A Tale Of Two Stars: Early Results From The Type Ia Supernova SN2011fe (Part I)

Those watching the sky in August may have heard the news that a new star had appeared: the type Ia supernova PTF11kly (later rechristened SN2011fe) had touched off in M101, the Pinwheel Galaxy, a bare 6.4 Mpc away; close enough that for a brief period the supernova was visible to anyone with a good pair of binoculars. As the closest recent type Ia observed, astronomers were able to use it to place the first direct observational constraints on the progenitor of a type Ia supernova.

Observing the “supernova of the generation” with Keck

Observing the “supernova of the generation” with Keck

Last night, I was in the Berkeley-based remote control room of the Keck telescope watching Professor Josh Bloom and his team follow up what Bloom claims to be the “supernova of the generation.”  PTF11kly, a type Ia supernova discovered by the Palomar Transient Factory in California, is one of the earliest and closest type Ia supernovae ever observed.How did I stumble into such an important observation?  Josh invited the Berkeley first-year graduate students to watch his team remotely observe on the Keck telescope.  Even without the prospect of standing witness to scientific history in the making, the five of us were excited to watch the complex operation of Keck, the largest optical telescope in the world.  While Josh facilitated observations from a control room in Waimea, Hawaii, the rest of his team controlled the instrument from a duplicate control room at UC Berkeley.  From the windowless basement room with an array of plush carpets covering the otherwise sinister black-and-white tiled floor, the other first-year graduate students and I watched history happen.  Using the LRIS spectrographon the Keck telescope, Josh’s team obtained one of the earliest spectra of a type Ia supernova ever observed.In yesterday’s post, Kim Phifer describes how the thermonuclear explosion of a white dwarf generates a type Ia supernova and how we can use type Ia supernova to measure distances.  Historically, type Ia supernovae have been used to measure the rate of the expansion of the universe.  Precise measurements of the distances and recession velocities of type Ia supernovae resulted in the discovery that the universe is expanding at an accelerating (not decelerating) rate.  The cause of the acceleration is...