Quasar hunting

Well, actually this one is a blazer (though I haven't the foggiest what the difference is). Anyway, it's a fairly easy target in a telescope, and even shows a bit of extent in the 16".

From my log-book:

Mrk421 3/1/2009 23:45UT; Pickering 6, NELM 6, SQM 20.7
16" Mak

The Hubble guide star catalog lists three stars nearly on top of Mrk421 (Mv 11.7, 12.1 and 12., but the Aladin previewer shows only the blazar and a companion galaxy (which is perhaps feeding it).

While trying to reduce the glare from the bright field stars I tried several low-glass-count eyepieces as well. The Pentax SMC orthos were the champs (beating even the Astro-Physics SPLs), but the difference between them and the high-glass-count Tele Vue T4s was very slight. The Meade series 4000 UWAs were perhaps a step behind the T4s, but this difference was even smaller, and may have been due to the shorter focal lengths and higher magnifications involved. All 4 designs had well-controlled glare with one of the bright field stars right on the fieldstop, althogh it was quite difficult to view right at the edge of the 8.8 UWA (a trait not shared by its even shorter sibling).

The blazar itself never quite focuses as tightly as other stars, although the distinction is small even at 600x. Still, it was enough to suspect an extended target. I got occasional hints of knots, but I could never nail down an orientation suggesting the seeing more than the companion galaxy.

Direct vision stars in the field down to Mv 14.6, with an averted vision star at 15.6.

And my sketch:



There's also a really cool close-up image of this one which shows the companion galaxy I spoke of: seds.org/~spider/spider/Misc/mrk421.html

Cheers,
-- Jeff

Interesting stuff Jeff.
I also like your eyepiece comparison report there.

In terms of the blazer...
From Wikipedia:

A type of galaxy with immense energy output in the form of high energy radiation. These are one of the most energetic entities in the universe and are powered by supermassive black holes. Blazers are now known to be quasar galaxies in which one of their two oppositely directed, relatively narrow beams of energy/particles is pointed toward Earth, which makes it seem more powerful than most other quasars that point their beams elsewhere.

Michael.

Ahh... so it's just an "advantageously oriented" quasar. Cool!

How Far away is this Blazar Jeff?

This one's actually pretty close (as far as quasars go), at about 400 million light years.

If you want to go for real distance, try 3C66A (at 4.5 billion light years) or APM08279+5255 (at about 12 billion light years). But they're also considerably dimmer at Mv 15 and 15.2.

Those two should be about at the limit of my equipment, so I wanted to bag a few easier ones first....

Cheers,
-- Jeff.

jeyjey wrote:

Well, actually this one is a blazer (though I haven't the foggiest what the difference is). Anyway, it's a fairly easy target in a telescope, and even shows a bit of extent in the 16".

Hi Jeff,

Blazars: www.perseus.gr/Astro-DSO-Quasars-Blazars.htm
Quasars: www.perseus.gr/Astro-DSO-Quasars.htm

I find these targets fascinating for various reasons such as their dimness, gravitational lensing examples, the relativistic jets from the blazars themselves etc.