Starship Asterisk*

Eventually, the Voyagers will pass other stars. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Camelopardalis. In some 296,000 years, Voyager 2 will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky . The Voyagers are destined—perhaps eternally—to wander the Milky Way.

rstevenson wrote:
From a page linked from that NASA page I linked to,
I read this...

Eventually, the Voyagers will pass other stars. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Camelopardalis. In some 296,000 years, Voyager 2 will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky . The Voyagers are destined—perhaps eternally—to wander the Milky Way.

[url=http://www.nasa.gov/mission_pages/voyager/multimedia/pia13892Label.html][b][i]Voyagers in the Heliosheath (Artist Concept)[/i][/b][/url] - [i]Credit: NASA/JPL-Caltech[/i]

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Data from NASA's Voyager 1 spacecraft indicate that the venerable deep-space explorer has encountered a region in space where the intensity of charged particles from beyond our solar system has markedly increased. Voyager scientists looking at this rapid rise draw closer to an inevitable but historic conclusion - that humanity's first emissary to interstellar space is on the edge of our solar system.

"The laws of physics say that someday Voyager will become the first human-made object to enter interstellar space, but we still do not know exactly when that someday will be," said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. "The latest data indicate that we are clearly in a new region where things are changing more quickly. It is very exciting. We are approaching the solar system's frontier."

The data making the 16-hour-38 minute, 11.1-billion-mile (17.8-billion-kilometer), journey from Voyager 1 to antennas of NASA's Deep Space Network on Earth detail the number of charged particles measured by the two High Energy telescopes aboard the 34-year-old spacecraft. These energetic particles were generated when stars in our cosmic neighborhood went supernova.

"From January 2009 to January 2012, there had been a gradual increase of about 25 percent in the amount of galactic cosmic rays Voyager was encountering," said Stone. "More recently, we have seen very rapid escalation in that part of the energy spectrum. Beginning on May 7, the cosmic ray hits have increased five percent in a week and nine percent in a month."

This marked increase is one of a triad of data sets which need to make significant swings of the needle to indicate a new era in space exploration. The second important measure from the spacecraft's two telescopes is the intensity of energetic particles generated inside the heliosphere, the bubble of charged particles the sun blows around itself. While there has been a slow decline in the measurements of these energetic particles, they have not dropped off precipitously, which could be expected when Voyager breaks through the solar boundary.

The final data set that Voyager scientists believe will reveal a major change is the measurement in the direction of the magnetic field lines surrounding the spacecraft. While Voyager is still within the heliosphere, these field lines run east-west. When it passes into interstellar space, the team expects Voyager will find that the magnetic field lines orient in a more north-south direction. Such analysis will take weeks, and the Voyager team is currently crunching the numbers of its latest data set.

"When the Voyagers launched in 1977, the space age was all of 20 years old," said Stone. "Many of us on the team dreamed of reaching interstellar space, but we really had no way of knowing how long a journey it would be -- or if these two vehicles that we invested so much time and energy in would operate long enough to reach it."

Launched in 1977, Voyager 1 and 2 are in good health. Voyager 2 is more than 9.1 billion miles (14.7 billion kilometers) away from the sun. Both are operating as part of the Voyager Interstellar Mission, an extended mission to explore the solar system outside the neighborhood of the outer planets and beyond. NASA's Voyagers are the two most distant active representatives of humanity and its desire to explore.

[i]This artist's concept shows NASA's two Voyager spacecraft exploring a turbulent region of space known as the heliosheath, the outer shell of the bubble of charged particles around our sun. Image credit: NASA/JPL-Caltech [/i]

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Two of three key signs of changes expected to occur at the boundary of interstellar space have changed faster than at any other time in the last seven years, according to new data from NASA's Voyager 1 spacecraft.

For the last seven years, Voyager 1 has been exploring the outer layer of the bubble of charged particles the sun blows around itself. In one day, on July 28, data from Voyager 1's cosmic ray instrument showed the level of high-energy cosmic rays originating from outside our solar system jumped by five percent. During the last half of that same day, the level of lower-energy particles originating from inside our solar system dropped by half. However, in three days, the levels had recovered to near their previous levels.

A third key sign is the direction of the magnetic field, and scientists are eagerly analyzing the data to see whether that has, indeed, changed direction. Scientists expect that all three of these signs will have changed when Voyager 1 has crossed into interstellar space. A preliminary analysis of the latest magnetic field data is expected to be available in the next month.

"These are thrilling times for the Voyager team as we try to understand the quickening pace of changes as Voyager 1 approaches the edge of interstellar space," said Edward Stone, the Voyager project scientist based at the California Institute of Technology, Pasadena, Calif. "We are certainly in a new region at the edge of the solar system where things are changing rapidly. But we are not yet able to say that Voyager 1 has entered interstellar space."

The levels of high-energy cosmic ray particles have been increasing for years, but more slowly than they are now. The last jump -- of five percent -- took one week in May. The levels of lower-energy particles from inside our solar system have been slowly decreasing for the last two years. Scientists expect that the lower-energy particles will drop close to zero when Voyager 1 finally crosses into interstellar space.

"The increase and the decrease are sharper than we've seen before, but that's also what we said about the May data," Stone said. "The data are changing in ways that we didn't expect, but Voyager has always surprised us with new discoveries."

Voyager 1, which launched on Sept. 5, 1977, is 11 billion miles (18 billion kilometers) from the sun. Voyager 2, which launched on Aug. 20, 1977, is close behind, at 9.3 billion miles (15 billion kilometers) from the sun.

"Our two veteran Voyager spacecraft are hale and healthy as they near the 35th anniversary of their launch," said Suzanne Dodd, Voyager project manager based at NASA's Jet Propulsion Laboratory, Pasadena. "We know they will cross into interstellar space. It's just a question of when."

[i]An artist’s concept of the heliosphere (seen in blue, including a shocked region). The Earth is at 1 AU, and the two Voyager spacecraft are seen beyond 100 AU (the Cassini spacecraft at Saturn is also shown). A new study investigates what happens to interstellar dust that encounters the solar system and the Sun's heliosphere. [b](Credit: NASA/JHU APL)[/b][/i]

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The space between stars is not empty. It contains copious but diffuse amounts of gas and dust; in fact about 5-10% of the total mass of our Milky Way galaxy is in interstellar gas. About 1% of the mass of this interstellar material, quite a lot in astronomical terms, is in the form of tiny dust grains made predominantly of silicates (sand too is made of silicates), though some grains are also composed of carbon and other elements. Dust grains are important. They block visible light while emitting infrared light, and thus help determine what astronomers can see while controlling much of the energy balance in the interstellar medium (ISM) by virtue of the absorption and subsequent re-emission at longer wavelengths of light from stars. Dust is also essential to the chemistry that takes place in the ISM because it provides gas molecules with a surface on which to react with other molecules. Not least, dust contains a large fraction of many important elements in the universe like silicon, carbon, and iron. Moreover, astronomers think that at some stage in the evolution of new stars the dust around them will coagulate into large clumps -- the first step towards forming planets.

CfA astronomer Jonathan Slavin and a team of six other astronomers wondered what happens to interstellar dust when it wanders into the solar system and gets close enough to the Sun to fall under the influence of its radiation, winds, and gravity. They note that the Sun (and its planets) is moving through a low density cloud of partially ionized gas. This motion, together with the wind of particles that the Sun emits, produces a bow-shaped region called the heliosphere, the bow-shaped end of which is about 100 AU from the Sun (one AU is the average distance of the Earth from the Sun).

Writing in the latest issues of the Astrophysical Journal, the scientists report on the results of their theoretical models of the behavior of interstellar dust grains as the Sun moves through space. They build on in-situ observations of the heliosphere taken when the Voyager 1 and Voyager 2 spacecraft on their outward journey encountered the edges of the heliosphere, results that constrain its size and shape. Assuming typical grains made of olivine silicates, the team finds that the small grains (less than the wavelength of ultraviolet light) stay far away from the Sun, that gravity helps the large grains collect near the Sun, but that intermediate-sized grains - about the size of the wavelength of optical light - can actually pile up in diffuse structures at the edges of the heliosphere. The new results, besides providing important new information on dust grains in the solar system, suggest that radiation from these intermediate-sized grain structures could contaminate the images of the sky used to measure the cosmic backgrounds.

• Astrophysical Journal 760(1) 46 (2012 Nov 20) DOI: 10.1088/0004-637X/760/1/46
  arXiv.org > astro-ph > arXiv:1210.1127 > 03 Oct 2012

CfA astronomer Jonathan Slavin and a team of six other astronomers wondered what happens to interstellar dust when it wanders into the solar system and gets close enough to the Sun to fall under the influence of its radiation, winds, and gravity. They note that the Sun (and its planets) is moving through a low density cloud of partially ionized gas. This motion, together with the wind of particles that the Sun emits, produces a bow-shaped region called the heliosphere, the bow-shaped end of which is about 100 AU from the Sun (one AU is the average distance of the Earth from the Sun).

Writing in the latest issues of the Astrophysical Journal, the scientists report on the results of their theoretical models of the behavior of interstellar dust grains as the Sun moves through space. They build on in-situ observations of the heliosphere taken when the Voyager 1 and Voyager 2 spacecraft on their outward journey encountered the edges of the heliosphere, results that constrain its size and shape. Assuming typical grains made of olivine silicates, the team finds that the small grains (less than the wavelength of ultraviolet light) stay far away from the Sun, that gravity helps the large grains collect near the Sun, but that intermediate-sized grains - about the size of the wavelength of optical light - can actually pile up in diffuse structures at the edges of the heliosphere. The new results, besides providing important new information on dust grains in the solar system, suggest that radiation from these intermediate-sized grain structures could contaminate the images of the sky used to measure the cosmic backgrounds.

http://people.howstuffworks.com/groom-carry-bride1.htm wrote:
Why do grooms carry brides over the threshold?
by Josh Clark

<<Pan-culturally, brides seem to be considered lightning rods for misfortune. In addition to being susceptible to bad luck, brides' bodies also supposedly provide great havens for unattached spirits. Spirit intrusion is the notion that the spirits of the dead or living can live on unattached to their physical bodies and are thus able to enter the bodies of others. Once inside, a spirit can wreak havoc on the possessed, generating physical and mental illness. Belief in spirit intrusion continues in some cultures today, although it was much more widespread in the ancient world. In many of these early cultures, the threshold of the home was thought to be rife with unattached spirits. A bride was considered particularly vulnerable to spirit intrusion, especially through the soles of her feet. By carrying her into their home, the groom was covering all his bases by ensuring his new wife didn't bring along any unwanted spiritual guests into the house.>>

• Voyager 1 Encounters New Region in Deep Space
  NASA JPL-Caltech | 2012 Dec 03
  

  

  This artist's concept shows plasma flows around NASA's Voyager 1 spacecraft as it approaches interstellar space. Image credit: NASA/JPL-Caltech/JHU-APL

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• 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.
  
  Scientists refer to this new region as a magnetic highway for charged particles because our sun's magnetic field lines are connected to interstellar magnetic field lines. This connection allows lower-energy charged particles that originate from inside our heliosphere -- or the bubble of charged particles the sun blows around itself -- to zoom out and allows higher-energy particles from outside to stream in. Before entering this region, the charged particles bounced around in all directions, as if trapped on local roads inside the heliosphere.
  
  The Voyager team infers this region is still inside our solar bubble because the direction of the magnetic field lines has not changed. The direction of these magnetic field lines is predicted to change when Voyager breaks through to interstellar space. The new results were described at the American Geophysical Union meeting in San Francisco on Monday.
  
  "Although Voyager 1 still is inside the sun's environment, we now can taste what it's like on the outside because the particles are zipping in and out on this magnetic highway," said Edward Stone, Voyager project scientist based at the California Institute of Technology, Pasadena. "We believe this is the last leg of our journey to interstellar space. Our best guess is it's likely just a few months to a couple years away. The new region isn't what we expected, but we've come to expect the unexpected from Voyager."
  
  Since December 2004, when Voyager 1 crossed a point in space called the termination shock, the spacecraft has been exploring the heliosphere's outer layer, called the heliosheath. In this region, the stream of charged particles from the sun, known as the solar wind, abruptly slowed down from supersonic speeds and became turbulent. Voyager 1's environment was consistent for about five and a half years. The spacecraft then detected that the outward speed of the solar wind slowed to zero.
  
  The intensity of the magnetic field also began to increase at that time.
  
  Voyager data from two onboard instruments that measure charged particles showed the spacecraft first entered this magnetic highway region on July 28, 2012. The region ebbed away and flowed toward Voyager 1 several times. The spacecraft entered the region again Aug. 25 and the environment has been stable since.
  
  "If we were judging by the charged particle data alone, I would have thought we were outside the heliosphere," said Stamatios Krimigis, principal investigator of the low-energy charged particle instrument, based at the Johns Hopkins Applied Physics Laboratory, Laurel, Md. "But we need to look at what all the instruments are telling us and only time will tell whether our interpretations about this frontier are correct."
  
  Spacecraft data revealed the magnetic field became stronger each time Voyager entered the highway region; however, the direction of the magnetic field lines did not change.
  
  "We are in a magnetic region unlike any we've been in before -- about 10 times more intense than before the termination shock -- but the magnetic field data show no indication we're in interstellar space," said Leonard Burlaga, a Voyager magnetometer team member based at NASA's Goddard Space Flight Center in Greenbelt, Md. "The magnetic field data turned out to be the key to pinpointing when we crossed the termination shock. And we expect these data will tell us when we first reach interstellar space."
  
  Voyager 1 and 2 were launched 16 days apart in 1977. At least one of the spacecraft has visited Jupiter, Saturn, Uranus and Neptune. Voyager 1 is the most distant human-made object, about 11 billion miles (18 billion kilometers) away from the sun. The signal from Voyager 1 takes approximately 17 hours to travel to Earth. Voyager 2, the longest continuously operated spacecraft, is about 9 billion miles (15 billion kilometers) away from our sun. While Voyager 2 has seen changes similar to those seen by Voyager 1, the changes are much more gradual. Scientists do not think Voyager 2 has reached the magnetic highway.
  
  The Voyager spacecraft were built and continue to be operated by NASA's Jet Propulsion Laboratory, in Pasadena, Calif. Caltech manages JPL for NASA. The Voyager missions are a part of NASA's Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate at NASA Headquarters in Washington.
  
  For more information about the Voyager spacecraft, visit: http://www.nasa.gov/voyager and http://voyager.jpl.nasa.gov.

ritwik wrote:
Voyager 1 Encounters New Region in Deep Space
NASA | JPL-Caltech | JHU-APL | 2012 Dec 03

saturno2 wrote:Voyager 2 speed now
Distance from Earth to Voyager 2 , data of NASA
I have performed several calculations on speed of Voyager 2.
It gives me a result of 28 km/ sec aprox.
Is it true this speed?
Very big speed !!

On September 9, 2012, Voyager 2 was 99.077 AU (1.48217×1010 km; 9.2098×109 mi) from the Earth and 99.504 AU (1.48856×1010 km; 9.2495×109 mi) from the Sun; and traveling at 15.436 km/s (34,530 mph) (relative to the Sun)

rstevenson wrote:According to the Voyager 2 Wikipedia page...

On September 9, 2012, Voyager 2 was 99.077 AU (1.48217×1010 km; 9.2098×109 mi) from the Earth and 99.504 AU (1.48856×1010 km; 9.2495×109 mi) from the Sun; and traveling at 15.436 km/s (34,530 mph) (relative to the Sun)

Rob

saturno2 wrote:Voyager 1
Now. Distance from the Sun 18.4 billion of km
Speed 16.4 Km/sec ( aprox. ) Relative the Sun

Voyager 2
Now. Distance from the Sun 15.0 billion of km
Speed 15 km/sec ( aprox. ) Relative the Sun

With the Voyager spacecraft being mid-1970's technology, the available on-board memory for storing spacecraft sequence information is very limited by today's standards. A total of about 1500 18-bit words are available between the two Computer Command Subsystem (CCS) memories...

saturno2 wrote:One of the projects most inetersting me , are NASA´s Voyager 1 and 2
spacecraft.
The journey throught interstellar space.
It is the Humanity traveling outside the Solar System