[ RadSafe ] News: The lasting efficiency and versitility of nuclear energy

[John Jacobus]

Story at
http://www.cnn.com/2006/TECH/space/05/23/voyager.2/index.html

About the plutonium power source, see
http://www.space.com/missionlaunches/top10_voyager_020820-7.html
--------------------------------

Voyager II detects solar system's edge
By Ker Than 
http://SPACE.com

Wednesday, May 24, 2006; Posted: 10:24 a.m. EDT (14:24
GMT) 

Voyager II is about 6.5 billion miles away and moving
at about 3.3 AU per year.  
 
RELATED
Interactive: Voyager I pushes into the final frontier 


• SPACE.com:  Top 10 Voyager facts 
http://www.space.com/missionlaunches/top10_voyager_020820-1.html
• SPACE.com:  Voyager images 
http://www.space.com/php/multimedia/imagegallery/igviewer.php?imgid=1567&gid=130&index=0
 
• NASA/Jet Propulsion Laboratory:  Voyager 
http://www.nasa.gov/mov/52704main_heliopause.mov

(SPACE.com) -- Voyager II 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
Tuesday.

The milestone, which comes about a year after Voyager
1's crossing, comes earlier than expected and suggests
to scientists that the edge of the shock is about one
billion miles closer to the sun in the southern region
of the solar system than in the north.

This implies that the heliosphere, a spherical bubble
of charged low-energy particles created by our sun's
solar wind, is irregularly shaped, bulging in the
northern hemisphere and pressed inward in the south.

Scientists determined that Voyager I was approaching
the termination shock when it began detecting charged
particles that were being pushed back toward the sun
by charged particles coming from outside our solar
system. This occurred when Voyager 1 was about 85 AU
from the sun. (Full story)

One AU is the distance between the Earth and the sun,
or 93 million miles.

In contrast, Voyager II began detecting returning
particles while only 76 AU from the sun.

"This tells us that the shock down where Voyager II is
must be closer the sun than where Voyager I is," said
Ed Stone, Voyager project scientist at the California
Institute of Technology in Pasadena.

The researchers think that the heliosphere's asymmetry
might be due to a weak interstellar magnetic field
pressing inward on the southern hemisphere.

"The [magnetic] field is only 1/100,000 of the field
on the Earth's surface, but it's over such a large
area and pushing on such a faint gas that it can
actually push the shock about a billion miles in,"
Stone explained.

Both Voyager spacecrafts were launched from Cape
Canaveral Air Force Station in Florida: Voyager II
headed out on August 20, 1977, Voyager I on September
5, 1977.

Currently, Voyager I is about 8.7 billion miles from
the sun and traveling at a speed of 3.6 AU per year
while 

Voyager II is about 6.5 billion miles away and moving
at about 3.3 AU per year. 

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+++++++++++++++++++
"You get a lot more authority when the workforce doesn't think it's amateur hour on the top floor."
GEN. MICHAEL V. HAYDEN, President Bush's nominee for C.I.A. director.

-- John
John Jacobus, MS
Certified Health Physicist
e-mail:  crispy_bird at yahoo.com

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