When Galaxies Were Born — The Quest for Cosmic Dawn
Review by Pedro Russo
Space is one of the greatest adventures in the history of humanity: an all-action, violent arena with exotic phenomena that are counter-intuitive, spectacular, mystifying, intriguing and fascinating. This book is a significant contribution to understanding the inner workings of that journey of discovery.
The late 1960s and early 1970s were periods of cultural and social “revolutions”: civil rights movement, anti-war protests, women’s rights, gay rights, environmental movements and, in many ways, a revolution in astronomy. At that time, the young astronomer Richard S. Ellis was just starting his career. He wanted to be part of this change and his curiosity led him to an exciting career in astronomy research. Here, he details the incredible journey of making sense of the early Universe, when our Universe was only at 1% of its 13.8 billion years.
Ellis’s story starts three decades before he was born. In the early 1920s, the astronomy community was still debating the nature of our Milky Way and the many nebulae we could observe in the night sky. In what was known as the Great Debate, two fields of astronomy exchanged arguments regarding the nature of these objects. One side argued that the nebulae were small objects just outside our own Milky Way, and the other side that these nebulae were large and distant galaxies. In the late 1920s, astronomers in Europe and the USA calculated the distance to the Andromeda Nebulae, proving that this was a celestial body well beyond our own galaxy. This marked the beginning of a new field of astronomy in which Ellis made his career: extragalactic astronomy.
Ellis was in the driving seat of many key research infrastructures and programmes that contributed to exciting discoveries of the last five decades concerning the earliest known galaxies in our Universe. These early galaxies are the lighthouses of a very young Universe and are essential to understanding the early physics of our Universe: a few hundred thousand years after the big bang, protons and electrons started joining to form the simplest element, hydrogen. About 150 million years later, the first stars and galaxies emerged but were surrounded by a “fog” of hydrogen gas. This gas absorbed the light emitted by these early stars.
Over the next several hundred million years, the radiation from these early stars and galaxies split the surrounding hydrogen into protons and electrons, thus clearing away the “hydrogen” fog and making the Universe transparent. This transparency now allows astronomers to observe some early galaxies directly. As he chronicles in this book, Ellis and many of his colleagues meticulously observed these early galaxies and contributed to a deep understanding of the physical properties and nature of some of the most distant objects in our Universe.
Astronomy explores some of the largest philosophical questions facing humanity: Where do we come from? Where will we end? Space is one of the greatest adventures in the history of humanity: an all-action, violent arena with exotic phenomena that are counter-intuitive, spectacular, mystifying, intriguing and fascinating. This book is a significant contribution to understanding the inner workings of that journey of discovery.
Ellis also points out some of the challenges in highlighting the importance of science communication to many leading scientists, revealing attitudes regarding science communication by the (European) research community:
After the panel’s recommendations [a US report regarding the Hubble Space Telescope and future space telescopes] were agreed, I was required to present the conclusions to senior ESA staff in Paris … An interesting section of [the] report emphasised American scientists’ strong desire for public accountability. This was contained in a sympathetically written section of the report entitled “Sharing the Adventure: Inviting the Public Along.” When I began talking about this aspect of our report during my ESA presentation, I was interrupted by the ESA director of science, Roger Bonnet […] who interjected with some frustration, “Please, Dr Ellis, spare us this aspect of your presentation! We, in Europe, do not share this curious American desire to engage the general public.”
Since that event in the mid-1990s the recognition of the importance of science communication has increased globally, also in Europe. But this account is a good reminder that science communication is never a given, and science communicators have to justify frequently their contributions to public understanding, appreciation and participation in science.
Ellis’s rich, deep and comprehensive account of the research also includes the quest to build some of the largest research infrastructures, modern telescopes such as Gemini, Keck, Hubble Space Telescope, Square Kilometre Array (SKA) or the most recent James Webb Space Telescope. Ellis navigates these Big Science projects, the political challenges, the importance of international collaborations, the many drawbacks and compromises and of course, the human nature of working together.
It would be expected that in this personal account of his career, Ellis would also include a deeper reflection on social issues in astronomy. Unfortunately, many key challenges are overlooked: the lost decades of the gender gap in astronomy (Ellis shrugs it off in his preface); the importance of re-examining history and providing the proper account and credit to researchers involved in scientific discoveries (discussed briefly as a footnote in chapter 2); the role of Pinochet’s dictatorship in Chile and land rights during the establishment of the European Southern Observatory in Chile in the late 1980s; the ongoing controversies regarding indigenous and land rights and telescopes on Mauna Kea, Hawaii; the social issues around SKA in South Africa.
The astronomy community and its leaders have not been paying enough attention to the other cultural and social revolutions in the last 50 years. They did not deliver on crucial issues of gender, social and environmental justice. We need to reflect deeply on these issues and act to recover the lost time. Kevin Govender, director of the International Astronomical Union’s Office of Astronomy for Development, has asked: “What is more important, producing new knowledge about the Universe or bringing humanity along?” Richard S. Ellis and the astronomy community have been focused on producing new knowledge and it is past time to bring humanity along.
Pedro Russo is a University Professor in Astronomy and Society at Leiden University, the Netherlands, and a member of the board of directors of Ciência Viva, the Portuguese National Agency for Scientific and Technological Culture.
