How Far We’ve Gone

Originally published in the Informanté newspaper on Thursday, 11 May, 2017. 

From the birth of the human species in Africa 200 000 years ago, humanity started to spread, and by 1500 years ago, humanity had spread out across almost every landmass on earth, save for Antarctica. The Earth was ours. True, movement was not quite as easy as it is now, but that barrier stood but a little while longer, until 8 September 1522, when Ferdinand Magellan first circumnavigated the globe. And so, we cast our eyes upwards…

By 1610, Galileo Galilei, father of modern science, perfected his telescope, and discovered Jupiter’s moons, craters on the moon, and showed Venus had phases when viewed from Earth. But it was Sir Isaac Newton who started us on the journey outwards, with the publication of his Philosophiae Naturalis Principia Mathematica, one of the most important works in the history of science. Besides his classic laws of motion, and the law of universal gravitation – contained in the first part De motu corporum (On the motion of bodies) – the last part enabled us to venture outwards. De mundi systemate (On the system of the world) laid down the mathematical basis of planetary orbits, and formed the basis of our ability to look upwards and reliably see planetary bodies where we expect them to be. 

Yet still we were trapped on this pale blue dot in the cosmos. That stopped being the case on 16 March 1926, when Robert Goddard’s first liquid fuelled rocket launched. Soon, his work was expanded upon, and after some trouble with the Germans in Europe, we began our ascent. On 4 October 1957, Sputnik 1 was launched and the first artificial satellite broadcast its deeps from space. On 3 November 1957, this was followed with the first dog in space, Laika, aboard Sputnik 2.

But low-Earth orbit was not our mission, and we cast our nets further. On 2 January 1959 the probe Luna 1 became the first object to reach escape velocity, and exit Earth’s gravitational reach. It became the first object from earth to reach the Moon’s vicinity, and soon after, on 13 September 1959, Luna 2 became the first spacecraft to impact the Moon. 

Then on 12 April 1961, Yuri Gagarin became the first human in space. Our probes, however, soon reached much further. On 14 December 1962 Mariner 2 managed the first successful planetary flyby, coming within 35 000 km of Venus. By 16 June 1963, Valentina Tereshkova became the first woman in space. We kept going. On 14 July 1965 we received the first close-up photographs of another world – Mars, taken by Mariner 4. But the race was on to the Moon.

On 3 February 1966, Luna 9 performed the first soft landing on the Moon, and sent the first photographs from the surface of another world. By 3 April 1966, Luna 10 became the first spacecraft to orbit the Moon. Then, on 20 July 1969, Neil Armstrong in the Apollo 11 became the first human to set foot on another world. To this day, this is the furthest extent of human spaceflight. Mankind has never again ventured further from its home. 

Our space probes, however, continued on its relentless outward journey. By 2 December 1971, the Mars 3 probe landed on Mars, and sent the first signals from Mars’ surface. Then, on 15 July 1972, Pioneer 10 became the first spacecraft to leave the inner solar system, on an escape trajectory away from the Sun. On 3 December 1972, it did the first flyby of Jupiter at a mere 130 000 km.

In 1977, two remarkable spacecraft launched. On August 20, Voyager 2, and on September 5, Voyager 1 was launched. Based on the data sent back by Pioneer 10, they were hardened against radiation to make them the best outer solar system explorers yet. By 5 March 1979, Voyager 1 did its flyby of Jupiter and five of its moons. On 1 September 1979, Pioneer 11 flew by Saturn and took the first photographs of its moon Titan, where the Cassini probe is currently busy with its Grand Finale. Voyager 1 finally did the same on 12 November 1980. 

But here, the distances become vast – almost unimaginable. Only on 24 January 1986 did Voyager 2 manage the first flyby of Uranus, approaching within 82 000 km. And then on 25 August 1989 it managed to fly by Neptune, getting within 30 000 km. Until now, Voyager 2 is the only spacecraft to have visited these two far-away planets. Finally, on 14 February 1990, Voyager 1 took the first photograph of the entire Solar System, before ultimately, on 25 August 2012, becoming the first spacecraft to leave the solar system.

There are still quite a few spacecraft out there, exploring the space in between us and Voyager 1 – Cassini around Saturn, Dawn exploring the asteroid belt, Juno around Jupiter, the Mars Odyssey and Mars Reconnaissance Orbiter around Mars – directing the two still-active Martian Rovers, Opportunity and Curiosity, and New Horizons that blitzed past Pluto in 2015, but none have gone as far as Voyager 1.

Voyager 1 is currently 20.6 billion kilometres from Earth. To put that into perspective – if the Earth was resized to a ball only 1 meter in diameter and placed in Windhoek, Voyager 1 would be as far away as Durban from it. Only 2 billion km behind it is Pioneer 10, also on its way out of our solar system, 18.1 billion km from Earth, but unfortunately we’ve lost contact with it back in 2003. Voyager 2, at 17 billion km from Earth, remains in contact, with Pioneer 11 at 14.3 billion km following, but out of contact since 1995. 

So here we are. Our spacecraft slowly reaching out into the cosmos, with naught but a golden record to mark our location should anyone encounter it in the vastness of interstellar space. I suppose, if nothing else, it should be some consolation that no matter what we do here, now, at least some part of us (mechanical, true, but carrying pure human ingenuity) will keep going, to mark, as a species, how far we’ve gone.