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Supernova SN 2011fe (initially designated PTF 11kly) in the Pinwheel Galaxy (M101), peaking on 7/8 September 2011: photo by BJ Fulton/Las Cumbres Observatory Global Telescope Network
You wouldn't want one for a close neighbour -- at their fiercest, they can be five billion times brighter than the sun -- but supernovae, briefly capable of outshining an entire galaxy, have in the past 400 years lit up our universe. Tycho's nova or new star, recorded in 1573, was the first direct evidence that the heavens were not immutable. Kepler's supernova in 1604 was visible even by daylight. Both served as beacons to signal the scientific revolution. The latest candidate for supernova celebrity –- provisionally called PTF 11kly -- is blazing in the Pinwheel Galaxy, 21m light years away: it has already earned its place in history, if only because astronomers caught the explosion within hours of its commencement, and are now fiercely measuring every stage of its bright but brief convulsion. This is a Type 1a supernova, and such puzzling celestial fireworks have served as "standard candles" to measure the rate at which the universe is expanding: if you know exactly how bright such a star ought to be, you can make a good guess, from its dimness, at its distance. Supernovae are, so far, science's best explanation for the heavy elements: everything from helium to iron is known to have been forged from hydrogen in the thermonuclear furnaces of ordinary stars. But gold, lead or uranium require something much fiercer, and supernovae are the best candidates for such alchemy. If so, we owe these fiery monsters everything, including the fabric of the planet from which we observe them.
-- The Guardian, 8 September 2011
"The best view of this exploding star is likely to be this Wednesday or Thursday. Look for it just after evening twilight near the ‘handle’ of ‘The Plough’," said Dr Mark Sullivan of Oxford University’s Department of Physics. "Whilst it looks more or less like just another bright star, unlike its companions this supernova will soon fade away, and after a few days it will only be visible with larger telescopes."
The discovery of the supernova is particularly important because it is a type 1a supernova –- the kind used by scientists to measure the expansion of the Universe.
Dr Sullivan added: "For many people it could be a once in a lifetime chance to see a supernova of this kind blossom and then fade before their eyes; we may not see another one like it for another forty, or perhaps over a hundred, years!"
-- Oxford University Astrophysics, 7 September 2011
Pinwheel Galaxy (M101): image by NASA/ESA/Hubble Space Telescope, 28 February 2006 (NASA)
The entire universe is composed of stellar systems. In order to create them nature has only one hundred simple bodies at its disposal. Despite the prodigious profit it knows how to make from its resources, and the incalculable number of combinations these allow its fecundity, the result is necessarily a finite number, like that of the elements themselves. And in order to fill the entire expanse nature must infinitely repeat each of its original or generic combinations.
Every star, whatever it might be, thus exists in infinite number in time and space, not only in one of its aspects, but as it is found in every second of its duration, from birth until death. All the beings spread across its surface, big or little, animate or inanimate, share in this privilege of perennity.
The earth is one of these stars. Every human being is thus eternal in every second of its existence. What I write now in a cell in the fort of Taureau I wrote and will write under the same circumstances for all of eternity, on a table, with a pen, wearing clothing. And so for all.
The sun, as seen from the surface of earth through a camera lens: photo by Lykaestria, 2005
Eternity is in love with the productions of time.
-- William Blake: from Proverbs of Hell, c. 1789
Study for Portrait II (after the Life Mask of William Blake): Francis Bacon, 1955 (Tate Gallery)
