The Interstellar Beast: Voyager 1 

-written by Divyanshi Agrawal, edited by Muskan Agarwal

14,300,599,122 miles and counting from the time I wrote this blog. It should be safe to assume that many of us didn’t even make it to the end of the number. Well, that’s how far the Voyager spacecraft has travelled since its launch on 5th September 1977!

By extending their periods of mission and still sending information to us, the Voyager twins have been revolutionary in their contribution to space science. Needless to say, Voyager 1 was the first-ever human-made object to reach the seams beyond our solar system on August 25, 2012. 

Fascinated by space tech? Check out our blog on the James Webb Space Telescope here

The Voyagers were initially designed to conduct planetary expeditions and last only for 5 years due to funding issues. Therefore, the mission focussed on visiting Jupiter and Saturn only. Voyager 2 was launched first on August 20, 1977, while Voyager 1 took to space on 5th September, in the same year. Voyager 1 was put on a shorter and faster route to reach Jupiter before Voyager 2, also resulting in the discrepancy in their names with respect to the order of the launches. 

Voyager 1 discovered a thin ring around Jupiter along with its 2 moons – Thebe and Metis. Although the planet was studied before, these voyager missions served as beneficial, as scientists understood the geological and atmospheric processes of the Jovian planet. It also provided an element of surprise by observing the active volcanoes of Io! An activity common to earth was seen on another object for the first time!

Endowed with infrared and ultraviolet sensors, it found the aurora-like ultraviolet emissions of hydrogen in the atmospheres of Saturn. It also calculated the sidereal motion of the planet as 10 hours, 39 minutes and 24 seconds. 

NASA claims to have studied more than 10,000 trajectories before finalising the path with the least amount of time and propellant

 required. It was also during the time when all the 4 gas giants would come relatively close together after 175 years. They had kept Voyager 1’s path such as to deviate from the ecliptic plane, that is, away from the orbits of the planets, into the dark abyss of space.

Voyager 1 travelled upwards from the ecliptic plane towards the edge of the solar system. It was the first of the spacecrafts to pass through the heliosphere – which is the ultimate edge of our celestial system. The sun’s outer layer encompasses all the planets and is composed of electrons and plasma which extends up to a certain limit where it meets the interstellar wind. Voyager 1 crossed this region on August 25, 2012, making it the first-ever object to reach interstellar space. The wind at this point slows down from a million miles per hour to a quarter-million miles per hour. This was detected by the spacecraft as a “faint, persistent hum of interstellar gas”. 

Along with machinery and instruments, the voyager carries a golden record.

The record consists of everything which could identify Earth. It is composed of different music cultures, greetings spoken in 55 different languages and a message from the 39th US President of the time – Jimmy Carter and UN Secretary-General Waldheim. This was decided by Carl Sagan and his committee. They also made sure to include sounds of the surroundings on Earth, such as sounds of thunder, rain, surf and animals. Furthermore, it consists of 115 images encrypted in analogue form.

The vinyl is sent to reach extraterrestrial forms of life if they happen to exist. It is put in order to provide them with an insight into our life and planet here on Earth. The instructions are coded in a symbolic language, showing how the record is to be played. It also depicts the origin of the spacecraft. 

“The spacecraft will be encountered and the record played only if there are advanced space-faring civilizations in interstellar space.”- Carl Sagan

Carl Sagan explains how the contents of the vinyl will only be accessed if it reaches an advanced civilization, having the resources and knowledge to play the record.

Voyager 1 still wanders in the darkness and will continue to do so, for about 40,000 light-years before it comes within 1.6 light-years of a star in the constellation of Ophiuchus. Till then, it will study the ultraviolet sources from stars and explore interstellar space. Voyager 1 is only expected to transmit data through the year 2021. It has provided us with sufficient information throughout its journey of 44 years and counting! 

Enjoyed reading this blog? Consider reading about the Winter Hexagon