Scientists at Haverford College in Pennsylvania made the finding . The researchers used a technique called X-ray fluorescence to look for tiny changes in the structure of carbon nanotubes that are caused by an external magnetic field. These are stars left behind after larger ones use up their fuel . But why thousands of these stars are there remains a mystery .
Scientists at Haverford College in Pennsylvania made the finding . They spotted X-ray emissions consistent with thousands of white dwarfs . These are stars left behind after larger ones use up their fuel . But why thousands of these stars are there remains a mystery .