It took just five minutes for a NASA sounding rocket to support the decennium - old theory that the solar organisation sits within a bubble of gas bring out in 10 million - year - old supernovae explosions .
background signal 0.25 keV X - ray radiationcoming from all directionsalerted astronomer to the possibility of a “ Local Bubble ” of hot gas in the late 1960s . Combined with grounds of local depletion of coolheaded gasses , the idea was deport that the hot gas was thrown off by a serial publication of supernova explosions . However , the same radiation has also been excuse as resulting from theexchange of chargebetween ions from the solar wind and achromatic gases inside the solar system .
To test the competing theories a vocalize rocket was fired to a peak of 250 kilometer where it could detect the complaint exchange befall in the interior solar system beyond the Earth ’s atmosphere . Five bit of observation revealed that heraldic bearing exchange can indeed calculate for some of the soft X - ray emission , a team top by Professor Massimiliano Galeazzi of the University of Miami cover inNature . However , that component is only 40 % . The only believable theory submit to explain the rest is the Local Bubble hypothesis .
" This is a significant find , " said Galeazzi . " [ It ] affects our understanding of the sphere of the galax close to the Dominicus , and can , therefore , be used as a foundation for succeeding models of the galaxy structure . "
The Local house of cards is a 300 sluttish year wide while encompass the solar system and many of the more familiar stars , filled ( if that is the word ) with a tightness of fifty thousand atom per cubic metre . This compares to 2.5 x 1025molecules / m3at ocean level in our atmosphere . Even for interstellar distance this is a very depleted tightness , and the atom are distinguish by being astonishingly hot — a million degrees — and contain dissimilar element from the ordinary interstellar medium .
Supernovae happen once or twice a century in a galaxy the size of our own . They can devastate their local surround , but further afield the main effect is to spread dense element that turn on the formation of planets such as our own . The sizing of the house of cards lead to the conclusion that rather than a single supernova , 10 - 20 million years ago there were around20 nearby supernovae . None were close enough to trigger a mass defunctness , but the house of cards continue to affectsolar luminosity and therefore our climateas we slip away through .
The local house of cards is not circular , having been disrupt by many other upshot , stimulate the sun to pass in and out as it move through the galaxy .
NASA explainsthe test had to be run in December , because this is when the Earth pass through the “ helium focus cone , ” a part of indifferent helium considered the strong source of charge exchange go - rays . The launching was conducted on December 12 , 2012 — which some mass might recall as the date confederacy nuts were touting as theend of the human race , or thestart of some catastrophe , claim they mostly seem keen to forget . Ah the difference between science and pseudoscience .
