Prehistoric cave pigment to protect ESA's solar probe from Sun's glare
A pigment that was once daubed onto prehistoric cave paintings is set to protect ESA's Solar Orbiter mission from the Sun's close-up glare.
Burnt bone charcoal will be applied to the spacecraft's titanium heatshield using a novel technique.
Solar Orbiter, due for launch in 2017, will carry a portfolio of instruments to perform high-resolution imaging of our parent star from as close as 42 million km - a little more than a quarter of the distance to Earth.
Pierre Olivier, Solar Orbiter's safety engineer, said that the main body of the spacecraft takes cover behind a multi-layered 3.1 m by 2.4 m heatshield.
Researchers found that Irish company Enbio and its CoBlast technique, originally developed to coat titanium medical implants, could do the job of shielding the ESA's Solar Orbiter mission from the Sun's close-up glare.
John O'Donoghue, Managing Director of Enbio, said that the process works for reactive metals like titanium, aluminium and stainless steel, which possess a surface oxide layer.
He said that they spray the metal surface with abrasive material to grit-blast this layer off, but - as the CoBlast name suggests - they also include a second 'dopant' material possessing whatever characteristics are needed, and this takes the place of the oxide layer being stripped out.
The material Enbio will apply to the outermost titanium sheet of Solar Orbiter's multi-layered heatshield is called 'Solar Black' - a type of black calcium phosphate processed from burnt bone charcoal.
Burnt 'char bone' robustness is demonstrated by the immaculate appearance of the 30 000-year-old Chauvet Cave paintings in southern France - burnt bone from fires being the source of the very first black pigment.
(Posted on 13-02-2014)