Irish company using bone to make sunscreen for solar satellite

Picture a prehistoric cave-dweller producing crude animal drawings using charred bone. Now picture the same charred bone, but this time used to protect scientific satellites from the sun.

It may sound improbable but bone is being used in this way with technology developed by an Irish engineer.

John O'Donoghue, CEO of Enbio, has received funding worth €2 million from the European Space Agency to develop the technique and to build a space technology centre in Clonmel, Co Tipperary.

The firm has won the contract to produce heat and radiation shields used on ESA’s solar orbiter satellite, to be launched in 2017. The satellite will fly inside the orbit of Mercury, breaking the record for how close an orbiting satellite has got to the solar surface.

Effectively Enbio makes sunscreen for satellites, specialised surface treatments that help control high temperatures and block out damaging ultraviolet radiation, explains O’Donoghue.

He says these treatments rely on the use of calcium phosphate, the stuff that bone is made of. But instead of scraping a burnt bone across a surface, he uses grit fired by compressed air to scour metal surfaces and embeds a thin coating of burnt bone just two to five millionths of a metre thick.

He developed the technology while completing a masters in biomedical engineering.

“I had got interested in titanium grit-blasting and had been working in the medical device sector.”

He and four partners joined to set up the company in 2006, but their assumed market, medical device manufacturers, was not interested.

The five soon became two and things were looking bleak. “We never succeeded in getting this technology into medical devices. The biggest problem was ourselves. We had to pivot or die,” says O’Donoghue.

They decided to leave medical uses behind and look further afield.

“Joe O’Keeffe, a founding partner, had been working with ESA, and they got more and more excited as we showed them what we had. They came back and said we had solved their problem with thermal control measures for the solar orbiter mission.” What was MedBlast then became CoBlast and business took off.

“I see it as the swan from the ugly duckling. We have the new space coating centre in Clonmel and a research unit in Dublin.”

The latest ESA support, €1.5 million, effectively built the coating centre.

“We created a special programme to develop space-related capacities in the ESA member countries, including Ireland,” explains Kenza Benamar, the agency’s head of SME policy and strategic initiatives. “We always ask the primary contractor for information on companies that can contribute. This is how we discovered Enbio.”

This is not a bit part by the Irish firm just to bump up numbers.

“This is mission-critical technology that will give us a high level of thermal protection. It is a small company but they beat larger competition by reaching our very high requirements,” says Benamar.

Another ESA project follows close behind with the company also involved in the Neosat solar orbiter project, she said. “It will help them get a lot of business inside ESA and also outside ESA, hopefully.”

The company started working with burnt bone as a coating and its synthetic equivalent hydroxlapatite from the beginning.

“It was already being used in the medical devices sector but it was applied using a thermal plasma spray working at 6,000 degrees,” says O’Donoghue.

His innovation involved using room temperature grit-blasting but he also included hydroxlapatite in the mix, causing the substance to adhere strongly to the original metal surface.

This made it cheap and easy to use, but it had all the properties including the ability to survive searing temperatures and remain untouched.

“Without that coating you could not fly the satellite that close to the sun,” he says.

But the coating provides another service. It is difficult to make a coating stick to titanium or aluminium satellite components, and glues do not work well for the harsh conditions in space.

But once the coating is in place many other materials readily cling to it.

“That is the magic and is where all the potential lies,” says O’Donoghue.

Early on he had envisioned adding a non-stick Teflon layer to medical components, and given the ESA contracts this could become a possibility.

O’Donoghue sees other potential uses for tool in the electronics industry, oil exploration and the marine environment and other places where harsh conditions require shielding.

The company was surprised by its unexpected success in space, says Sinéad McGlynn, Enbio’s space programme manager. “It was not getting traction with medical devices but did with ESA. They could see the potential.”

The synthetic bone material used is also in common use.

“It is almost an everyday material. It is used in large processes such as refining sugar and bone china manufacture. Yet it was used in cave paintings, burnt bone to draw animals. It is a prehistoric pigment.”

There is huge potential in the space market, she believes.

“If we prove our process works on scientific satellites we can talk to companies launching telecommunication satellites that require five or six launches a year. Our centre in Clonmel is doing that, working on the solar orbiter project. But we are able to use our black layer as a base layer on which to apply other materials.”

With this in mind its research unit, which includes five PhD graduates, is developing white solar coatings and corrosion-resistant coatings.

Ironically applying coatings on metal surfaces might also bring the company back to medical devices. “We are looking at applying Teflon to the guide wires used for vascular stent insertion so they slide more easily,” she says.