There is a whole lot about astronomy that is simply luck. This is why Beth likes planets. For the most part, they just don’t do anything quickly, and exceptions like earthquakes can be detected from far away; so as long as you’re looking from somewhere on the planet, you’re going to catch the action.

The sky is big. Stars and such are super tiny. This means on any given night, billions of things that go flicker or flare – or that just happen to be moving – billions of things get missed as astronomers look other places. But occasionally, we get lucky. 

The Kepler mission, which was designed to find planets around alien stars, looked at the same part of the sky night after night, week after week, just waiting for the passage of a planet in front of its star. Kepler collected way more data than is of use to planet hunters, and astronomers continue to pour through the data looking for other astronomical phenomena hiding among the orbiting planets.

In a new paper that will appear in the Monthly Notices of the Royal Astronomical Society (MNRAS), astronomers have found a massive yellow star that went from hanging out being a massive yellow star to exploding as a supernova all in front of Kepler’s cameras. Stars like this live for millions and millions of years, and the entire pre-explosion warm-up act only lasts days and had never before been seen. Now, thanks to Kepler, we have 40 days of data covering this entire event in amazing, image by image, stop-action detail. This work is led by Patrick Armstrong, who states: We’ve always missed the very, very start of a [supernova] because it is so exceedingly difficult to capture that.

Normally, we spot supernovae when they are at or near the brightest part of their explosion. This data allowed researchers to catch the timing of an early shockwave moving through the atmosphere and signaling the start of the star’s collapse and explosion. This work can be used to constrain existing supernova models and answer questions like how do stars die and what elements do different stars make? One star may not seem like a lot, but in this case, one star is the only star we’ve seen, and it will be our anchor.

More Information

Australian National University press release

“SN2017jgh – A high-cadence complete shock cooling lightcurve of a SN IIb with the Kepler telescope,” P Armstrong et al., 2021 August 3, Monthly Notices of the Royal Astronomical Society