The spectrum of a star that should not exist

This picture shows the distribution of the light of different colours coming from the remarkable star SDSS J102915+172927 after it has been split up by the X-Shooter instrument on the ESO VLT. Different colours fall in different places in this strange picture and astronomers can use this data to find the chemical signals from different elements within the star, which show up as dark interruptions of the curved lines. The spectrum of the star appears to be triple at each wavelengths as it was split up using an integral field unit to collect as much light as possible. This ancient star has been found to have the lowest amount of elements heavier than helium of all stars yet studied. The only evidence of elements heavier than helium is two dark lines from the element calcium.