The galaxy NGC 1291 is about 12 billion days older — and that ’s sure-enough . So what ’s it doing with a closed chain of new-sprung sensation around it ? In this freshly released image fromNASA ’s Spitzer Space Telescope , trapped gas at the galaxy ’s outskirts have triggered star birth .
Located 33 million light - years off in the Eridanus constellation , NGC 1291 is know as a barred wandflower because its central neighborhood is dominated by a foresightful prevention of maven — which appear as an " S ” in the blue circle in the paradigm above . ( Our galaxy has a bar too , though not as prominent . ) The stellar bar take shape ahead of time in the galax ’s story , and as it stirred textile around , stars and gas were forced into large , non - circular orbits . This created expanse where gasolene was constrict — called resonance — which trigger the formation of new wiz .
" The rest period of the galaxy is done maturing,“Kartik Sheth of the National Radio Astronomy Observatoryexplains in anews spillage . " But the outer ring is just now starting to light up with champion . "
In young , accelerator - plenteous extragalactic nebula , stellar bars drive gas toward the center , feed star constitution . But as the galaxy age , and the principal - form fuel runs out , the key regions become inactive , and wiz - formation shifts to the beetleweed ’s fringe . There , voluted density waves and sonority farm by the central measure commute accelerator pedal into stars .
In the image above , shorter - wavelength infrared light appears blue , long - wavelength light is scarlet . The ace in the extragalactic nebula ’s center ( blue ) are sometime , since most of the key neighborhood ’s gas was already used up by earlier generations of stars . The knocked out band ( red ) is the resonance arena where trapped gasoline has ignited a star topology - forming frenzy . The raw stars are heating up debris that radiate with infrared luminousness .
To well understand how astral bars influence extragalactic nebula , Sheth and confrere are dissect the structures of more than 3,000 galaxies in our local neighborhood as part of theSpitzer Survey of Stellar Structure in Galaxies , or S4G. " The bars are a natural intersection of cosmic evolution , and they are part of the galaxies ' endoskeleton,”he enjoin . “ Examining this endoskeleton for the fossilized clues to their past give us a unequaled view of their phylogeny . "
Image : NASA / JPL - Caltech
