28.01.2012
I still remember very distinctly when we left Stella at the hospital on the night of the 15th December 2011.
I remember feeling light, like I weighed nothing at all.
I also very clearly remember looking up to the night sky and seeing not one star. I thought to myself and said to my husband, Stella is the only Star tonight.
The following morning we received a newspaper article from a family member. The piece was from the Daily Mail ( published in the UK ) that she had purchased that morning.
The brightest kind of supernova spotted just 11 hours after it exploded… the best for decades
Pic 1- Before and after: Pinwheel Galaxy before (left) and after (right) the supernova called SN2011fe happened - it's the bright blue dot bottom right.
It's the brightest and closest stellar explosion seen in 25 years
Supernovae are bright, so bright they can sometimes be seen with the naked eye, despite being hundreds of thousands of light years away.
Now astronomers from the Lawrence Berkeley National Laboratory in California have caught radiation from the brightest category of supernova – the type Ia – just 11 hours after it exploded.
Called SN 2011fe, it was seen in the Pinwheel Galaxy 21million light years away. Not since 1986 has a type Ia been spotte
A supernova occurs when a star dies or when a white dwarf star sucks matter from a nearby star, eventually reaches a critical point and explodes with extraordinary ferocity and brightness - the equivalent of at least 10 billion d this close to Earth.
The light from thousands of type Ia's have been studied, but until now their physics - how they detonate and what the star systems that produce them actually look like before they explode - has been educated guesswork.
suns.
A star dying is a type II, a type Ia is the latter variety and the most luminous.
Peter Nugent from the Berkeley Lab said: ‘We caught the supernova just 11 hours after it exploded, so soon that we were later able to calculate the actual moment of the explosion to within 20 minutes.’
There's a specific limit to how massive the white dwarf can grow, equal to about 1.4 times the mass of our Sun, before it can no longer support itself against gravitational collapse.
As it approaches the limit, conditions are met in the centre so that the white dwarf detonates in a colossal thermonuclear explosion, which converts the carbon and oxygen to heavier elements including nickel,’ says Nugent.
‘A shock wave rips through it and ejects the material in a bright expanding photosphere. Much of the brightness comes from the heat of the radioactive nickel as it decays to cobalt.
‘Light also comes from ejecta being heated by the shock wave, and if this runs into the companion star it can be reheated, adding to the luminosity.’
‘It only takes a few seconds for the shock wave to tear apart the star, but the debris heated in the explosion will continue to glow for several hours.
‘The bigger the star, the brighter this afterglow. Because we caught this supernova so early, and with such sensitive observations, we were able to directly constrain the size of the progenitor.’
Mark Sullivan of Oxford University said:
‘Understanding how these giant explosions create and mix materials is important because supernovae are where we get most of the elements that make up the Earth and even our own bodies - for instance, these supernovae are a major source of iron in the universe. So we are all made of bits of exploding stars.'
Their results are reported in the December 15 2011 issue of the journal Nature.
Full report at Daily Mail- Supernova Pic 2 - Light fantastic: SN 2011fe glows bright - from 21million light years away
I love this, Stella my star !
For everyone to see,
shining ever so brightly
xxx
