We are not alone

Within each constellation, the brightest-looking star is called Alpha, the second brightest is referred to as Beta, and so on. When it came to measuring how far away from us each star might be, the brightest star in the constellation of Centaur (“Alpha Centauri”) seemed to be the nearest to our Sun, at “only” 4.2 light years in distance.

When astronomers tried to learn more about Alpha Centauri, it was discovered that there are actually two stars operating together as a binary system, and these are known as Alpha Centauri A and (you guessed it) Alpha Centauri B. But books usually still refer to Alpha Centauri as if it were one star.

In 1915, the Scottish astronomer Robert Innes discovered another star nearby, too dim to be seen with the naked eye. When the distance was calculated, it was found to be nearer to our Sun than the Alpha Centauri stars are! So, although we can see several thousand stars with the naked eye, the nearest one is simply invisible to us. I find this quite exciting, a red dwarf star (yes, really) that is our nearest, but secret, neighbour! Its name, “Proxima” Centauri, actually means “nearest”. And yet, although this star has been known for over a hundred years, many sources still state that “Alpha Centauri is our nearest star”.

Proxima Centauri is a less massive star than our Sun, slightly older and with a lower surface temperature. And yet, this month, a new discovery has been announced. Our nearest star has a planet circling it, now named “Proxima b” (artist's impression above). This planet is at the right distance from the star to enable it to have liquid water, which is important because many scientists believe that water is essential for life to exist. The zone in which this sort of planet should exist has been nicknamed “the Goldilocks Zone” – not too hot, not too cold, but just right!

Writing before Proxima Centauri itself had even been discovered, Bahá’u’lláh said, “Every… star hath its own planets, and every planet its own creatures…” The life of a planet, and indeed of a star, stretches over billions of years, and it is perfectly possible that different planets go through different stages in the evolution of life at vastly different times. So even if “Proxima b” has had/will have life, it may not necessarily exist there now. What the discovery of “Proxima b” does do is show that the presence of planets around stars is even more of a feature than previously realised, and that theoretically inhabitable planets are also more common than was realised. Crucially, to have habitable planets, the star does not have to resemble our Sun. This hugely increases the number of stars which may support habitable planets, and therefore the chances that we are not alone.

Certain scientists are already considering new theoretical ways of speedier space travel, essential if we are to travel to the nearest star systems. While that research is under way, it would be wise to sort out conditions on our own planet, ensuring that we are in a fit state to set off to visit the neighbours! Firstly, we need to establish some sort of genuine co-ordination at the planetary level. That would be greatly assisted by the choice of a world shared language. We need to abandon the practices of various kinds of warfare, including terrorism – no other planet will want us exporting violence to their worlds. If we want to have anything positive to offer our planetary neighbours, then we need to improve our economic systems, and ensure that everyone has an acceptable standard of living, before we start trying to visit other planets! Bahá’u’lláh wrote that “All men have been created to carry forward an ever-advancing civilisation”. Let us work on overcoming the world’s immediate problems so that we can present a positive and friendly face to the neighbours.