Orkney's Piece of Space

From Scapa Flow to Outer Space: Orkney’s Unlikely Role in Atomic Science

What does outer space, Scapa Flow, and a corroded lump of steel have in common?

The answer lies beneath Orkney’s waters — and in the dawn of the atomic age.

The Fleet on the Seabed

On 21 June 1919, the crews of the German High Seas Fleet scuttled their own ships in Scapa Flow rather than see them divided among the victorious Allies. In a matter of hours, 52 warships — battleships, cruisers, and destroyers — slipped beneath the surface of the great natural harbour.

For years they lay rusting. At first, they were valuable only as scrap. Large-scale salvage began in the 1920s and 1930s, led by pioneering engineers such as Ernest Cox, who raised entire capital ships using techniques that were barely believable at the time.

At that stage, the ships were just steel.

The World Changes in 1945

That all changed on 16 July 1945, when the first atomic bomb was detonated at Alamogordo, New Mexico, during the Trinity test.

The physicist J. Robert Oppenheimer later recalled thinking of a line from the Bhagavad Gita:

“Now I am become Death, the destroyer of worlds.”

That explosion — followed by decades of nuclear weapons testing — released radioactive isotopes into the atmosphere. These particles spread globally and settled into soil, water, and air. From that point on, almost all newly smelted steel carried trace amounts of background radiation.

The contamination is harmless for almost all uses. But for a handful of scientific fields, “almost” was not enough.

Why Old Steel Became Precious

Some instruments must operate at levels so sensitive that even the faintest radiation interferes with results. These include:

• Low-level radiation detectors

• Medical and environmental spectrometers

• Particle physics experiments

• Early dark-matter detection equipment

As CERN physicist Carlo Rubbia once put it, background radiation is “the enemy of measurement at the lowest limits.”

Steel produced before 1945, smelted before atmospheric nuclear testing, lacks this radioactive signature. It became known as low-background steel — and it is exceptionally rare.

Suddenly, the wrecks in Scapa Flow were no longer just sunken warships. They were a resource the modern world could no longer reproduce.

Scapa Flow and the Atomic Age

For decades after the Second World War, Scapa Flow became the most famous reservoir of low-background steel on Earth.

Salvage operations continued into the 1950s, quietly supplying steel for laboratories, hospitals, and research institutions around the world. Much of this work was deliberately low-profile; the exact destinations of the steel were often not publicised.

It is widely reported — and repeated by institutions involved in radiation physics — that components made from Scapa Flow steel were used in spaceflight and satellite instrumentation, where background radiation must be minimised as much as possible. Some accounts even suggest material from the Flow found its way into equipment associated with the International Space Station, though precise documentation is scarce, as is typical with specialist materials.

What is certain is this: for nearly half a century, Orkney quietly supplied material that allowed scientists to measure the universe more accurately.

What Is Low-Background Steel?

In simple terms:

Low-background steel is steel made before nuclear weapons testing, when radioactive fallout entered the global environment. Because modern steel can contain minute traces of this contamination, older steel is still prized for use in extremely sensitive scientific and medical instruments.

Today, similar low-activity materials can be produced by carefully selecting raw materials and tightly controlling manufacturing environments — but the demand for historic steel has never entirely disappeared.

Orkney’s Hidden Legacy

Scapa Flow is often remembered for warships and wartime drama. But its later role is quieter, stranger, and in some ways more remarkable.

Steel that once formed the hulls of battleships went on to help scientists study radiation, particles, and space itself. It is a reminder that Orkney’s history doesn’t just sit in museums or on the seabed — it threads its way into modern science, medicine, and exploration.

Want to know more about the scuttling of the German fleet?

See our 74 Flags of Ludwig video for the full story behind one of Orkney’s most extraordinary moments.