There's a reason you never see scientists at fireworks displays - theuniverse puts on a far better show for them all year round. One suchultra-impressive artifact is "The Arches", megascale ribbons of hotplasma flowing around the supermassive black hole at the core of ourgalaxy.
The Arches might sound like the name of a detached cottage - but ifanybody does live here, it's Zeus's big brother. The name comes fromtheir distinctive shape, which work at the California Institute ofTechnology indicates is due to massive magnetic fields. These fieldsbecome extremely intense as matter is crushed on its way into the blackhole, and the magnetic field lines get crushed together along withthem. According to Doctor Serabyn and Professor Morris, these magneticfields channel vast streamers of hot plasma which radiate energyvisible from Earth (if you have the right equipment, and being in orbitprobably wouldn't hurt).
"Sagittarius A*" (pronounced A-star) is a much less poetic name, andseems quite insufficient considering its meant to describe one of themost immense objects known to science. One reason for the unimpressivemoniker is that scientists didn't know what it was when they first sawit, except that it was in the direction of the Sagittariusconstellation. Another reason is probably that if astronomers had todescribe it as "singularity in space and time the mass of four millionsuns and larger than the entire solar system", they wouldn't get anywork done because they'd need a break to settle down every few minutes.
The study of Sgr A*, as its friends call it, is a great example of someof the progress and problems faced by astronomy. Initially observerscouldn't even be sure that the Arches were connected to the black hole,or whether they were a "foreground object" - something that justhappened to be in the same direction. Observing an entire universefrom only one vantage point means we literally don't have anyperspective - ancient astronomers thought the entire heavens were asingle sphere with all the lights on it - and only ingenious inventionsand intelligent analyses allow us to work out what's moving and where.
And to take awesome pictures.
Posted by Luke McKinney.
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