10 interesting facts about Voyagers spacecraft
Both Voyager 1 and Voyager 2 were launched in 1977 (more than 37 years ago) to explore the planets in our solar system. Since then both of them are sending us valuable information about our Solar system planets, their rings and moons. They are the pioneers of exploring unexplored places of the solar system where no one has reached before. Here are some of the interesting facts about these champion spacecraft.
1. The most distant man-made object
Voyager 1 has reached a distant point at the edge of our solar system, in a region where the outward motion of solar wind slows down as interstellar gases push against the particles. Voyager 1 is the first man made object that is leaving the solar system behind where nothing or no one has ever travelled before. It has made a history in 2012 by entering the interstellar space. As of February 2015, Voyager 1 was at a distance of 19.5 Billion Kilometers (130.5 A.U.) from the Sun and Voyager 2 at a distance of 16 Billion kilometers (107 A.U.). [Note, 1 A.U.= 1 Astronomical Unit=149597871 kilometres, the mean Sun-Earth distance]
2. Voyagers are carrying greetings from us (HUMANS!)
Both of the Voyager spacecrafts are carrying a 12 inch gold copper disc that contains a collection of sounds and images that represents the diversity of life on earth. It contains a total of 115 images that include DNA structure, human anatomy, fetus, diagrams of human sex organs and image of sunset with birds, and what not! It also includes natural sounds from wind, surf, birds, thunder, other animals and even the sound of kiss. It also contains music from different cultures and from different times (beginning from a language that was used six thousand years ago!) and greeting from us in 55 different languages. Believe it or not, it also includes an instruction manual. It used symbols to explain where the spacecraft come from and how the records can be played. The record was made in the hopes of communicating with any extra terrestrial life that it may encounter. Although it will be forty thousand years before the voyager spacecraft gets closer to any other planetary system; it is the furthest where any ‘message in a bottle’ have ever travelled.
3. Tour of Solar System planets
The twin Voyagers were designed so that they can explore Jupiter, Saturn and the larger moons of these gas giants and were built to last for five years. The closest approach to Jupiter happened in 1979 by both Voyager 1 and 2, while Voyager 1 came the closest to Saturn in November 1980 and Voyager 2 in August 1981. The trajectory of Voyager 1 was designed so that the spacecraft passes close to Titan, Saturn’s largest moon. After successfully completing the primary mission, NASA extended its funding to continue a flyby on to Uranus. The spacecraft have shown their efficiency by conducting successful extended mission to the two outermost giant planets, Uranus and Neptune eventually the mission was extended to explore all the giant planets, their rings and magnetic fields, 48 of their moons. Voyager 2 had the closest approach with Uranus in January 1986 and Neptune in 1989. Voyager 1 on the other hand continued to conduct studies of the interplanetary space.
4. The Interstellar mission
The Voyager missions were extended to include Voyager Interstellar mission. After Voyager 2 encountered Neptune, it went on towards south of the ecliptic plane at an angle of 48 degrees. Voyager 1 is escaping the Solar system at a speed of about 3.6 A.U. (Astronomical Unit, 1 A.U. is the distance between Sun and Earth) per year, at an angle of 35 degrees out of the ecliptic plane to the North. Voyager 1 and Voyager 2 crossed the termination shock in December 2004 and August 2007 respectively. Both Voyagers are now moving towards heliopause, the regions where the Sun’s influence end and interstellar space begins. They both continue their mission to study UV sources among the stars and the boundary between the Sun’s influence and interstellar space. Voyager 1 entered interstellar space on August 25, 2012.
5. The family portrait
After Voyager 1 spacecraft went beyond Neptune it looked back at our Solar system and snapped a ‘family portrait’ that captured Neptune, Uranus, Saturn, Earth and Venus. But a few member of the family were missing including Mars, Mercury and Pluto. Although not part of the original mission plan, the idea came from Carl Sagan who was member of the Voyager imaging team at the time. He wrote a book in 1994 named "Pale Blue Dot” referring to the image where he wrote, "That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. … There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world." This Solar System family portrait the last image taken by Voyager 1 and afterwards the cameras were turned off to save power and memory for the instruments.
6. Voyagers take long time to contact home
Voyagers send scientific information through NASA's Deep Space Network (DSN) has been in partnership with Voyager 1 and Voyager 2 since 1977. In September 2008, when Voyager 1 was 107 A.U. away from the Sun, the signal from Voyager 1 at the speed of light took roughly 15 hours to reach DSN and for Voyager 2 it took about 12 hours when it was 87 A.U. away from the Sun. DSN keeps implementing new techniques to continue communicating with Voyagers as they travel further. Due to increasing distance and weak signals from the spacecraft, large antennas and very sensitive receivers of DSN are needed to keep communicating.
7. Scientific Discoveries
Voyagers are sending us valuable scientific information about the Solar System for more than 37 years. Voyagers have made many discoveries. Because of Voyagers, we now know that Jupiter has turbulent atmosphere with hurricane like storms, Jupiter’s moon Io has 100 times volcanic activity than that of Earth some of which are erupting, Jupiter’s moon Europa may have an ocean beneath the icy crust, Titan most likely have clouds and rains of Methane; we also know about Neptune’s Great Dark Spot, the Termination shock where the supersonic solar wind slows down etc. and the list goes on. The Voyagers are still collecting data of the interstellar space and we hope to learn more from the future data we will receive.
8. Voyagers operation
Voyager 1 and 2 are called twins because they are identical spacecraft. They both contain instruments to conduct 10 different investigations. These instruments include television cameras, infrared (IR) and ultraviolet (UV) sensors, magnetometers, plasma detectors; and cosmic ray, charged-particle sensors & spacecraft radio. Since the mission of Voyagers was to travel far from the Sun they cannot use solar panels; and so they were equipped with radioisotope thermoelectric generators (RTGs). RTGs can convert the heat produced from the natural radioactive decay of plutonium into electricity to power the spacecraft instruments, computers, radio and other systems. Data from all these instruments are transmitted to Earth typically at 160 bits per second that is captured by 34 and 70-meter Deep Space Network (DSN) stations. These data are then transmitted to JPL, which are then processed and analyzed by the science teams.
9. Voyagers current location
Voyager 1 entered in the interstellar space (the region between stars) in August 2012. It has travelled farther than anything in our solar system. Right now, Voyager 2 is in the Heliosheath – Heliosheath is the outermost layer of the Heliosphere. The twin spacecraft are following different trajectories and sending us valuable information about places in the Solar System where no one has ever travelled before. But how do we know Voyager 1 is in the Interstellar space? In March 2012, a powerful solar eruption known as Coronal Mass ejection from the Sun occurred and it took about 13 months for it to travel out to the point in space where Voyager 1 was located at the time. This vibrated the plasma around Voyager 1. It was confirmed by the data received by Voyager team in 2013 from Voyager 1's plasma wave instrument. Voyager 2 is still in the Heliosheath, it has not reached the interstellar medium yet.
Watch this 2 minute video on 'Voyager reaches interstellar space' by NASA
How many more years do you think Voyagers will be functional?
10. The final destination
Voyager 1 will eventually leave the Solar System and is moving towards the constellation Ophiuchus. It will come within 1.7 light years of an obscure star in the constellation Ursa Minor in the year 40272 AD which is 38,259 years from now. Voyager 2 is escaping the solar system out of the ecliptic plane toward south and towards the constellations of Sagittarius and Pavo. It will be within 1.7 light years of a star called Ross 248 in the constellation of Andromeda in 40000 years from now. Voyager 1 and 2 are expected to continue to operate the fields and particles science instruments until about 2020. After 2025, scientific data would probably not be collected; however, Voyager could return engineering data for several more years. They will remain in the range of Deep Space Network until around 2036.
In summary, without the Voyagers we wouldn't know many things that we know now. Its amazing how Voyagers that were built back in 1977 have performed until now. They are still active, they are still sending data and we hope to learn much more from them.
So what do you think about the performance of our champion Voyagers? Tell us in the comment below.