Over the hills & far away!
Amazing, voyager 1 is now
the furthest man mad object in space. How far will it go? Where
will it end up? Will it be detected when it leaves our solar
system by some friendly aliens? Who know, but the final frontier
is about to be broken!
Just close your eyes and
actually try to comprehend how far they really are away from
you, and the breakneck speed at which they are travelling. In
comparison remember that it is unlikely that you will ever
travel further than the distance to our own moon and back in
your entire life...
Nasa Press Release
In a
dark, cold, vacant neighbourhood near the very edge of our solar
system, the Voyager 1 spacecraft is set to break another record
and become the explorer that has travelled farthest from home.
At
approximately 2:10 p.m. Pacific time on February 17, 1998,
Voyager 1, launched more than two decades ago, will cruise
beyond the Pioneer 10 spacecraft and become the most distant
human-created object in space at 10.4 billion kilometres (6.5
billion miles.) The two are headed in almost opposite directions
away from the Sun. As with other spacecraft travelling past the
orbit of Mars, both Voyager and Pioneer derive their electrical
power from onboard nuclear batteries.
"For
25 years, the Pioneer 10 spacecraft led the way, pressing the
frontiers of exploration, and now the baton is being passed from
Pioneer 10 to Voyager 1 to continue exploring where no one has
gone before," said Dr. Edward C. Stone, Voyager project
scientist and director of NASA's Jet Propulsion Laboratory.
"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 we 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," Stone said. "The fact that the spacecraft is still
returning data is a remarkable technical achievement."
Voyager 1 was launched from Cape Canaveral on September 5, 1977.
The spacecraft encountered Jupiter on March 5, 1979, and Saturn
on November 12, 1980.
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.
Launched on March 2, 1972, the Pioneer 10 mission officially
ended on March 31, 1997. However NASA's Ames Research Center,
Moffet Field, CA, intermittently receives science data from
Pioneer as part of a training program for flight controllers of
the Lunar Prospector spacecraft now orbiting the Moon.
"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. "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,"
Having completed their planetary explorations, Voyager 1 and its
twin, Voyager 2, are studying the environment of space in the
outer solar system. 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 heliopause.
The
heliosphere results from the Sun 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 magnetized 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 termination shock.
"The
data coming back from Voyager now suggest that we may pass
through the termination shock in the next three to five years,"
Stone said. "If that's the case, then one would expect that
within 10 years or so we would actually be very close to
penetrating the heliopause itself and entering into interstellar
space for the first time."
Reaching the termination shock and heliopause will be major
milestones 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 (DSN) antennas located in California,
Australia and Spain. Both spacecraft have enough electricity and
attitude control propellant to continue operating until about
2020, when electrical power produced by the RTGs will no longer
support science instrument operation. At that time, Voyager 1
will be almost 150 times farther from the Sun than the Earth --
more than 20 billion kilometers (almost 14 billion miles) away.
On
Feb. 17, Voyager 1 will be 10.4 billion kilometers (6.5 billion
miles) from Earth and is departing the Solar System at a speed
of 17.4 kilometers per second (39,000 miles per hour). At the
same time, Voyager 2 will be 8.1 billion kilometers (5.1 billion
miles) from Earth and is departing the solar system at a speed
of 15.9 kilometers per second (35,000 miles per hour).
JPL,
a division of the California Institute of Technology, manages
the Voyager Interstellar Mission for NASA's Office of Space
Science, Washington, D. C. |