We are finding that the universe is such an extraordinarily energetic place that it leaves us at a loss for superlatives.
Take the latest discovery announced on Wednesday in the journal Nature: Astronomers have uncovered a new class of objects they are calling "ultra-luminous supernovas."
But hold on. Supernovae - exploding massive stars - are the biggest bangs since the Big Bang. Their light flashes across billions of light-years like cosmic flashbulbs: it's brief and intense.
A supernova sky survey called the Palomar Transient Factory, has uncovered four of these super-duper explosions that are ten times brighter than normal supernovas, and unusually bluer. Using stellar forensics, a team of astronomers also reclassified two previously mysterious flashes in the night as belonging to the same new class of brighter-than-bright supernovas.
"Our survey is finding a new ultra-luminous supernova every two weeks," Shri Kulkarni of Caltech told Discovery News. Statistically, that means that one in every 10,000 normal supernova is, well, a super-supernova.
How does nature make an explosion that seems far more powerful than conventional supernovas that commonly arise from the implosion of a iron core inside a massive star?
Kulkarni says that nobody's quite sure, but clues come from the explosions' spectral fingerprints, captured by follow-up observations with the Keck, Hale, and William Herschel telescopes. The new supernovas are unusually blue, peaking at ultraviolet wavelengths. Even more puzzling, they take 50 days to fade away. That's much longer than the decay rate for a typical supernova.
Kulkarni says that the extra brightness is, in part, powered by huge quantities of nickel in the explosion. And this points to the progenitor star weighing in at over 100 times the mass of our sun. It manufactures enormous quantities of nickel through nucleosynthesis.
But a complete explanation for the super-brightness remains elusive. One clue may come from simply looking into the night sky. This time of year the bright red star Antares can easily be found low on the southern horizon. The star is cool but bright because it is a swollen red giant. Giants are many times our sun's diameter and have a large glowing surface area.