(Phys.org)—Astronomers have identified another rare example of an extreme helium star. The star, designated GALEX J184559.8−413827 (or J1845−4138 for short), was initially classified as a faint helium-rich “hot subdwarf,” but new spectroscopic observations reveal that this star is more hydrogen-deficient than previously thought. The finding is available in a paper published June 11 on arXiv.org.