The Mystery of Voyager 1:The Most Distant Human-made Object in Space.
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The Voyager mission consist of two spacecrafts: Voyager 1 and Voyager 2. Voyager 2 was launched before voyager 1 on August 20 1977 from Florida abroad a Titan-centaur rocket. Voyager 1 was launched on September 5 1977 from Florida abroad a Titan-centaur rocket but it was send on a faster trajectory. Because of its high speed and faster trajectory, Voyager 1 overtook voyager 2 just after a few months. Voyager 1 and 2 explored all the outer planets and their moons. Data on the unique ring system and magnetic fields of planets were also collected.
The Voyager spacecrafts are the third and fourth spacecrafts to fly beyond all the outer planets in our solar system. Before the Voyager mission, Pioneer 10 and 11 were successful in escaping the gravitational attraction of the sun. But on February 17 1998, Voyager 1 passed Pioneer 10 to become the most distant man-made object in space. Voyager 1 is currently at a distance of 14.4 billion miles from the earth.
Golden Records are Phonographic records(12 Inch Gold plated copper discs) included abroad both Voyager Spacecrafts. These records contain a greeting to any form of life, should that be encountered. They also added music from different cultures and spoken greeting in 55 languages. They also contain selected natural sounds and 115 images to showcase the diversity of life and culture of the Earth.
The Mysterious Signal
On May 18th 2022 NASA announced that the Voyager 1 had been sending back mysterious data. The AACS(Altitude Articulation and Control System) of Voyager 1 controls orientation of the spacecraft by pointing its high-gain antenna towards earth which helps in making altitude maneuvers. But the data send back by AACS does not mirror what’s happening abroad the Voyager 1.All clues show that the AACS is still working but the telemetry data is invalid. The data may appear to be randomly generated or does not reflect the current state the AACS could be in.
This issue has not triggered the onboard fault detection system s, which are programmed to put the spacecraft into safe mode, where only essential operations are carried out, giving NASA engineers time to diagnose the issue. This suggests that the high-gain antenna is in the prescribed orientation with the earth. NASA will continue to monitor the signal closely to determine if the invalid data is coming from the AACS or other systems involved in producing telemetry data. Until the nature of the issue is better understood, scientists will not be able to anticipate how long the spacecraft can collect and transmit data.
It is possible that NASA may not be able to find the source of the anomaly and instead will try to adapt to it. If they do find the source they may be able to solve the issue through software changes or by using one of the redundant hardware system of the spacecraft.
It would not be the first time NASA has relied on backup hardware. In 2017 Voyager 1’s thrusters showed signs of degradation. So engineers switched to another set of thrusters that had already been used for planetary encounters. They worked despite having being unused for about 36 years. Voyager 1’s twin, Voyager 2( currently 12.9 billion miles from earth) continues to operate normally. Both Voyagers have operated longer than mission planners expected. They are the only spacecrafts to collect interstellar space data which helped in a deeper understanding of the heliosphere(region surrounding the sun and the solar system which is filled with solar magnetic fields of the solar wind).
Each spacecraft produces less power each year limiting the number of systems the spacecraft can run. NASA has switched off various sub systems in order to preserve power for various critical systems and instruments. While NASA continues to work at solving the mystery of Voyager 1, scientists will continue to utilize most of the data coming down from the spacecraft.
Voyager 1 and 2 Trajectory through the Solar System
This visualization tracks the trajectory of the Voyager 2 spacecraft through the solar system. Launched on August 20, 1977, it was one of two spacecraft sent to visit the giant planets of the outer solar system. Like Voyager 1, Voyager 2 flew by Jupiter and Saturn, but the Voyager 2 mission was extended to fly by Uranus and Neptune before being directed out of the solar system.
To fit the 40 year history of the mission into a short visualization, the pacing of time accelerates through most of the movie, starting at about 5 days per second at the beginning and speeding up to about 11 months per second after the planet flybys are past.
The termination shock and heliopause are the ‘boundaries’ created when the plasma between the stars interacts with the plasma flowing outward from the Sun. They are represented with simple grid models and oriented so their ‘nose’ is pointed in the direction (Right Ascension = 17h 24m, declination = 17 degrees south) represented by more recent measurements from other missions.