The most lead-rich stars known to science may represent a brief stage in stellar evolution that scientists have theorized but previously haven’t seen. The small suns, known as HE 2359-2844 (artist’s representation shown) in the constellation Sculptor and HE 1256-2738 in Hydra, were among nine identified as being helium-rich in a previous survey of stars. But new analyses show that these two are doubly unusual because they also sport atmospheres with lead concentrations about 10,000 times those seen in the atmosphere of our sun, the researchers report online today in Monthly Notices of the Royal Astronomical Society. The surface temperatures of these two bluish stars are estimated to be about 38,000°C (far hotter than our sun’s surface temperature of about 5500°C), so hot that lead atoms in their atmospheres have been stripped of three electrons. The stars may be passing through a stage of stellar evolution that lasts no more than a few tens of thousands of years, the scientists say—a phase between red giants (about 30 or 40 times the size of our sun) and blue subdwarfs (stars about one-fifth the size of our sun but seven times hotter and 70 times brighter). The lead surrounding the stars—which was part of the original cloud of gas and dust from which these stars formed, not generated by reactions in the evolving stars themselves—may be dispersed within an atmospheric layer as much as 100 kilometers thick (depicted patchily in pink) that altogether weighs up to 100 billion metric tons.
A new Alaska law aims to increase transparency about medical costs and expand access to behavioral health services.Listen nowGovernor Bill Walker signed SB 105 into law yesterday. It combines three different pieces of healthcare legislation into one and requires healthcare providers to post signs letting patients know they can request estimates of medical costs in advance. Patients must receive the estimates within 10 days of asking. It also requires providers to post the costs of their most common procedures.In addition, the law allows independent, licensed marital and family counselors to bill Medicaid directly. The goal is to increase the number of behavioral health providers who will accept Medicaid patients. There’s currently a shortage of Medicaid-eligible behavioral health providers in the state.Behavioral health services include treatment for substance abuse, depression, anxiety, post-traumatic stress disorders and other mental health conditions.