You might be surprised to learn there's a way to extract enormous energy from a rapidly spinning black hole. Known as the "Penrose Process," an advanced civilization would feed material into a black hole and extract energy as some of it is hurled into space. A new paper suggests that the process could be even more efficient, cycling the material back into the black hole for another round. Or maybe this will turn into an extremely powerful bomb.

Astronomers performing a vast infrared variable star survey have discovered new additions to the stellar menagerie. These new types of stars are normally hidden by gas and dust, but infrared radiation can pierce the shroud, revealing them for the first time. They watched hundreds of millions of stars, noting 222 that showed the greatest changes in brightness. Some were protostars coming to life, and others were ancient stars shedding material in their old age.