Studying the Universe from Blackford Hill
/
Photo: Macumba, Wikimedia Commons Public Domain – Link
By Pippa Goldschmidt:
Blackford Hill is one of the seven hills of Edinburgh, situated a couple of miles due south of the city centre. The hill seems to mark a boundary of the city, on its north side are the city’s suburbs, arrays of tenement buildings as evenly spaced as any mathematical grid. To the south, the artifice of a golf course soon gives way to fields and moorland. If you travel up the main road to the top of the hill you must first pass under an ornate sandstone arch with a florid inscription and medallion so typical of Edinburgh Victorian architecture. An arch that could be a portal in a Scottish science fiction novel, acting as a gateway to an earlier time or place. Perhaps it also does so in real life, because the hill is host to one of the largest astronomical observatories in the UK, internationally renowned for research on objects in the early Universe.
So far in my life, I must have walked up and down this hill around a thousand times. Very few of these individual journeys have created their own distinct memories, other than the first one. I had been invited to an interview for a PhD place at the Observatory, and even though I had already looked at the route in an A to Z, I was not prepared for the experience of walking up a hill that becomes steeper as you approach its summit. By the time I finally reached the entrance, I was sweating profusely in my smart interview suit and already regretting my journey, my application for the PhD and the whole endeavour.
However, I was successful and spent the next four years studying at the Observatory. My project was concerned with quasars, incredibly luminous centres of galaxies. Because they emit so much light we can see them from billions of lightyears away, in fact they are the most distant objects known in the Universe. At the time I was studying them, they were comparatively rare; thousands of galaxies had been detected but only a few hundred quasars were known. My job was to find more of them, determine their distances, and try and understand how they were connected to their surroundings – both their underlying ‘host’ galaxy and the wider environment.
My experience of quasars was formed almost entirely through measuring the numbers attached to them. First, I knew them by their coordinates on the sky. Then they became redshifts, luminosities at different wavelengths and distances. I found that this tendency in the Observatory to experience physical objects through quantitative information started to spill over into the surroundings; as my studies progressed I couldn’t help transforming the hill into data such as the numbers of the houses, and the length of time it took me to reach the summit. (Seven minutes on a good day.) Studying this part of Edinburgh on an old Ordnance Survey map told me that the hill was 1/3 of a mile long. Contour lines centre on the summit like a fingerprint, the bottom of the hill corresponding to 200 feet altitude above sea level, while the Observatory is at 475 feet.
With time, the hill’s intangible aspects started to become both smaller and more precious: the coconut-almond smell of the flowering gorse bushes in summer, the jagged-tooth view of the castle and the Royal Mile to the north, and the sparkle of the sea to the north-east. The few days each spring when all the frogs in that part of Scotland travelled to the hill to mate and I couldn’t walk more than a few metres in any direction without encountering a gravity-defying tower of them. The oddity that I couldn’t actually see my destination as I walked up the hill, the road rises to meet an open area of scrub land and the Observatory is situated off to one side. The abrupt transition between that scrub land of gorse bushes and thin birch trees, and the estate of the Observatory which is boundaried by a handsome stone wall. The dichotomy between standing outside on a clear winter evening and gazing up at the anonymous stars, and studying quasars which are all invisible to the naked eye.
The distinction between the hill and its representation on the map seems straightforward; the hill itself is real rocks, soil, trees and buildings whereas the map is a symbol of the hill on paper or screen. This relationship between the two must be one-sided, the map can’t exist without the reality and many things are present on the hill that are not (yet) mapped. Yet I realised from my work at the Observatory that maps and their corresponding realities are not so easily divided into two separate categories. All we can know of the Universe beyond the solar system is derived from maps. We have constructed maps of the stars in Milky Way, of surrounding galaxies in the Local Group, and of more distant galaxies. Furthermore, these maps don’t have to be of specific objects, like charting the seas on Earth we can plot diffuse gas. We can even map an entity we have not yet directly detected, such as dark matter. We can never hope to know or experience anything other than the maps, so they must always stand in for the reality. In the absence of any other knowledge, perhaps eventually they become that reality.
*
The Observatory is not the only structure on the hill, about a hundred metres from it is a radio transmission tower used by the police. In the same way that the two poles of a bar magnet oppose each other, these two structures are apparent opposites; the tower is responsible for sending out invisible waves while the Observatory’s purpose is to receive waves from the sky above. Although it does this more indirectly than it used to, its two copper-topped domes (aligned along an East-West axis) each used to house a large telescope but these have long since been mothballed; two mechanical eyes blinded by obsolescence. Many astronomers who work there either travel to telescopes in other locations with better weather and less light pollution, such as Chile or Hawaii, or – increasingly – observe remotely. Telescopes in these places are sent instructions, carry out the observations in an automated fashion and transmit the data back to the Observatory.
I was always aware of a special irony in analysing images taken of the night sky during a Scottish winter day so full of cloud and mist that the Universe seemed like nothing more than a fantastical story written in numbers and graphs.
*
The map of the hill also has an iron age fort marked on it, although I’ve never managed to find it. On the other side of the hill is an eighteenth century house called the Hermitage which stands in a grass clearing, and now functions as the headquarters of a nature reserve. The Observatory, the radio transmission tower, the Hermitage and the fort all can be seen as emblems of specific eras, reminding us that each instance of time must carry along with it earlier times.
Similarly, we tend to think of places as static and fixed, but one of the first things I learned was that the map of the Universe itself is expanding outwards with almost every galaxy moving away from each other, continuously adjusting their relationships with each other.
The walk at the beginning and end of each working day separated me not just physically, but also psychologically, from the rest of my life in Edinburgh. Its role as a ritual and a boundary was reinforced by the substantial wall surrounding the Observatory. All observatories are inherently not quite of their surroundings, constructed from metal and stone and grounded in the earth, their purpose is to study distant light. Walking up the hill towards the sky was a symbol of my efforts to understand what was far above me.
***
Pippa Goldschmidt lives in Frankfurt and Edinburgh. She’s the author of the novel The Falling Sky and the short story collection The Need for Better Regulation of Outer Space (both published by Freight Books). Her work has been broadcast and published in a variety of places, most recently in Litro, Mslexia, the Times Literary Supplement and on Radio 4. Website: www.pippagoldschmidt.co.uk
