Quasars up close
David Whysong wrote:
Sorry to chime in late, but I haven't been monitoring SAA regularly.
Martin Brown wrote:
In message m,
Jeremiah J. Burton writes
What would a quasar look like up close?
3C273 and M87 are about as good targets as any to give a rough idea.
M87 isn't a quasar at all, it's a nonthermal radio galaxy. In any case,
Sag A* (the black hole at the center of our Galaxy) isn't huge as such
things go, and if it were more active it would probably appear as a type
2 Seyfert rather than an obscured quasar.
Mind you, M87 might make a tolerable blazar is seen from about 40 degrees
away in the right direction. Trying to fit the jet structure gives
a cool example of relativistic effects; planar objects (shocks, for example)
moving outward with a relativistic flow wil look more edge-on than they
really (i.e. geometrically) are, since the back side is seen at an earlier
stage in the flow. This may have once been called a Lorentz rotation.
Quasars is sometimes reserved for radio loud quasi-stellar objects.
Right, and AFAIK there is only 1 known radio-loud active galaxy with a
spiral host. There is also an optical luminosity cutoff for quasars.
You rang? Gotta add the new Chandra results one of these days.
Sad to say, I just learned that Mike Ledlow, who played a big
part in work on the radio-loud spiral 0313-192, died suddenly
this week in Colorado. Kinda makes me forget that pesky appendectomy
last week.
Bill Keel
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