The study used supernovae within about 400 million light years of Earth, which is a relatively small fraction of the size of the visible universe, but it is hoped that future studies will significantly improve our measurements of even more distant supernovae.
At this time of year, people often ask for my astronomical/religious opinion: "What was the Star of Bethlehem?" What was this heavenly sign that a savior, that a Messiah, that Jesus was born? Can modern science prove what this object really was?
Supernova explosions occur when the dense core of a massive star collapses to form a neutron star (a very compact object, only about 12 miles in diameter), producing copious amounts of neutrinos in the process.
It is time for the Perseid meteor shower, August's illuminating pre-dawn treat for sky gazers. The fiery streaks of dust and sand-sized bits of grit are the sparkling wake residue of comet Swift-Tuttle, last seen in northern hemisphere skies in 1992.