Chapter 2 - 'Librettising' Astrophysics to create The Flowering Desert
2.1 Introduction
Figure 3 Graphical display of the TRAPPIST-1 transit data. Source: Gillon, M., Triaud, A. et al. (2017)
2.2.a.i Detecting Exoplanetary Systems
These ultracool star systems are particularly valuable for astrophysicists as the transiting planets are quite visible and their light patterns are easy to pick up with a telescope. In order to measure the planets orbiting a star the telescope looks for dips in the brightness of the star. These will occur when something passes, or transits, in front of it, blocking some of the light emitted, and reducing the amount of light received by the telescope on earth. By analysing the magnitude and frequency of these dips in brightness, scientists can then make predictions about the number, size, orbital period and frequency of the planets orbiting the star. Figure 3 shows how these dips are represented graphically, and the orbits of planets that were constructed out of them. It is currently particularly easy to see the transit of planets around small and cool stars such as these Red Dwarfs. It will still be some time before we are able to accurately gain information about the planets transiting brighter stars, such as the Sun, elsewhere in our galaxy. This means that these ultracool dwarf stars are an important place to begin studying planetary formation and planetary biology in our galaxy. Amazingly three of the TRAPPIST-1 planets (e, f and g) were found to be in the habitable zone, and at the time of discovery this system was the one with the most planets in the habitable zone.
One of the main goals of the field of astrophysics is to find out if there is life elsewhere, and how common it might be. The discovery that the type of star that TRAPPIST-1a is – an ultracool M dwarf – can have a multi-planetary system, with planets within a habitable zone, has expanded the way that scientists see this search for life. It provided a shift to the paradigm that habitable planets form around G type stars such as our Sun (an anthropocentric approach) and opened up the possibility of a galaxy teeming with life (Triaud & Gillon, 2017). In a comment related to an article on the discovery Rd. Triaud offers his opinion in response to a question over the observation of Red Dwarfs by saying:
TRAPPIST-1 could have been discovered 10 years ago if anyone had dedicated some thoughts and a telescope to it. After all, TRAPPIST is a modest instrument, and several amateur astronomers have one in their backyard. (Triaud, 2017: online)
If we can understand the potential for life in these very common red dwarf systems, then we will be able to contextualise the formation of biological systems on earth and get much closer to understanding our place in the entire cosmos.
2.2 Context of the Research
In creating the libretto, it was essential to understand how to create a representation of the topic, alongside the key humanistic and philosophical themes that surround the research. This included not only researching the TRAPPIST-1 planetary system and the process to its discovery, but also understanding the scientists’ experience of their work. This whole project was developed across three main collaborative cycles which involved creation and performance. The first creative cycle involved researching the subject and working with Rd. Triaud, Daniel Blanco, Tadas Stalyga and Alexander Kaniewski to create short films (the overture, the triple study, and scene1 + mélodrame 1 + scene 2) which explored the initial performativity of the work. For this piece one of the most important moments that triggered the trajectory of the work was meeting and discussing TRAPPIST-1 and the experience of its discovery with Dr Amaury Triaud. The subsequent work had to take place mostly online due to the restrictions of the COVID-19 pandemic lockdowns, and so involved a series of online workshops, discussions, presentations and completion of small creative tasks. All work created by the team during the first cycle can be found in appendix AP 1.1-1.4. The second cycle involved working towards the first full performance in May 2022 at the Birmingham ThinkTank with Daniel Blanco Albert, Leon Trimble, Alexander Kaniewski, the performers, and students from the Birmingham School of Art (BSA). Work created during this second cycle can also be found in appendix AP 1.5. The end of the second cycle made use of audience feedback as a resource for the next stage of the work. In order to see a fuller analysis and the results of the audience feedback please see appendix AP 1.5.d. The final cycle involved working further with Leon Trimble to update the projections, and further develop the costumes with a new group of students from BSA, towards our final performance at Birmingham ThinkTank in January 2023.
During this chapter I will be referring to various excerpts from the opera. Please find a full recording of the dress rehearsal of the opera on 16th January 2023 and full libretto in section 2.5. The pdf of the programme which includes libretto and further information on the show can be found in appendix AP 1.5.c.
2.2.a The TRAPPIST-1 Planetary System
In this section, before exploring the creation of the work, I will outline some of the properties of the TRAPPIST-1 planetary system so that the reader can better understand the use of them in the creation of characters for the libretto.
The TRAPPIST-1 system is an alien and contrary landscape in comparison to our home, the Solar System. However, its beauty and symmetry has made it very attractive to artists, as can be seen by the number of collaborations made with artists by Rd. Triaud on his website trappist.one (2019). It is one of the flattest systems ever documented, and the planets all orbit the star in a harmonic resonance. This means their orbital periods (the time it takes each planet to rotate the star once) can be described in a series of ratios that relate to one another. They do also have some minor perturbations among them, as the planets are so close to each other that the gravitational field of each one has the potential to affect the orbit of those around it. This harmonic resonance would allow for the system to be converted into a musical form with an audible pattern, resonance or sensation.
The familiar, life-giving, star at the centre of our system, the Sun, is a G-type main sequence star, also often called a yellow dwarf. This category of star makes up roughly 7.7% of all the stars in our galaxy (Lada, 2006). It is by no means a large star, with the biggest red supergiants being measured to have a radius of up to 2,150 times the Sun’s (Fok et al., 2012), however it is among the brightest, being brighter than roughly 85% of the stars in the Milky Way. Part of the reason for this is that the most common type of stars in our galaxy, the M and then K types, are also the least bright stars. The star at the centre of the TRAPPIST-1 system, called TRAPPIST-1a, is an M type star, also known as a red dwarf (Gillon et al., 2016). This type of star makes up roughly 79% of all stars in our galaxy. Its mass is approximately 9% that of the sun and its radius just larger than Jupiter’s. It is particularly cool, even among other red dwarf stars, and is considered to be an ultracool red dwarf. It is in fact the coldest known star to host planets (from 2022) and is estimated to be 7.6±2.2 billion years old, in comparison to our Sun’s 4.6 billion years (Burgasser & Mamajek, 2017) (Delrez et al., 2022). Its full life expectancy is a very impressive 10 trillion years, whereas our Sun is only expected to be in the stable main sequence part of its life for another 10 billion years (Gesicki et al., 2018).
The artwork in figure 2 shows, through a comparison with Jupiter and some of its moons, the proximity of the TRAPPIST-1a star to its 7 Earth-sized orbiting planets. We can see from this image that the two systems are comparable, with the TRAPPIST-1a star being just slightly larger than Jupiter itself.