"We cast this message
into the cosmos ... Of the 200 billion stars in the Milky Way galaxy, Some
- perhaps many - may have inhabited planet and space faring civilisations.
If one such civilisation intercepts Voyager and can understand these recorded
contents, here is our message: We are trying to survive our time so we may
live into yours. We hope some day, having solved the problems we face, to
join a community of Galactic Civilisations. This record represents our hope
and our determination and our goodwill in a vast and awesome universe."
U.S. President Jimmy Carter's official statement
placed on the Voyager spacecraft for its trip outside our solar system,
June 16, 1977
NASA's Voyager 1 has reached
the final frontier of our solar system,
having travelled through a
turbulent place where electrically charged particles from the Sun crash
into thin gas from interstellar space. (in 2005)
Astronomers tracking the little spaceship's 45 year journey from Earth ( in 2022)
know Voyager 1 has gone through a region
known as termination shock, some 14 billion kilometres from the Sun, and
entered an area called the heliosheath.
"Voyager 1 has entered the final lap on its race to
the edge of interstellar space," Edward Stone, Voyager project scientist
at the California Institute of Technology, said in a statement. (in 2005)
Voyager watchers theorised in (2006) that the
craft might be reaching this bumpy region of space when the charged solar
particles known as the solar wind seemed to slow down from a top speed of
2.4 million km/h.
This was expected at the area of termination shock, where
the solar winds were expected to decelerate as they bump up against gas
from the space beyond our solar system.
By monitoring the craft's speed and the increase in the
force of the solar wind, Voyager scientists now believe the craft has made
it through the shock and into the heliosheath.
Predicting the location of the termination shock was hard
because the precise conditions in interstellar space are unknown and the
termination shock can expand, contract and ripple, depending on changes
in the speed and pressure of the solar wind.
"Voyager's observations over the past few years show
the termination shock is far more complicated than anyone thought,"
said Eric Christian, a scientist with NASA's Sun-Solar System Connection
Voyager 1 and its twin spacecraft Voyager
2 were launched in 1977 on a mission to explore the giant planets Jupiter
and Saturn. The pair kept going, however, and the mission was extended.
At almost 70 times farther from the Sun than the
Earth, Voyager 1 is at the very edge of the Solar System. The Sun there
is only 1/5,000th as bright as here on Earth, so it is extremely cold, and
there is very little solar energy to keep the spacecraft warm or to provide
electrical power. " The reason they can
continue to operate at such great distances from the Sun is because we have
radioisotope thermal electric generators (RTGs) on the spacecraft that create
electricity and keep the spacecraft operating," JPL said.
"The fact that the spacecraft
is still returning data is a remarkable technical achievement."
Then, because its trajectory was designed to fly close
to Saturn's large moon Titan, Voyager 1's path was bent northward by Saturn's
gravity, sending the spacecraft out of the ecliptic plane -- the plane in
which all the planets except Pluto orbit the Sun.
"The Voyager mission
today presents an unequalled technical challenge. The spacecraft are now
so far from home that it takes nine hours and 36 minutes for a radio signal
travelling at the speed of light to reach Earth," said Ed B. Massey,
project manager for the Voyager Interstellar Mission at JPL. "That
signal, produced by a 20 watt radio transmitter, is so faint that the amount
of power reaching our antennas is 20 billion times smaller than the power
of a digital watch battery."
Although beyond the orbits of all the planets, the spacecraft
still are well within the boundary of the Sun's magnetic field, called the
heliosphere. Science instruments on both spacecraft sense signals that scientists
believe are coming from the outermost edge of the heliosphere, known as
The heliosphere results from the Sun's emitting a steady
flow of electrically charged particles called the solar wind. As the solar
wind expands supersonically into space in all directions, it creates a magnetised
bubble -- the heliosphere -- around the Sun. Eventually, the solar wind
encounters the electrically charged particles and magnetic field in the
interstellar gas. In this zone the solar wind abruptly slows down from supersonic
to subsonic speed, creating a termination shock. Before the spacecraft travel
beyond the heliopause into interstellar space, they will pass through this
"The data coming back from Voyager in 2007 indicated
that we are now passing through the termination shock ".
Reaching the termination shock
and heliopause is a major milestone for the mission because no spacecraft
have been there before and the Voyagers will gather the first direct evidence
of their structure. Encountering the termination shock and heliopause has
been a long-sought goal for many space physicists, and exactly where these
two boundaries are located and what they are like still remains a mystery.
Science data are returned to Earth in real-time to the
34 - meter Deep Space Network antennas located in California, Australia and
Spain. Both spacecraft have enough electricity and attitude (direction)
control propellant to continue operating until about 2025, when electrical
power produced by the RTGs will no longer support science instrument operation.
In December 2010
it was confirmed by JPL control that Voyager 1 had passed the reach of
the solar wind from our sun. It was always suspected that this (wind)
would turn sideways due to interstellar wind pushing against the
Heliosphere. Since June 2010 detection of this wind from Voyager 1 was
at zero, proving this.
Voyager 1 was approx. 17.3 Billion Kilometers for our sun ( in 2011 )
On March 8th
2011 Voyager 1 was commanded, from earth tracking stations, to change
it's position to detect the current direction of the solar wind.
A Test on February 2011 had determined that Voyager 1 could do this.
It rotated correctly to detect the solar wind, as commanded.
This was the first time Voyager 1 had responded to earth's commands since 1990.
1 responded as at June 2011, to Earth's commands, to re-orientate
itself to Alpha Centauri which is Voyager 1's guide star, so it can
begin sending transmissions back to earth.
This was a major step forward for Voyager 1.
At this time, Voyager 1 was 160 times farther from the Sun than the Earth -- around 17 billion
Voyager 1 was departing the Solar System
at a speed of 39,000 miles per hour (17.4 kilometres per second ). At the same time, Voyager 2 will be 5.1 billion miles (8.1 billion
kilometres) from Earth and was departing the Solar System at a speed of 35,000
miles per hour (15.9 kilometres per second).
In April 2013 it has been recorded that Voyager 1 finally left our solar system.
This was the first man made object to do this.
This means Voyager 1 is now in deep space beyond our solar system.
Over 23 Billion Kilometres away (in 2020)
instruments can operate until the RTG's can continue to provide power
and that will mean a gradual loss of instruments until about 2025 when
all functions may stop. Until then Voyager 1 will transmit information
to and from earth with a (about) 20 hour delay each way due to the
distance that Voyager 1 has from Earth.
Wherever they go, the Voyagers
each carry a golden phonograph record which bears messages from Earth, including
natural sounds of surf, wind, thunder and animals. There are also musical
selections, spoken greetings in 55 languages, along with instructions and
equipment on how to play the record.
Along with this is a picture
of Man and Woman, our planet, it's basic descriptions, our solar system
and items of interest like Money Systems (currency, banknotes).
A retired high ranking military general was
asked about UFO's on a current affairs TV show once.
He stated that he would not give any information
whatsoever on the subject but added that it was of great interest that images
and descriptions of our people, planet and solar system were placed aboard
the Voyager spacecraft.
He stated " If we are
definitely alone in the universe why did we do all this ? "
We read writings that were written on walls,
in caves, tombs, written many many many years ago in a language we do not
readily understand. We try and decipher them. Usually we manage to do that.
Perhaps the same will happen with the Voyager