The nuclear waste buried far beneath the earth will be toxic for thousands of years. How do you build a warning now that can be understood in the far future?

“This place is not a place of honor,” reads the text. “No highly esteemed dead is commemorated here… nothing valued is here. What is here was dangerous and repulsive to us. This message is a warning about danger.”

In the 1950s, with the USSR seemingly sprinting ahead in the space race, US scientists hatched a bizarre plan – nuking the surface of the Moon to frighten the Soviets.

The agency opposes an amendment that prevents it from using data brokers.

"Onkalo" is a Finnish word for a cave or a hollow. It implies something big and deep: you don't know where an onkalo ends or whether it ends at all.

It's a fitting name for a huge grave made in Finland over the last 20 years. Onkalo, which lies 450m (1,500ft) deep inside the bedrock of Olkiluoto island in the southwest of the country, is the world's first permanent storage site for spent nuclear fuel.

The gently winding road to Olkiluoto is lined with pine trees stretching high up to the sky. Nature has come back to life here after five months of winter. The ground is covered by a carpet of small yellow flowers and the air is filled with birdsong. It's almost too beautiful a setting for a major industrial site.

Olkiluoto is home to three nuclear reactors, which stand side by side on the seaside. The third launched only this year, becoming the first new reactor to provide power in Western Europe in 15 years. These reactors, along with two others in Loviisa on the south coast, produce 33% of Finland's electricity.

A few minutes' drive away from the Olkiluoto reactors, construction of the world's first Geological Disposal Facility (GDF) for spent nuclear fuel is nearing completion.

In 1946, a dangerous radioactive apparatus in the Manhattan Project killed a scientist when his screwdriver slipped. To tell his story, Ben Platts-Mills pieced together what happened inside the room.

Less than a year after the Trinity atomic bomb test, a careless slip with a screwdriver cost Louis Slotin his life.

In 1946, Slotin, a nuclear physicist, was poised to leave his job at Los Alamos National Laboratories (formerly the Manhattan Project). When his successor came to visit his lab, he decided to demonstrate a potentially dangerous apparatus, called the "critical assembly". During the demo, he used his screwdriver to support a beryllium hemisphere over a plutonium core. It slipped, and the hemisphere dropped over the core, triggering a burst of radiation. He died nine days later.

Last week, BBC Future explored the consequences of this fatal accident in a specially illustrated story created by the artist and writer Ben Platts-Mills:

• The Blue Flash: How a careless slip led to a fatal accident in the Manhattan Project

In this gallery, Platts-Mills explains how he composed the illustrations, based on reconstructions created shortly after the accident, archive photographs, and his own mock-up of the apparatus built from household materials.