One of my oldest memories growing up in Sri Lanka in the early 80s was watching Carl Sagan’s “Cosmos” television series. This is where I first learned about NASA’s Voyager 2 space probe. Launched in 1977, the spacecraft – then in the midst of its “Grand Tour” of the outer planets – captured my imagination.
With my country consumed by civil war, imagining the world through Voyager 2’s eyes provided solace and a dream of something better. I would daydream of witnessing through its eyes Jupiter’s gigantic storms and the diverse alien landscapes of its moons. In my mind’s eye, I would float just above Saturn’s rings, mountains of water-ice in the near field merging into multicoloured arcs glinting in the distant Sun. In the late 80s, as the human world passed through more turbulent history, Voyager 2 provided visions of Uranus’ numerous faint rings shepherded by small moons and Neptune’s electric-blue crescent.
Voyager 2 continued to mark milestones throughout the significant events of my life. In 1998, as I embarked on a career in astronomy, its non-essential systems were turned off.
In 2019, 42 years after launch, Voyager 2 sent its first signal from interstellar space. Sometime this decade, as its power drawn from decaying plutonium drains away, it will fall silent. In its own orbit around the Galaxy, it will probably outlast the Earth. I find this a paradoxically comforting thought.
The astrophysicist Hiranya Peiris grew up in Sri Lanka and studied at Cambridge and Princeton. She is now Professor of Astrophysics at University College London and Director of the Oskar Klein Centre for Cosmoparticle Physics in Stockholm. Specialising in cosmology, she is best known for her work on the physics of the very early Universe in the aftermath of the Big Bang.