A new planet was discovered that is similar to Earth in size and composition, meaning it has a rocky surface and an iron core. But that is where similarities end. This twin, named Kepler-78b, has an orbit so close to its parent star, that the surface is about 2,000 degrees hotter than Earth's. The planet's orbit around the star takes only 8.5 hours, instead Earth's 12 month orbit. Located 400 light years away from Earth in the constellation Cyngus, this hellish Earth shouldn't exist. For a planet only 20% larger than Earth with such a small orbit, astronomers can't figure out how it was formed.
But this star, called HD 34989 (among other alphanumeric designations) is special. For one thing, it's massive, probably 10 times the mass of our Sun. It's also incredibly luminous, shining 15,000 times brighter than the Sun. Put that in the center of our solar system, and the global warming we're experiencing now would seem like the deep freeze. Happily, it's over a thousand light years away.
When a white dwarf explodes as a type Ia supernova, its death is so bright that its light can be detected across the Universe. A new observation using the Hubble Space Telescope identified the farthest type Ia supernova yet seen, at a distance of greater than 10 billion light-years.