performance was nominal for all activities during this period. One frame of GS-4 data was recorded this week. The EDR backlog is 8 days. Flight System Performance Voyager 1 performance was nominal during this report period. Activities included a PMPCAL and switching to Band Low Power on 11/9 (DOY 313/314). Voyager 2 performance was nominal during this report period. PROPELLANT/POWER CONSUMABLES STATUS AS OF THIS REPORT Spacecraft Consumption One Week (Gm) Propellant Remaining (Kg) Output (Watts) Margin (Watts) 1 50.34* 28.58 292.9 35 2 7.87 30.49 294.5 41 *MAGROL 05-308/21:45 RANGE, VELOCITY AND ROUND TRIP LIGHT TIME AS OF 11/11/2005 Voyager 1 Voyager 2 Distance from the Sun (Km) 14,558,000,000 11,671,000,000 Distance from the Sun (Mi) 9,046,000,000 7,252,000,000 Distance from the Earth (Km) 14,669,000,000 11,736,000,000 Distance from the Earth (Mi) 9,115,000,000 7,292,000,000 Total Distance Traveled Since Launch (Km) 17,312,000,000 16,308,000,000 Total Distance Traveled Since Launch (Mi) 10,757,000,000 10,134,000,000 Velocity Relative to Sun (Km/sec) 17.162 15.610 Velocity Relative to Sun (Mi/hr) 38,390 34,919 Velocity Relative to Earth (Km/sec) 40.552 41.500 Velocity Relative to Earth (Mi/hr) 90,711 92,832 Round Trip Light Time (hh:mm:ss) 27:10:20 21:44:54 -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Jan 12 2006, 01:12 PM
Post
#11
|
|
Member Group: Members Posts: 509 Joined: 2-July 05 From: Calgary, Alberta Member No.: 426 |
QUOTE (ljk4-1 @ Jan 11 2006, 04:32 PM) Distance from the Sun (Mi) 9,046,000,000 7,252,000,000 Looks like Voyager 1 will pass 100 AU pretty soon. Not a scientifically important point, but significant in its own way. |
|
|
Feb 15 2006, 03:30 PM
Post
#12
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Voyager Mission Status 11/18/2005 and 11/25/2005:
http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm Feature video in the main Voyager page: http://voyager.jpl.nasa.gov/index.html 'Voyager enters the Heliosheath' by the Voyager Project Scientist, Dr. Ed Stone. -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Feb 22 2006, 05:12 PM
Post
#13
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
COSMIC RAY MYSTERY SOLVED
------------------------- When Voyager 1 finally crossed the "termination shock" at the edge of interstellar space in December 2004, space physicists anticipated the long-sought discovery of the source of anomalous cosmic rays. These cosmic rays, among the most energetic particle radiation in the solar system, are thought to be produced at the termination shock - the boundary at the edge of the solar system where the million-mile-per-hour solar wind abruptly slows. A mystery unfolded instead when Voyager data showed 20 years of predictions to be wrong. ... The paper, "An Explanation of the Voyager Paradox: Particle Acceleration at a Blunt Termination Shock," is available in the February 17 issue of the Geophysical Research Letters. http://spaceflightnow.com/news/n0602/19voyager/ -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Mar 14 2006, 04:00 PM
Post
#14
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Astrophysics, abstract
astro-ph/0603318 From: Merav Opher [view email] Date: Mon, 13 Mar 2006 19:30:59 GMT (539kb) Effects of a Local Interstellar Magnetic Field on Voyager 1 and 2 Observations Authors: Merav Opher, Edward C. Stone, Paulett C. Liewer Comments: 12 pages, 5 figures Journal-ref: Astrophysical Journal Letters v.640, 71, 2006 We show that that an interstellar magnetic field can produce a north/south asymmetry in solar wind termination shock. Using Voyager 1 and 2 measurements, we suggest that the angle $\alpha$ between the interstellar wind velocity and magnetic field is $30^{\circ} < \alpha < 60^{\circ}$. The distortion of the shock is such that termination shock particles could stream outward along the spiral interplanetary magnetic field connecting Voyager 1 to the shock when the spacecraft was within $\sim 2~AU$ of the shock. The shock distortion is larger in the southern hemisphere, and Voyager 2 could be connected to the shock when it is within $\sim 5~AU$ of the shock, but with particles from the shock streaming inward along the field. Tighter constraints on the interstellar magnetic field should be possible when Voyager 2 crosses the shock in the next several years. http://fr.arxiv.org/abs/astro-ph/0603318 -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Mar 16 2006, 11:32 PM
Post
#15
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
From updated solar wind speed diagram, Voyager-2 experienced a repentine increase (more than 100 Km/s) at the end of February/beginning of March.
In my understanding, transition through termination shock should produce a dramatic wind speed decrease, so this is not the case... Anyway still intriguing, because even if in the past Voyager-2 already observed speed close to 500 Km/s, now increase seems more repentine and appear associated to one of the largest ions density spikes ever observed by the spacecraft... Any suggestion? -------------------- I always think before posting! - Marco -
|
|
|
Mar 25 2006, 03:13 AM
Post
#16
|
|
Junior Member Group: Members Posts: 40 Joined: 20-March 06 Member No.: 720 |
From updated solar wind speed diagram, Voyager-2 experienced a repentine increase (more than 100 Km/s) at the end of February/beginning of March. In my understanding, transition through termination shock should produce a dramatic wind speed decrease, so this is not the case... Anyway still intriguing, because even if in the past Voyager-2 already observed speed close to 500 Km/s, now increase seems more repentine and appear associated to one of the largest ions density spikes ever observed by the spacecraft... Any suggestion? How bright is the light of the sun at the place where the pioneers and the voyagers are at (this) moment? Or is it completely dark there now ,please can you tell me that? Thanks. |
|
|
Mar 25 2006, 06:40 PM
Post
#17
|
|
Member Group: Members Posts: 509 Joined: 2-July 05 From: Calgary, Alberta Member No.: 426 |
How bright is the light of the sun at the place where the pioneers and the voyagers are at (this) moment? Or is it completely dark there now ,please can you tell me that? Thanks. Well, the apparent brightness of the Sun varies as the inverse square of your distance from the Sun. Right now Voyager 1 is about a hundred times farther from the Sun than we are. So that means that, as seen from Voyager 1, the Sun is about one ten-thousandth as bright as what we are used to. That's still about 500 times brighter than a full Moon, though. So although the Sun would look like a star from Voyager 1, it would be a really, really bright star. |
|
|
May 15 2006, 09:35 PM
Post
#18
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Something is definitely happening around Voyager-2!
Last nucleon data shows that, after 10 months of caothic behavior, density dropped to very low levels; in the meantime, wind speed stopped the regular descent (after the step-up previously noticed) and started to go up and down on a hourly scale (density and velocity seems to have a complementary behaviour...). I do not recall what exactly happened to Voyager-1 density data (any help?), but I strongly suspect termination shock is very close... or already passed! -------------------- I always think before posting! - Marco -
|
|
|
May 15 2006, 09:47 PM
Post
#19
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Based on Solar System Simulator, Voyager-2 is only 79.6AU from Sun: considering also the unfavorable heading direction, is too early for a termination shock encounter (but not impossible, it depends also from solar activity!).
Meanwhile, it is interesting to highlight that Voyager-1 is now only 130million Km from the 100 AU milestone! Should happens at mid August... I have to prepare some champagle bottle -------------------- I always think before posting! - Marco -
|
|
|
May 15 2006, 09:53 PM
Post
#20
|
|
Senior Member Group: Members Posts: 2488 Joined: 17-April 05 From: Glasgow, Scotland, UK Member No.: 239 |
Well, the apparent brightness of the Sun varies as the inverse square of your distance from the Sun. Right now Voyager 1 is about a hundred times farther from the Sun than we are. So that means that, as seen from Voyager 1, the Sun is about one ten-thousandth as bright as what we are used to. That's still about 500 times brighter than a full Moon, though. So although the Sun would look like a star from Voyager 1, it would be a really, really bright star. Rob: Any idea how far from the Sun the human eye can still see colour rather than using monochrome 'night' vision? Bob Shaw -------------------- Remember: Time Flies like the wind - but Fruit Flies like bananas!
|
|
|
Guest_Myran_* |
May 16 2006, 03:13 PM
Post
#21
|
Guests |
QUOTE Dilo wrote: .....but I strongly suspect termination shock is very close... or already passed! What you retold makes me wonder if that might be the case, and Voyager 2 might have reached the heliopause. Thank you or the heads up. |
|
|
May 23 2006, 08:56 PM
Post
#22
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Podcast Advisory May 23, 2006
Voyager: Still Going Strong After Nearly 30 Years NASA's twin Voyager spacecraft are beaming back new information about the final frontier of our solar system, including evidence of "potholes" in the turbulent zone near the edge. A podcast, featuring an interview with Voyager Project Scientist Dr. Ed Stone of Caltech, is online at http://www.jpl.nasa.gov/multimedia/podcast/voyager-20060523/ . The interview includes information about the latest findings, as well as highlights from the past 29 years of the Voyagers' journeys through space. More information on the Voyager spacecraft is available at http://voyager.jpl.nasa.gov/ and www.nasa.gov/voyager . Voyager 1 and 2 launched in 1977 on a mission to study the outer planets of our solar system, and they are now on their way to becoming the first spacecraft to leave our solar system. Additional JPL podcasts are at http://www.jpl.nasa.gov/multimedia/indexPod.cfm . -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
May 23 2006, 09:47 PM
Post
#23
|
|
Senior Member Group: Members Posts: 2921 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
[quote name='ljk4-1' date='May 23 2006, 10:56 PM' post='55471']
Voyager 1 and 2 launched in 1977 on a mission to study the outer planets of our solar system, and they are now on their way to becoming the first spacecraft to leave our solar system. I thought Pioneer 10 & 11 were considered been the first. By the way, Ed Stone was already there at last encounter with Neptune back in 1989. He's got to have faith in what he does to carry out the VIM (is that correct Voyager Insterstellar Mission ?) since it's apparently look less rewarding after "The Grand Tour". Hat off Mister Stone. -------------------- |
|
|
May 23 2006, 10:20 PM
Post
#24
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Climber, Pioneer didn't reached the heliopause because they are slower.
This is clear looking to distances from Sun, calculated by Solar System Simulator and ranked in descending order: Voyager-1: 99.2 AU Pioneer-10: 90.6 AU Voyager-2: 79.7 AU Pioneer-11: 69.9 AU (hey, they are almost equally spaced in this moment!) In particular, Pioneer-10 was surpassed by Voyager-1 several years ago and, anyway, now is inactive... Thanks, ljk4-1 for the interview highlight. The words of Dr. Ed Stone confirm that Voyager entered in a new region as I suspected, but still to reach the heliopause which should be 5 AU ahead! -------------------- I always think before posting! - Marco -
|
|
|
May 24 2006, 06:31 PM
Post
#25
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Voyager 2 Detects Odd Shape of Solar System's Edge
http://www.space.com/scienceastronomy/0605...here_shape.html Voyager 2 could pass beyond the outermost layer of our solar system, called the "termination shock," sometime within the next year, NASA scientists announced at a media teleconference today. -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
May 24 2006, 10:02 PM
Post
#26
|
|
Senior Member Group: Members Posts: 2921 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
[quote name='dilo' date='May 24 2006, 12:20 AM' post='55486']
Climber, Pioneer didn't reached the heliopause because they are slower. This is clear looking to distances from Sun, calculated by Solar System Simulator and ranked in descending order: Voyager-1: 99.2 AU Pioneer-10: 90.6 AU Voyager-2: 79.7 AU Pioneer-11: 69.9 AU (hey, they are almost equally spaced in this moment!) In particular, Pioneer-10 was surpassed by Voyager-1 several years ago and, anyway, now is inactive... Thanks Dilo. Doesn't show very well in the numbers anyway. Pioneer 10 deserve to has been the first one to be launched with an interstellar "destination" (as a by product), and Pionner 11 the second... and they will. -------------------- |
|
|
Guest_PhilCo126_* |
May 26 2006, 07:01 PM
Post
#27
|
Guests |
The greatest traveller of all times !
|
|
|
Guest_Analyst_* |
May 27 2006, 06:39 AM
Post
#28
|
Guests |
Do you have a link to the press kit? Or a press kit etc. of any of the other encounters?
Analyst |
|
|
May 27 2006, 09:06 PM
Post
#29
|
|
Member Group: Members Posts: 531 Joined: 24-August 05 Member No.: 471 |
Based on Solar System Simulator, Voyager-2 is only 79.6AU from Sun: considering also the unfavorable heading direction, is too early for a termination shock encounter (but not impossible, it depends also from solar activity!). Meanwhile, it is interesting to highlight that Voyager-1 is now only 130million Km from the 100 AU milestone! Should happens at mid August... I have to prepare some champagle bottle Yes, it should happens on August 17, 2006! - http://voyager.jpl.nasa.gov/science/Vgrlocations.pdf -------------------- - blue_scape / Nico -
|
|
|
Jun 1 2006, 02:46 PM
Post
#30
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Voyager Data May Reveal Trajectory Of Solar System
Newport Beach CA (SPX) Jun 01, 2006 Nearly 30 years after launch, the two Voyager spacecraft are still operational and returning useful data. In their early years they produced some of the first close up images of the large outer planets. http://www.spacedaily.com/reports/Voyager_...lar_System.html -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Jun 1 2006, 03:35 PM
Post
#31
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
PHYSICS NEWS UPDATE
The American Institute of Physics Bulletin of Physics News Number 778 May 26, 2006 by Phillip F. Schewe, Ben Stein, and Davide Castelvecchi www.aip.org/pnu THE MISSHAPEN SOLAR SYSTEM. Having traveled far beyond the planets in their 28.5-year journey, the two Voyager spacecraft are providing new information on the heliosphere, the teardrop-shaped bubble that separates the solar system from interstellar space. At this week's Joint Assembly Meeting in Baltimore of the American Geophysical Union (AGU) and several other geophysics-related societies, Ed Stone of Caltech reported that the heliosphere is deformed, according to Voyager observations, with the teardrop's rounded edge bulging at the top (the northern hemisphere of the solar system) and squashed at the bottom (the southern hemisphere). (See pictures and movies at http://www.nasa.gov/vision/universe/solars...er_2006agu.html ) As Rob Decker of Johns Hopkins University Applied Physics Laboratory explained, the asymmetry is due to a magnetic field from interstellar space pushing on the southern hemisphere. The field is about 1/100,000 the strength of Earth's field but its effects can be felt for billions of miles, since it is acting over a large area on the very dilute gas at the solar system's edge. The interstellar field even squashes an important spherical zone inside the heliosphere, called the termination shock. Analogous to the circle that forms when water splatters on a sink, the termination shock represents the boundary at which the rapidly traveling solar wind (the stream of charged gas from the sun) slows down abruptly and piles up. Voyager 2's measurements indicate that the southern part of the termination sphere might be a billion miles closer to the sun than the northern part. Moreover, forces from the solar wind cause the termination shock to breathe in and out roughly every dozen years. Voyager 1 has already ventured beyond the termination shock, to the heliosheath, the region where solar wind and interstellar gas mix. So in a way, the end of the solar system is not clearly defined. Stone guesses it could be another 10 years (3-4 billion miles) before the two spacecraft pass through the heliopause (the very outermost boundary of the heliosphere) and enter purely interstellar space. The spacecraft have about another 15 years of power left in them. (Session SH02 at meeting; see http://www.agu.org/meetings/ja06/?content=search) Do you have a link to the press kit? Or a press kit etc. of any of the other encounters? Analyst There is the Voyager Neptune Travel Guide online: http://ntrs.nasa.gov/archive/nasa/casi.ntr..._1990004096.pdf Other online Voyager documents from NASA can be found here by scrolling all the way down (the spacecraft are listed in alphabetical order): http://www.geocities.com/bobandrepont/unmannedpdf.htm -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Jun 9 2006, 02:59 AM
Post
#32
|
|
Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Voyager Reports March 3, 2006 to March 24, 2006 Available
http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
|
|
Sep 23 2006, 09:40 AM
Post
#33
|
|
Junior Member Group: Members Posts: 21 Joined: 17-August 06 Member No.: 1048 |
There's a new story at science.nasa.gov about some of the things Voyager 1 has found within the heliosheath. Magnetic turbulence, a slower than expected solar wind, and unexpected anomalous cosmic ray intensities are the main things mentioned. I hope this helps make the case for continued funding.
|
|
|
Apr 17 2008, 04:45 PM
Post
#34
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
This is not exactly a new: Voyager 2 entered the heliosheath on August 30, 2007.
http://voyager.jpl.nasa.gov/news/voyager_squashed.html However, incredibly, I completely ignored the event on this page and only now I "discovered" it by looking to these eloquent plots: http://web.mit.edu/space/www/voyager/voyag...plot_recent.gif (in the past, I was looking more often to these data but in recent months I'm more and more busy ). Looking to this Forum section, it seems nobody noticed it... cannot believe anyone missed it like me! Addendum: based on Solar System Simulator, cross occurred at 83.7 AU from sun, about 10 AU closer than Voyager-1! -------------------- I always think before posting! - Marco -
|
|
|
Apr 17 2008, 09:11 PM
Post
#35
|
||||
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Further infos: As you know, contrary to his brother, Voyager 2 has a working Plasma Science instrument that can directly measure the velocity, density and temperature of the solar wind.
I downloaded hourly data from this plasma science page. Following plots shows trend of measured proton speed, thermal speed (temperature) and density (second plot is a temporal enlargement covering the transition (window is 0.1 years or 36.5 days large): As mentioned in the article, Voyager-2 had at least five shock crossings over a couple of days; perhaps they are the density peaks visible in second plot. QUESTION: why there is a so large hiatus (11 days) in the data immediately after this event??? Too strange for a coincidence! They also found a much lower temperature beyond the shock than was predicted; anyway, based on following scatter plots (referred to data in the narrow temporal window of second plot above) there is a good correlation (almost inverse-square) between these twoparameters: Any comment is welcomed! -------------------- I always think before posting! - Marco -
|
|||
|
||||
Apr 17 2008, 09:31 PM
Post
#36
|
|
Senior Member Group: Members Posts: 1639 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
I saw a nice talk that Ed Stone gave on this topic three days ago. It will be interesting to follow along for a decade or so to see what the magnetic field looks like when Voyager gets completely into the interstellar medium.
-------------------- Steve [ my home page and planetary maps page ]
|
|
|
Jul 2 2008, 08:18 PM
Post
#37
|
|
Member Group: Members Posts: 754 Joined: 9-February 07 Member No.: 1700 |
(edit: of course this is old news to UMSF thread readers!)
The solar system is 'dented' as reported in this CNN Article. I'm curious about how they refer to 'north' and 'south', and whether the motion of the Sun through the Milky Way impacts the escape velocities of the Voyagers. (2nd edit: I thought I had asked the velocity question somewhere before, and found that dmuller provided insight in this post over in the New Horizons thread. thank you dmuller!) |
|
|
Jul 27 2008, 02:12 PM
Post
#38
|
|
Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
In the latest issue of Astronomy & Astrophysics
Imaging the heliosheath using HSTOF energetic neutral atoms and Voyager 1 ion data |
|
|
Sep 24 2008, 06:48 AM
Post
#39
|
|
Member Group: Members Posts: 293 Joined: 22-September 08 From: Spain Member No.: 4350 |
You may want to look at Voyager 2 wind speed data:
http://web.mit.edu/afs/athena/org/s/space/...yager_data.html There was a nice spike last month, from ~225 km/s to ~325 km/s, the fastest speed since it crossed the termination shock. |
|
|
Guest_PhilCo126_* |
Oct 27 2008, 07:07 PM
Post
#40
|
Guests |
|
|
|
Nov 1 2008, 04:15 PM
Post
#41
|
|
Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
The latest issue of Astronomy & Astrophystics (v491 n1) has some articles about heliospheric science, including results from Voyager, Ulysses, Cassini, Nozomi etc.
|
|
|
Nov 1 2008, 09:14 PM
Post
#42
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Grazie, Paolo. Very interesting!
-------------------- I always think before posting! - Marco -
|
|
|
Guest_Enceladus75_* |
Nov 3 2008, 06:07 PM
Post
#43
|
Guests |
I'm curious to know what science instruments are still functional on each Voyager. I'm aware that the cameras are now permanently turned off Voyager 2 has some more capability at measuring fields and particles over Voyager 1, but what instruments are actually still operational?
And for how long are they expected to remain operational? |
|
|
Nov 3 2008, 06:25 PM
Post
#44
|
|
Member Group: Members Posts: 293 Joined: 22-September 08 From: Spain Member No.: 4350 |
|
|
|
Nov 3 2008, 06:41 PM
Post
#45
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
and about instruments (from wikipedia):
As of the present date, the Voyager 2 and Voyager 1 scan platforms, including all of the platform instruments, have been powered down. The ultraviolet spectrometer (UVS) on Voyager 1 was active until 2003, when it too was deactivated. Gyro operations will end in 2010 for Voyager 2 and 2011 for Voyager 1. Gyro operations are used to rotate the probe 360 degrees six times a year to measure the magnetic field of the spacecraft, which is then subtracted from the magnetometer science data. -------------------- I always think before posting! - Marco -
|
|
|
Guest_Enceladus75_* |
Nov 3 2008, 07:42 PM
Post
#46
|
Guests |
Thanks guys. So it seems like both Voyagers will still have most of the fields and particles instruments active for the next decade or so.
|
|
|
Nov 4 2008, 06:24 AM
Post
#47
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Yes.
More precisely, with the exception of the Voyager 1 Plasma Science instrument (which is turned off to accommodate UVS observations), all instruments are working well and are capable of continuing operations at least until 2020. However, due to termination of gyro operations about 7 years from now, it will be impossible to calibrate the magnetometer instrument and, more important, spacecrafts could loose orientation anticipating communications blackout with Earth... so, let's cross our fingers! -------------------- I always think before posting! - Marco -
|
|
|
Sep 30 2009, 09:23 AM
Post
#48
|
|
Newbie Group: Members Posts: 4 Joined: 27-June 08 Member No.: 4241 |
Voyager Reports March 3, 2006 to March 24, 2006 Available http://voyager.jpl.nasa.gov/mission/weekly-reports/index.htm I had a look at this page today and it seems the last report was made on the 31st of July? Is there a problem with the probes? |
|
|
Sep 30 2009, 09:57 AM
Post
#49
|
|
Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
They always update these pages in batches with some time delay. No worries.
|
|
|
Dec 13 2010, 11:26 PM
Post
#50
|
|
Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
Voyager 1 Sees Solar Wind Decline; Edges Closer to Interstellar Space (2010-12-13)
http://solarsystem.nasa.gov/news/display.cfm?News_ID=36121 -------------------- |
|
|
Dec 14 2010, 03:29 AM
Post
#51
|
|
Member Group: Members Posts: 754 Joined: 9-February 07 Member No.: 1700 |
From the 12/14 Space Daily article (wait - that's tomorrow! hehe)
QUOTE Scientists suspect the solar wind has been turned sideways by the pressure from the interstellar wind in the region between stars. Questions for more studied UMSFers: The space daily article has an image that implies our sun's heliosheath has a huge tail. Is that tail due to the sun's motion around the galactic center? Is Voyager 1 at the 'front' edge? Is Voyager 2 heading down the tail side? |
|
|
Dec 14 2010, 04:28 AM
Post
#52
|
|
Member Group: Members Posts: 555 Joined: 27-September 10 Member No.: 5458 |
I think this article could help:
http://www.sciencedaily.com/releases/2009/...91016142056.htm Also: http://www.sciencedaily.com/releases/2009/...91016101807.htm -------------------- |
|
|
Dec 14 2010, 12:14 PM
Post
#53
|
|
Newbie Group: Members Posts: 9 Joined: 23-June 09 From: Leyland U.K. Member No.: 4834 |
|
|
|
Apr 14 2011, 12:13 PM
Post
#54
|
|
Junior Member Group: Members Posts: 59 Joined: 25-December 05 From: Stevens Point, Wisconsin, USA Member No.: 619 |
Nice article about Edward Stone in today's LA Times:
"Voyager 1 on the edge, and so is he" http://www.latimes.com/news/local/la-me-04...0,4527527.story |
|
|
Apr 14 2011, 04:43 PM
Post
#55
|
|
Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
Thanks Rogelio - nice article
Ed has quite some CV over the last four decades!! I sincerely hope he's around to see V1 coast into interstellar space proper. Jase |
|
|
Jun 10 2011, 02:11 AM
Post
#56
|
|
Member Group: Members Posts: 599 Joined: 26-August 05 Member No.: 476 |
|
|
|
Jun 16 2011, 08:38 AM
Post
#57
|
|
Member Group: Members Posts: 241 Joined: 16-May 06 From: Geneva, Switzerland Member No.: 773 |
Some good news from outer space :
"Voyager 1 could cross over into the frontier of interstellar space at any time and much earlier than previously thought" http://voyager.jpl.nasa.gov/news/recalculating_space.html Links to the journal Nature : http://www.nature.com/news/2011/110615/ful...s.2011.370.html http://www.nature.com/nature/journal/v474/...nature10115.pdf Best regards, Marc. |
|
|
Jul 26 2011, 04:52 AM
Post
#58
|
|
Junior Member Group: Members Posts: 95 Joined: 5-September 07 Member No.: 3662 |
Hi all,
I'm working on an article on the Voyagers, and have noticed that the last weekly status updates on the Voyager website were published in April. Does anybody know if they're normally sent up in batches? Thanks Jeff |
|
|
Jul 26 2011, 07:21 AM
Post
#59
|
|
Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
Yes, last time I checked, they get put on the website in large batches.
|
|
|
Dec 2 2011, 06:07 AM
Post
#60
|
|
Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
today on Science express: Voyager Measurements of Hydrogen Lyman-α Diffuse Emission from the Milky Way
|
|
|
Dec 2 2011, 08:37 AM
Post
#61
|
|
Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
Great, still doing good science!
|
|
|
Dec 3 2011, 01:30 AM
Post
#62
|
|
Member Group: Members Posts: 200 Joined: 20-November 05 From: Mare Desiderii Member No.: 563 |
Curious to know if the measurements form anything that could be described as an image. Does the full article say -- anyone have Science access? (I can't tell from the free online supplement.)
Measurements are said to be taken with the ultraviolet spectrometer (UVS). This page quotes FOV as 0.10° × 0.87°, so maximum spatial resolution would be pretty coarse. From hints in the supplement, I guess the data are much coarser. This page (date unknown) says: "data is being collected from the Ultraviolet Spectrometer Subsystem (UVS). While there are no science investigation teams associated with this instrument, the captured data is made available to interested scientists." If this was true at the time the relevant measurements were taken, I guess they might not have been chosen with this investigation in mind? New Scientist says the instruments have since been turned off (corroborated by this page: V1 1998, V2 2002). |
|
|
Dec 3 2011, 02:49 AM
Post
#63
|
|
Senior Member Group: Members Posts: 1583 Joined: 14-October 05 From: Vermont Member No.: 530 |
http://vega.lpl.arizona.edu/voyager_uvs/instrument.html
It's pulse counting on the 128 channels that form the spectrum. From the supplement: QUOTE For our specific purpose of a high precision and bias-free Ly determination we have devised a new reduction and analysis pipeline, improved from the technique used earlier (33). The Voyager UVS (Ultra-Violet Spectrometer) has a field of view of 0.1x0.87 defined by a mechanical grill collimator. Light that passes through the collimator reaches a concave grating, which disperses and focusses the light onto the microchannel plate (MCP) detector. A single photo-electron created at the input of the MCP generates a pulse of many electrons at the output, and this charge is collected on a linear array of 128 elongated anodes (channels) that correspond to the 540 to 1700 Å range. One anode covers 9.26 Å. Charges on the anodes are periodically sampled and subjected to threshold detection; detected events are summed into 128 corresponding memory locations to form a spectrum. So no, not really a picture. And that is coupled with two Azimuth directions. |
|
|
Dec 3 2011, 08:54 AM
Post
#64
|
|
Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
Curious to know if the measurements form anything that could be described as an image. Does the full article say -- anyone have Science access? (I can't tell from the free online supplement.) there is an image in the paper (fig. 2, for those having access) showing "Scan data point directions superimposed on" a hydrogen-alpha map of the sky. Scan data points are colorized to indicate "the intensity of the continuum, with red indicating its absence and blue the most intense". no real image, actually... as for the date scans were taken, Voyager 1 operated between 1993 and mid-2003 and V2 between 1993 and mid-1998. |
|
|
Dec 13 2011, 10:43 AM
Post
#65
|
|
Member Group: Members Posts: 241 Joined: 16-May 06 From: Geneva, Switzerland Member No.: 773 |
It's getting really exiting !! Not long to wait now before historical entry into the interstellar medium !!
NASA'S VOYAGER HITS NEW REGION AT SOLAR SYSTEM EDGE http://voyager.jpl.nasa.gov/news/new_region.html Best regards, Marc. |
|
|
Dec 13 2011, 07:03 PM
Post
#66
|
|
Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
-------------------- Space Enthusiast Richard Hendricks
-- "The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke Mother Nature is the final inspector of all quality. |
|
|
Dec 13 2011, 08:37 PM
Post
#67
|
|
Member Group: Members Posts: 241 Joined: 16-May 06 From: Geneva, Switzerland Member No.: 773 |
Hehehe ! Oups !! This loss of C was really not deliberate !!
|
|
|
Dec 13 2011, 09:59 PM
Post
#68
|
|
Senior Member Group: Moderator Posts: 3233 Joined: 11-February 04 From: Tucson, AZ Member No.: 23 |
I wouldn't call that a Freudian slip, but that certainly goes on the list of best puns (albeit unintentional) of the year.
-------------------- &@^^!% Jim! I'm a geologist, not a physicist!
The Gish Bar Times - A Blog all about Jupiter's Moon Io |
|
|
Dec 17 2011, 07:14 PM
Post
#69
|
|
Member Group: Members Posts: 115 Joined: 8-January 05 From: Austin | Texas Member No.: 138 |
It's amazing that the science coming from the Voyagers hasn't really egressed in the 30+ years they've been in service.
|
|
|
Jun 20 2012, 07:03 PM
Post
#70
|
|
Member Group: Members Posts: 241 Joined: 16-May 06 From: Geneva, Switzerland Member No.: 773 |
|
|
|
Jun 21 2012, 04:58 AM
Post
#71
|
||
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Ever closer... I think they refers, in particular, to high energy proton flux: extracted from here: v1_1d_08_on_8ion.pdf ( 106.9K ) Number of downloads: 786 -------------------- I always think before posting! - Marco -
|
|
|
||
Aug 7 2012, 03:49 PM
Post
#72
|
|
Member Group: Members Posts: 241 Joined: 16-May 06 From: Geneva, Switzerland Member No.: 773 |
And more signs that "we" are almost in the interstellar medium...
http://voyager.jpl.nasa.gov/news/signs_changing_fast.html Best regards, Marc. |
|
|
Sep 1 2012, 07:04 AM
Post
#73
|
|
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
At the end of August we had another two drops of low-energy protons, even deeper than one month ago!
http://sd-www.jhuapl.edu/VOYAGER/images/vg...d_avg_09_on.pdf -------------------- I always think before posting! - Marco -
|
|
|
Sep 5 2012, 07:13 AM
Post
#74
|
|
Senior Member Group: Admin Posts: 3108 Joined: 21-December 05 From: Canberra, Australia Member No.: 615 |
Voyager 1 marks 35 years since launch and joining Voyager 2 on the Grand Tour of the Solar System.
http://voyager.jpl.nasa.gov/news/voyager_35.html A new banner to mark the milestone Sail on lil' Voyagers! Sail on! |
|
|
Sep 5 2012, 07:33 AM
Post
#75
|
|
Member Group: Admin Posts: 976 Joined: 29-September 06 From: Pasadena, CA - USA Member No.: 1200 |
I think that Voyagers are the coolest mission. Whenever I go to the Von Karman here at JPL where they have a replica I'm always amazed by their size.
Paolo -------------------- Disclaimer: all opinions, ideas and information included here are my own,and should not be intended to represent opinion or policy of my employer.
|
|
|
Sep 5 2012, 06:16 PM
Post
#76
|
|
Senior Member Group: Members Posts: 1729 Joined: 3-August 06 From: 43° 35' 53" N 1° 26' 35" E Member No.: 1004 |
on the next issue of Nature
Voyager’s long goodbye No meridional plasma flow in the heliosheath transition region the latter requires a subscription |
|
|
Sep 5 2012, 06:42 PM
Post
#77
|
|
Member Group: Members Posts: 655 Joined: 22-January 06 Member No.: 655 |
|
|
|
Sep 14 2012, 01:13 PM
Post
#78
|
||
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
I think this combined plot speaks by itself:
V1 is definitively inside a totally new region... Source: http://voyager.gsfc.nasa.gov/heliopause/he...recenthist.html -------------------- I always think before posting! - Marco -
|
|
|
||
Sep 30 2012, 06:07 PM
Post
#79
|
|
Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
It really looks like it.
That particle/proton rate have stayed low for 2 more weeks, whereas the galactic cosmic rays continue to climb slowly. And turning of the spacecraft to look for any possible sideway movement did show that the particles were not moving sideways either. (Also described in the summary linked by Paolo.) Isn't that exactly the conditions to expect at the boundary of the heliopause? Now data from IBEX suggest there might be no bow shock zone at all. So all will depend on how deep this area might be, after that Voyager 1 might very well be in true Interstellar space. Related story 'The little motor that could' |
|
|
Sep 30 2012, 06:49 PM
Post
#80
|
||
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Thanks for the link, TheAnt!
This recall me to update the plot: After two more weeks, initial impression became a robust trend! -------------------- I always think before posting! - Marco -
|
|
|
||
Nov 30 2012, 07:27 PM
Post
#81
|
|
Member Group: Members Posts: 222 Joined: 7-August 12 From: Garberville, CA Member No.: 6500 |
NASA will host a media teleconference at 11 a.m. PST (2 p.m. EST) on Monday, Dec. 3, to discuss the latest findings and travels of NASA's Voyager 1 spacecraft. MORE HERE
-------------------- "We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time." -T.S. Eliot
|
|
|
Nov 30 2012, 10:01 PM
Post
#82
|
|
Member Group: Members Posts: 910 Joined: 4-September 06 From: Boston Member No.: 1102 |
Dilo
Are your graph labels are correct >70 and >0.5 not >70 and <0.5?? -------------------- |
|
|
Nov 30 2012, 10:43 PM
Post
#83
|
|
Senior Member Group: Members Posts: 1431 Joined: 26-July 08 Member No.: 4270 |
That's what the original graphs say.
http://voyager.gsfc.nasa.gov/heliopause/he...ause/v1la1.html http://voyager.gsfc.nasa.gov/heliopause/he...ause/v1pgh.html -------------------- -- Hungry4info (Sirius_Alpha)
|
|
|
Dec 1 2012, 03:33 AM
Post
#84
|
|
Member Group: Members Posts: 910 Joined: 4-September 06 From: Boston Member No.: 1102 |
What am I missing. >70 is also >0.5, so how can >70 be going up the last month and >0.5 be going down????? Never mind--two different detectors measuring different types of particles, not one detector measuring two energy ranges.
-------------------- |
|
|
Dec 1 2012, 10:17 AM
Post
#85
|
|
Founder Group: Chairman Posts: 14432 Joined: 8-February 04 Member No.: 1 |
However - the value of >70 is small compared to >0.5
It's risen from only 2 to 2.3 Whereas the >0.5 has dropped from 25 to about 2.3 i.e. - the amount of particles between 0.5 and 70 has dropped to essentially zero. |
|
|
Dec 1 2012, 04:27 PM
Post
#86
|
||
Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
Dilo Are your graph labels are correct >70 and >0.5 not >70 and <0.5?? Labels were correct (copied from original) but their postions on vertical axes were wrong! This is the correct (and updated) 1-year trend: Sorry for mistake! -------------------- I always think before posting! - Marco -
|
|
|
||
Dec 3 2012, 07:03 PM
Post
#87
|
|
Senior Member Group: Members Posts: 2086 Joined: 13-February 10 From: Ontario Member No.: 5221 |
|
|
|
Dec 3 2012, 07:31 PM
Post
#88
|
|
Senior Member Group: Moderator Posts: 4279 Joined: 19-April 05 From: .br at .es Member No.: 253 |
News release: NASA Voyager 1 Encounters New Region in Deep Space.
QUOTE December 03, 2012
PASADENA, Calif. -- NASA's Voyager 1 spacecraft has entered a new region at the far reaches of our solar system that scientists feel is the final area the spacecraft has to cross before reaching interstellar space. ... |
|
|
Dec 6 2012, 08:07 PM
Post
#89
|
|
Junior Member Group: Members Posts: 78 Joined: 16-October 12 From: Pennsylvania Member No.: 6711 |
So much for there being a clear cutoff point
|
|
|
Dec 7 2012, 02:26 AM
Post
#90
|
|
Founder Group: Chairman Posts: 14432 Joined: 8-February 04 Member No.: 1 |
|
|
|
Dec 7 2012, 06:49 AM
Post
#91
|
|
Senior Member Group: Members Posts: 2086 Joined: 13-February 10 From: Ontario Member No.: 5221 |
I think this time they're very sure this is the last section before true interstellar space (in terms of particles, not gravity). It was described as the 'off-ramp' to the stars in the recent teleconference. And the team will know it when they see it.
Once Voyager 2 crosses into this same area, we might even be able to guesstimate the large-scale shape of this 'highway'. |
|
|
Dec 7 2012, 12:07 PM
Post
#92
|
|
Founder Group: Chairman Posts: 14432 Joined: 8-February 04 Member No.: 1 |
There will be no sharp cut off of gravity - why do you mention that?
|
|
|
Dec 7 2012, 05:27 PM
Post
#93
|
|
Junior Member Group: Members Posts: 78 Joined: 16-October 12 From: Pennsylvania Member No.: 6711 |
What I meant is that the scientists told us there was a clear boundary between the heliosphere and the outside. First they said there was a blow shock. Now we know the Sun doesn't have one. Then they said that the boundary would be when the solar wind stopped and there would be a sharp increase in cosmic rays. And thats what we've seen. But now they say were still inside the heliosphere because of the magnetic orientation. This new "in-between" area.
The heliosphere is the edge of the suns magnetic field. I was led to think there would be a sharp boundary. Now it seems to depend of interpretation. Is the edge where the influx of cosmic rays begins, or is it when the sun's magnetic field gives way to the galactic magnetic field? Thats all. |
|
|
Dec 7 2012, 05:28 PM
Post
#94
|
|
Senior Member Group: Members Posts: 2086 Joined: 13-February 10 From: Ontario Member No.: 5221 |
I was replying to 0101Morpheus about whether there's a clear transition into interstellar space which the heliopause crossing will be. Yet it really depends on our definitions of solar system; the sun's gravitational influence will be felt much farther, tens of thousands of AU, while the high energy particle environment can and does change rapidly, as this recent discovery shows. The Oort cloud would be 'outside' our solar system by the latter particle definition, but clearly still gravitationally bound to the Sun.
|
|
|
Dec 7 2012, 05:32 PM
Post
#95
|
|
Junior Member Group: Members Posts: 78 Joined: 16-October 12 From: Pennsylvania Member No.: 6711 |
Seems we got our replies mixed up.
Yes I know the sun's gravity doesn't stop. You can keep going for a light year and still be inside its hills sphere. |
|
|
Dec 24 2012, 09:17 PM
Post
#96
|
|
Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
In the data for Voyager 2 we got a dip for the particle flux now in the first week of December then it had a small peak, to fold back down in about the same pace in the last days.
This might be similar as what we did see for V1 in August. However this is one "stay tuned" post of mine for those interested, a heads up that also V2 might get close to the boundary but that it's not quite there yet. Voyager 2 data page |
|
|
Dec 24 2012, 09:34 PM
Post
#97
|
|
Founder Group: Chairman Posts: 14432 Joined: 8-February 04 Member No.: 1 |
V2 is clearly in a very different environment to V1. V2 has had a very gradual decline over the past year to about 50% of initial levels. V1 was almost static at a fixed level until a very sudden and rapid decline by an order of magnitude in literally a day that bounced back and forth a little then dropped for good. Fascinating.
|
|
|
Dec 25 2012, 12:34 AM
Post
#98
|
|
Senior Member Group: Members Posts: 2086 Joined: 13-February 10 From: Ontario Member No.: 5221 |
Until New Horizons gets out there, these two are the only data points we have on what is certain to be complex large scale structures. Glad both are still functioning.
|
|
|
Dec 25 2012, 02:40 AM
Post
#99
|
|
Senior Member Group: Members Posts: 1583 Joined: 14-October 05 From: Vermont Member No.: 530 |
Until New Horizons gets out there, these two are the only data points we have on what is certain to be complex large scale structures. Glad both are still functioning. No magnetometer on NH, though. Going to be a very long time until another magnetometer heads out there. (Comments about exactly how far NH will get aside.) |
|
|
Jan 1 2013, 10:50 AM
Post
#100
|
|
Member Group: Members Posts: 495 Joined: 12-February 12 Member No.: 6336 |
V2 is clearly in a very different environment to V1. My little personal hypothesis is that it is the same environment, the graph certainly dropped like a rock for V1 - which made me pay attention that something had happened. V1 are heading in a direction nearly bulls eye on the solar apex (the direction which the sun are travelling) - so the sphere might be somewhat flattened there and the border zone itself compressed. But that V2 are entering it at a point nearly 90 degrees from the solar apex and so the process will take a longer time. Since my post the particle count have started to drop down again - but as said, my post were merely a heads-up I am fully aware from my own work not to build intricate theories on just a hump in a graph. =) |
|
|
Lo-Fi Version | Time is now: 23rd May 2024 - 02:16 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |