Opera 'Collision'

End of the World—and then?

By Richard Wilman

From ‘When Worlds Collide’ to ‘Collision’: End of the World—and then? The film screening of ‘When Worlds Collide’ at the Apocalyptic Cinema Open Air 2023 was the start of a collaboration with the Theater and Orchester Heidelberg. On 23 June, CAPAS was invited to accompany the opera ‘Collision' with a supporting programme. Former CAPAS-Fellow Richard Wilman and current Fellow Nikita Chiu commented on the opera 'Collision' from their viewpoints of astrophysics and space innovation and technology governance, respectively. Thereafter, they answered questions from opera director Ulrike Schumann and the audience about the probability of a cosmic end, the current state of science and the connection between science and art.

The end of the world or the entire universe in a cosmic catastrophe represents the pinnacle of apocalyptic destruction, the decisive end of humanity and possibly of everything. For centuries, humanity has contemplated this threat, with celestial phenomena playing a major role in diverse cultures and providing rich narrative material for stage and screen. In April 2024, Theater and Orchester Heidelberg premiered a new production of the comic opera ‘Zusammenstoβ’ by Ludger Vollmer, based on the 1927 libretto of Kurt Schwitters and Käte Steinitz. The plot begins with the discovery of a ‘green globe’ or comet, which an astronomer, Virmula, calculates will collide with the Earth. With a strong dose of slapstick reflecting Schwitters’ Dadaist heritage and his own offshoot artistic movement ‘Merz’, subsequent scenes depict the rising human drama—and a view from Mars—as the collision draws near, until at the last moment an error in the calculations is discovered and the cataclysm is averted.

Menschen

The libretto was inspired by the dramatic events of the 1910 approach of Comet Halley in which the Earth passed through the comet’s tail amid much public hysteria. On that occasion, the panic had been stirred up by the erroneous claim that toxic gas discovered in the comet’s tail would penetrate the Earth’s atmosphere with fatal consequences. These events were researched by my working group during my CAPAS Fellowship in 2023. Here I review their scientific background, highlighting some important Heidelberg connections, and offer a contemporary perspective on the cosmic impact threat.

 The 1910 return of Comet Halley was the first to take place in the era of modern astrophysics. Photographs of the comet were taken for the first time. Astronomical spectroscopy was used to analyse its composition, the techniques having been pioneered in Heidelberg by Bunsen and Kirchoff for their analysis of the Sun in 1859. The comet was first spotted ahead of its 1910 return in September 1909 by Heidelberg astronomer Max Wolf. Since the orbits of comets can be difficult to calculate precisely, exactly when and where in the sky it would re-appear was not certain.

Max Wolf was the founding father of modern astronomy in Heidelberg and we encounter him in the opening Overture of Zusammenstoβ. He calculated that in May 1910 the Earth would pass through the tail of the comet, in which spectroscopic analysis revealed the presence of the toxic gas cyanogen. The French astronomer Camille Flammarion had a high public profile and inadvertently incited much hysteria by his claim—a mis-reported Gedankenexperiment—that the gas would enter the Earth’s atmosphere and extinguish all life. There were other wild speculations about the consequences of such a close approach of the comet.

Although the danger was downplayed by other leading astronomers—the gas in the tail is simply too diffuse—the comet’s approach in May 1910 was still met with much trepidation; fraudsters sold ‘anti-comet’ pills and there was a rapid trade in gas masks. Some blamed it for the death of King Edward VII that same month, but another comet which appeared just before Halley, the Great Daylight Comet of January 1910, was even more spectacular. 

The frenzied public atmosphere surrounding these events in 1910 vividly demonstrates how scientific findings can become distorted and misrepresented with dramatic and dangerous consequences. This is especially the case when the science has a high public impact and is rapidly evolving, as with the astronomer Virmula’s changing calculations of the comet’s orbit, and indeed as we all witnessed when the Corona pandemic unfolded.

A contemporary perspective on the asteroid and cometary threat

Earth is being bombarded with material from space continuously- about 100 tonnes of cosmic dust and small rocks enter our atmosphere every day and burn up; those around a metre in size show up as bright fireballs and fragments can reach the ground. Collisions with larger objects are rarer but more consequential, e.g. the 20 metre object which caused significant damage in the Russian city of Chelyanbinsk in 2013. Objects up to a few hundred metres in size would produce regional devastation, especially if they hit a populated area, or cause more widespread damage via a tsunami in the event of oceanic impact. Above 1km, the effects become global as dust lifted into the atmosphere blocks sunlight, causing a global climatic cooling lasting months or years, leading to the collapse of food chains, potentially killing a significant fraction of the world’s population. Some part of humanity would likely survive such an event, expected every 100,000 years, although it would certainly be a major set-back for our civilization. Going up in size, an impactor larger than 10 km would result in a global mass extinction, as with the event which destroyed the dinosaurs 66 million years ago.

So how worried should we be? In terms of the impacts with the larger asteroids which could cause a mass extinction, not very much, as essentially all the Near-Earth Asteroids greater than 1 km in size are believed to be known. In general, such asteroids are confined to the inner Solar System; we can track their orbits and collision risks decades ahead. Within another decade or so, thanks to new telescopes, we should have found essentially all the smaller, but still potentially hazardous asteroids larger than 140 metres which could cause significant regional damage. In 2022, the NASA DART mission carried out a successful demonstration of asteroid deflection technology which could be effective against smaller objects given sufficient lead time.

Theater

Whilst asteroids can generally only be discovered and observed with telescopes and would have been essentially unknown to our ancestors, comets with their spectacular tails have been observed and feared for thousands of years. They have been interpreted as omens of apocalyptic destruction. And there is likely to be a strong scientific basis to this fear, because as well as being much more visible, the threats they pose are different from those of asteroids for several reasons.

Comet Halley is arguably the most famous comet in history. Although named after English astronomer Edmund Halley who in 1705 first deduced its 76 year orbital period, it has been observed by cultures worldwide for thousands of years. It last came around in 1986 and in 2023 it reached the half-way point between that visit and its next in 2061. 

In contrast, a new comet, never previously seen or recorded by humanity, can arrive suddenly in the inner Solar System on a highly elliptical orbit with a period of many thousands of years or longer. Comets travel much faster than typical near-Earth asteroids; they are larger, often with kilometre-sized nuclei, and could have collision warning times (from discovery to impact) of months, not years. Even the orbits of known comets can be hard to predict with the precision required to rule in or out a possible collision very far ahead, as planetary perturbations and the processes which make them highly visible via their spectacular dust tails slightly alter their orbits. There could also be a large population of extinct, very dark comets for which there would be no collision warning time at all. And even if there is no collision, a close passage of the Earth through the dusty coma of a comet could deposit a significant quantity of dust in our atmosphere, leading to a catastrophic global cooling. Faced with the imminent impact or very close approach of a new comet, humanity would be essentially powerless.

Theater

The threat from world-ending cosmic catastrophes and the spotlight they shine on individual and collective human psychology and behaviour, have, of course, continued to offer cultural inspiration. Last Summer, I gave a scientific commentary for the 1950s sci-fi film When Worlds Collide, screened as part of the CAPAS Apocalyptic Cinema series, which was in some ways the forerunner to blockbuster films of more recent times such as Deep Impact and Armageddon. A summary of the commentary was published as part of the supporting programme to the opera of Theater and Orchester Heidelberg. 

Sobering though it may be to contemplate our own (albeit unlikely) destruction in a cosmic catastrophe, my own academic interest in such threats lies mainly in how they might have shaped the environment for the development of life on Earth and planets elsewhere in the Universe on timescales of billions of years. The search for life beyond Earth, primitive or intelligent, is a hot topic in contemporary astronomy and a major discovery could well happen within our lifetimes, or even within the next few years. This would certainly be one of the greatest scientific discoveries of all time; it could be a world-ending apocalypse, or at least revolutionize our world views, but whether there would be any new angles for Hollywood or literary science fiction remains to be seen! 

Richard Wilman is an Associate Professor in the Department of Physics at Durham University, UK. He is interested in natural cosmic hazards and their threats to life on Earth and elsewhere. During his fellowship at CAPAS in 2023, he investigated the apocalyptic threat of rare but devastating cosmic hazards and the long-term (post-apocalyptic) future of life in space.