Feeds

Last mystery of first recorded supernova laid to rest

Turns out it's huge because it sucked

Intelligent flash storage arrays

NASA says it has put to rest any lingering doubts about the identity of the first recorded supernova, described in the Chinese historical work Book of the Later Han as having taken place in 185 A.D.

As strongly suspected by observations made by NASA's Chandra X-ray Observatory and the European Space Agency's XMM-Newton Observatory in 2006, the "guest star" sighted by Chinese astronomers 1,826 years ago is, indeed, the rather prosaically named RCW 86.

Supernova RCW 86

Data from all four space telescopes were combined to produce this image of RCW 86 (click to enlarge)

One scientist studying the supernova remnants in 2006, Jacco Vink of the University of Utrecht, said at that time: "I think it is very interesting that we can now say with some confidence, but not absolute certainty, that RCW 86 is the remnant of A.D. 185."

NASA now says that all doubt has been removed. New observations made by NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer, better know as WISE, have not only confirmed the earlier suspicions, but have determined that RCW 86 is a Type Ia supernova.

Type Ia supernovas – supernovae? – are the death throes of white-dwarf stars that have sucked enough matter from their surroundings to increase their mass to such a degree that they go thermonuclear and violently explode.

"A white dwarf is like a smoking cinder from a burnt-out fire," said astronomer Brian Williams, the lead author of the new RCW 86 study. "If you pour gasoline on it, it will explode."

Which is exactly what RCW 86 did with sufficient brilliance to be noted by unnamed Chinese observers back in 185 A.D. The actual explosion, of course, took place quite a bit longer ago than that: RCW 86 is between 8,200 and 9,100 light years away.

What caused the lingering doubt after the 2006 observations was that the remnants of the dwarf that caused RCW 86 are spread over a significantly larger area than they should be for such a recently observed explosion.

"This supernova remnant got really big, really fast," said Williams. "It's two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago."

But with the discovery that RCW 86 is a Type Ia supernova, that fast growth rate has a simple explanation: the white dwarf sucked enough dust and gas out of the way – the same dust and gas that eventually caused it go thermonuclear – that when it exploded, its guts flew into unimpeded space. ®

An earlier version of this article misstated the distance of RCW 86.

Security for virtualized datacentres

More from The Register

next story
Boffins who stare at goats: I do believe they’re SHRINKING
Alpine chamois being squashed by global warming
Comet Siding Spring revealed as flying molehill
Hiding from this space pimple isn't going to do humanity's reputation any good
Experts brand LOHAN's squeaky-clean box
Phytosanitary treatment renders Vulture 2 crate fit for export
LONG ARM of the SAUR: Brachially gifted dino bone conundrum solved
Deinocheirus mirificus was a bit of a knuckle dragger
MARS NEEDS WOMEN, claims NASA pseudo 'naut: They eat less
'Some might find this idea offensive' boffin admits
No sail: NASA spikes Sunjammer
'Solar sail' demonstrator project binned
Carry On Cosmonaut: Willful Child is a poor taste Star Trek parody
Cringeworthy, crude and crass jokes abound in Steven Erikson’s sci-fi debut
prev story

Whitepapers

Choosing cloud Backup services
Demystify how you can address your data protection needs in your small- to medium-sized business and select the best online backup service to meet your needs.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.