I WAS twelve years old when I first discovered Edward Emerson Barnard's famous work, A Photographic Atlas of Selected Regions of the Milky Way. In my continued explorations of the life of E. E. Barnard and his work, and through my personal discoveries of the cosmos, I noticed a striking set of parallels between his life and mine that made strong my devotion to his work. We were both born in December exactly 100 years apart: Barnard in 1857 and I in 1957. Barnard came from an impoverished family and grew up in civil unrest and war in America. My beginnings were much the same, and although the civil unrest was in Vietnam, it had permeated into everyday American life. At the age of nine, we both entered the workforce outside the home in an effort to financially assist our families. We both struggled through our education, always keeping a focus on our passion for astronomy. And, like Barnard, I've devoted my life to observational astronomy, with a fanaticism for the dark nebulosity within our Galaxy.

Barnard spent most of his astronomical career photographing the night sky. What he captured in those images provided greater detail than the eye could discern through the telescope. The most interesting regions found in these photographs were dark patches that Barnard called “black holes”; unique objects that are, of course, not the black holes that astronomers refer to today, but masses of dust and gas silhouetted against the brightness of the Milky Way.

This second part of the Atlas has been provided to aid in the convenient use and study of the photographs contained in Part I, for reasons which were stated in notes by Professor Barnard as follows:

When comparing astronomical photographs made with long exposures with star charts I have frequently had much trouble through the want of an approximate position, in identifying stars and other objects on the photographs. Also, very often, the colors of the stars so change their relative intensities that they are not easily recognized on the chart. The photographs in the present work are intended as pictures of the sky and it would have been impossible to mark co-ordinates on them without spoiling their pictorial value. It was therefore decided to make a map, with co-ordinates, corresponding to each photograph and on the same scale. Though this has required much work, the charts assist greatly in the approximate location of any object shown on the photographs. They have been of great service to me in studying the photographs and I believe will be a welcome addition to the Atlas.

The photographs are not all enlarged in the same proportion, and therefore are not uniform in scale. All of the fainter stars shown on the Durchmusterung charts were not put on the diagrams, but it is believed enough of them are given to permit a ready identification of objects in any part of a photograph. Four stars on each photograph, located near the corners, were identified and used for determining its scale and for locating the system of co-ordinate lines. The epoch 1875.0 was adopted and is used throughout this work.

In his article in the Astrophysical Journal for January, 1919 (49, 1-23) Professor Barnard gave a list of 182 dark objects in the sky. For the convenience of the user of this Atlas this catalogue is printed here. Three of the objects in that list have been omitted here, viz., Nos. 52, 131a, and 172, because by inadvertence the same object had been listed twice.

Mr. Barnard had begun a second list, most of the objects for which he had himself selected. Their positions were determined by Miss Calvert. It seemed best to begin the second list with No. 201; accordingly, there are no objects having the numbers from 176 to 200.

Where the space in the column for description was insufficient, a note has been added at the end of the catalogue, and this is indicated by a dagger (†) at the end of the last column.

Each dark object of the list falling within the field of a plate has been sketched in by Miss Calvert, with its number, on the corresponding chart in Part II. Where these objects have been referred to, in the descriptions of the photographs, and on the charts and in the tables, their numbers have been preceded by the letter “B.”

Introduction

Particle physics and astrophysics have much in common. Both fields build beautiful instruments to unveil hidden mysteries of space. Not only do they utilize the cutting edge (and often similar) technology to achieve best possible performance, but they also look gorgeous—shiny metal shells protecting the most precise detectors human kind ever built. We both launch big things—the astrophysicists launch things up, in the outer space; particle physicists launch things down—into enormous underground caverns where the most powerful particle accelerators collide particles to converge energy into mass and perhaps recreate the early moments of the universe. Figure 1 shows two of these spectacular launches: that of the Hubble Space Telescope and the largest part of the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC).

The more we learn about the puzzles of the world around us, the more we find an astonishing connection between phenomena happening at the largest distance scales and physics revealed at the tiniest distances we have been able to probe.

For about a quarter of a century, from 1948 to 1972, Fred Hoyle was one of the most famous astronomers in the world, renowned in the public eye not so much for his solid achievements in astrophysics as for his revolutionary ideas on the origin and nature of the universe. In Britain, Hoyle enjoyed two decades of being one of the best-known scientists in the country. His controversial ideas and the disputes they caused were often in the media. The series of events that would turn him into the world's most quoted cosmologist began during his war service.

When he decided to make a career in theoretical astronomy rather than nuclear physics, Hoyle originally gave cosmology a wide berth. He afterward claimed that, in the late 1930s, it seemed inconceivable to him that something as vast and complex as the universe could be understood on the basis of the sparse observations that had been made up to that time. By today's standards, astronomers then knew little about the universe. Edwin Hubble had shown that spiral galaxies contain stars and are very much like the Milky Way. He had discovered the relationship now known as Hubble's law: the more distant a galaxy is from the Milky Way, the faster it is moving away from us. Expansion of the universe offered a natural explanation for this link between the distances of galaxies and their speeds of recession.

Introduction

The first black hole (BH), Cygnus X−1, was identified and its mass estimated in 1972. We now know of about 40 stellar-mass black holes in x-ray binaries in the Milky Way and neighboring galaxies. The masses of 21 of these, which range from ~5−15 M⊙, have been measured by observing the dynamics of their binary companion stars (Remillard & McClintock 2006; Orosz et al. 2007). In addition, it has become clear that virtually every galaxy has a supermassive black hole with M ~ 106−1010M⊙ in its nucleus. A few dozen of these supermassive BHs have reliable mass estimates, which have been obtained via dynamical observations of stars and gas in their vicinity (Begelman 2003).

With many mass measurements now in hand, the next logical step is to measure spin.

Introduction

In the present day Universe, most (if not all) massive galaxies contain super-massive black holes (SMBHs). How did the mass of these SMBHs grow as a function of time? The correlation between the mass of SMBHs and the galaxy bulge in which they reside (Magorrian et al. 1998; Gebhardt et al. 2000; Ferrarese & Merritt 2000) suggests that the processes which govern the build up of galaxies and SMBHs are related.

Cosmic growth of black holes and galaxies

Abundant evidence indicates that the growth of a supermassive black hole is closely tied to the formation and evolution of the surrounding galaxy. The energy released from accretion onto the black hole affects star formation in the galaxy, probably limiting growth at the high- and low-mass ends and, of course, the distribution and angular momentum of matter in the galaxy governs the amount of matter accumulated by the black hole (Silk & Rees 1998; King 2005; Rovilos et al. 2007).

Introduction

Gravitational wave astronomy will open a new observational window on the universe. Since large masses concentrated in small volumes and moving at high velocities generate the strongest, and therefore most readily detectable waves, the final coalescence of blackhole binaries is expected to be one of the strongest sources. During the last century, the opening of the full electromagnetic spectrum to astronomical observation greatly expanded our understanding of the cosmos. In this new century, observations across the gravitational wave spectrum will provide a wealth of new knowledge, including accurate measurements of binary black-hole masses and spins.

The high frequency part of the gravitational wave spectrum, ~10 Hz ≲ f ≲ 103 Hz, is being opened today through the pioneering efforts of first-generation ground-based interferometers such as the Laser Interferometer Gravitational-Wave Observatory (LIGO), currently operating at design sensitivity.

On 19 august 1972, Fred Hoyle sat in his office at the Institute of Astronomy in Cambridge for the last time. His summer had been busy. A record number of academic visitors had come to the institute to benefit from summer conferences, collaborations, lectures and discussions. He had fretted to make sure the institute would be financed securely for the next five years. Just three weeks earlier, the Institute of Astronomy had been born through a merger of two astronomy departments, after the university had decided to join the historic Observatories established in 1823 with the pioneering Institute of Theoretical Astronomy founded by Hoyle in 1965. Hoyle had been the head of Theoretical Astronomy for seven years, but now he had a new boss, because the university had not chosen him as the director of the combined institute.

On a sultry afternoon with a threat of thunder in the air, staff members who were in the old Observatories, including myself, made the short walk along the path through the parklike grounds to the building that had been the Institute of Theoretical Astronomy – IoTA for short – to take their afternoon tea in the library. This wonderful Cambridge tradition gave the researchers and their students an opportunity to exchange ideas, and maybe wish a departing visitor a safe trip back to California or India. But this afternoon, Hoyle would not be joining his colleagues for tea.

During the nineteenth century, savants in England continuously improved the science of astronomy, bringing it to a high professional level by the end of Queen Victoria's reign.

In January 1820, fourteen gentlemen and scholars, one of them the future computer pioneer Charles Babbage, had founded the Royal Astronomical Society, which received its Royal Charter from King William IV in 1831. Sir William Herschel, the discoverer of Uranus, the builder of giant telescopes and the most accomplished sidereal observer of his age, became the society's first president. In 1834, the British government provided the society with suitable premises free of charge, an arrangement that continued uninterrupted until 2004. The universities of Oxford and Cambridge had important observatories from 1794 and 1823 respectively, together with endowed professorships. At Greenwich, the Royal Observatory, one of the world's oldest scientific institutions, flourished in the age of Queen Victoria, and was noted for its accurate observations of the positions of stars. In 1884, an international conference in Washington, DC, convoked by President Chester Arthur of the United States, selected Greenwich as the world's prime meridian.

By the early twentieth century, British astronomy could hold its head high: a small community of professionals at the Royal Observatories and in the ancient universities conducted world-class research. Furthermore, they encouraged the development of astronomy in the dominions of the British Empire, with the establishment of observatories in Australia, Canada and South Africa, where the practitioners still looked to Greenwich for guidance.