Astrophile: Red giant and the exploding dwarf

Supernovaes' multiple origins (Image: Romano Corradi and the Instituto de Astrofísica de Canarias)
Once upon a time, in a faraway place, a white-bearded dwarf lived next to a red-haired giant.
Every so often the giant would belch a great wind through the land, which lifted his stray hairs into the air and plastered them all over the dwarf's small hovel. Blaming the giant for poor hygiene, the dwarf vowed revenge and set about brewing the hair into a potion, hoping that downing the draught would give him the giant's great stature.

Sure enough it worked – over time, the dwarf grew larger and sprouted red hair all over his body. But one day the excited dwarf drank so much that he exploded, killing the giant and leaving behind only a candle burning in the debris.
This cosmic fairy tale seems to be the best explanation for supernova PTF 11kx, an explosion spotted 600 million light-years away, says a team led by Benjamin Dilday at the University of California, Santa Barbara.
The researchers think that a white dwarf, the ultra-dense core of a dead sun-like star, exploded after gaining too much mass from a nearby red giant, a dying star that has puffed up to many times its original size.
Figuring out what spawned the blast is important to unlocking the mysteries of the universe, because it produced what's known as a type Ia supernova.
All stellar explosions in this class have roughly the same brightness, so astronomers have been using them as "standard candles" for measuring cosmological distances. But scientists have collected different versions of how type Ias originated, which could have implications for how accurate their measurements can get.

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