Comments on: AAS #9: Black hole jet of doom from Cen A http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/ I am an astronomer, writer, and skeptic. I likes reality the way it is, and I aims to keep it that way. My real name is Phil Plait, and I run the Bad Astronomy blog. Wed, 25 Nov 2009 00:28:19 -0600 http://wordpress.org/?v=2.8.4 hourly 1 By: The magnetic tendrils of NGC 1275 | Bad Astronomy | Discover Magazine http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-113030 The magnetic tendrils of NGC 1275 | Bad Astronomy | Discover Magazine Wed, 20 Aug 2008 18:42:13 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-113030 [...] NGC 1275 is a weird galaxy. It’s a giant elliptical and sits at the center of the Perseus Cluster of galaxies; a kind of megalopolis of galaxies. It sports a gigantic black hole in its heart that belches out enormous bubbles of gas, which drag tendrils of cooler gas thousands of light years out from its core (yes, black holes can eject material as well as gobble it down). [...] [...] NGC 1275 is a weird galaxy. It’s a giant elliptical and sits at the center of the Perseus Cluster of galaxies; a kind of megalopolis of galaxies. It sports a gigantic black hole in its heart that belches out enormous bubbles of gas, which drag tendrils of cooler gas thousands of light years out from its core (yes, black holes can eject material as well as gobble it down). [...]

]]> By: Ed http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-62988 Ed Sun, 02 Mar 2008 17:59:23 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-62988 I wrote Peter Edmonds at Harvard and he stated thet the jet actually emanated from beyond the event horizon. Now it seems to me that if they originate past the event horizon, they are not comong from the black hole. So what's the fuss? Personally I think that someone on the other side threw a rock into the black hole, and it gained so much speed that it came out on this side! I wrote Peter Edmonds at Harvard and he stated thet the jet actually emanated from beyond the event horizon. Now it seems to me that if they originate past the event horizon, they are not comong from the black hole. So what’s the fuss? Personally I think that someone on the other side threw a rock into the black hole, and it gained so much speed that it came out on this side!

]]> By: blizno http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-62987 blizno Sat, 12 Jan 2008 02:47:13 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-62987 "On the jet. Not buying the “more or less at us” part. Look at the angular extent. It’s on the order of the size of the entire galaxy. I could make a strong case that it it pointed 45 or 50 degrees away from us. What is needed is velocities along the jet to get a handle on the pointing. But just from the morphology it looks too extended to say it is pointing “at us.” I have seen some "casual" physics on this site in other stories. Phil, I request that you use more rigor in your descriptions. Lots of your readers are layfolk who don't have any idea how to deal with the jargon you know like the backs of your own eyelids, but some of us have had training in the sciences. For those of us familiar with science and engineering, casual usage throws us off and we have to struggle to interpret your writings in real terms. I'm being picky here, but I get confused when somebody who is obviously among the top tier of scientists writes something sloppy. I understand that you're trying to make it accessible for everybody, but is there some way to work in a "double standard" where you describe the wonderful discovery in easily accessible terms and then also in scientifically rigorous terms? This isn't a criticism, it's a request. I adore your site and I visit it almost every day to read of some new, amazing observation about our glorious universe and/or to learn of the latest atrocity committed by the RR in their unpatriotic, anti-American agenda to destroy US democracy and replace it with a priesthood of their own choosing. Keep up the good work! We are counting on you. “On the jet. Not buying the “more or less at us” part. Look at the angular extent. It’s on the order of the size of the entire galaxy. I could make a strong case that it it pointed 45 or 50 degrees away from us. What is needed is velocities along the jet to get a handle on the pointing. But just from the morphology it looks too extended to say it is pointing “at us.”

I have seen some “casual” physics on this site in other stories.
Phil, I request that you use more rigor in your descriptions. Lots of your readers are layfolk who don’t have any idea how to deal with the jargon you know like the backs of your own eyelids, but some of us have had training in the sciences. For those of us familiar with science and engineering, casual usage throws us off and we have to struggle to interpret your writings in real terms.
I’m being picky here, but I get confused when somebody who is obviously among the top tier of scientists writes something sloppy. I understand that you’re trying to make it accessible for everybody, but is there some way to work in a “double standard” where you describe the wonderful discovery in easily accessible terms and then also in scientifically rigorous terms?

This isn’t a criticism, it’s a request. I adore your site and I visit it almost every day to read of some new, amazing observation about our glorious universe and/or to learn of the latest atrocity committed by the RR in their unpatriotic, anti-American agenda to destroy US democracy and replace it with a priesthood of their own choosing.
Keep up the good work! We are counting on you.

]]> By: DarkSapiens http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-62986 DarkSapiens Fri, 11 Jan 2008 17:24:51 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-62986 Hi, Phil. I sent you an e-mail a week and a half ago, requesting permission to translate some of your posts into Spanish, especially when you talk about a new image released from a telescope or a space mission, because he way you explain and relate the science behind the image and make the info so entertaining and didactical is amazing. So I thought it would be great if I could translate them to Spanish and post them in the blog of my local astronomy club: http://www.astroelche.es I would also link to the post in my personal blog. The post would include a link to your original one, and it would be said that you're the original author and I only made the translation. So well... this is one of those posts I'd like to translate. Can that be done? Hi, Phil. I sent you an e-mail a week and a half ago, requesting permission to translate some of your posts into Spanish, especially when you talk about a new image released from a telescope or a space mission, because he way you explain and relate the science behind the image and make the info so entertaining and didactical is amazing. So I thought it would be great if I could translate them to Spanish and post them in the blog of my local astronomy club:

http://www.astroelche.es

I would also link to the post in my personal blog. The post would include a link to your original one, and it would be said that you’re the original author and I only made the translation.

So well… this is one of those posts I’d like to translate. Can that be done?

]]> By: Doug http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-62985 Doug Fri, 11 Jan 2008 15:15:16 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-62985 On the jet. Not buying the "more or less at us" part. Look at the angular extent. It's on the order of the size of the entire galaxy. I could make a strong case that it it pointed 45 or 50 degrees away from us. What is needed is velocities along the jet to get a handle on the pointing. But just from the morphology it looks too extended to say it is pointing "at us." On the jet. Not buying the “more or less at us” part. Look at the angular extent. It’s on the order of the size of the entire galaxy. I could make a strong case that it it pointed 45 or 50 degrees away from us. What is needed is velocities along the jet to get a handle on the pointing. But just from the morphology it looks too extended to say it is pointing “at us.”

]]> By: Buzz Parsec http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-62984 Buzz Parsec Fri, 11 Jan 2008 04:54:49 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-62984 Doug - Yeah, if it was pointed *directly* at us, that's what it would look like, but if it's off by 10-20 degrees, we would see it as a line or as a long thin isosceles triangle pointing at the black hole. Re active vs. inactive black holes: Think of a cow quietly roaming around a pasture munching on the grass vs. the WB Tasmanian Devil on a rampage devouring everything in sight. The kicker is the cow and Taz are really the same thing; when Taz has eaten just about everything around, he turns into the cow, and if the cow gets into the cornfield, suddenly she turns into a Tasmanian Devil. Doug – Yeah, if it was pointed *directly* at us, that’s what it would look like, but if it’s off by 10-20 degrees, we would see it as a line or as a long thin isosceles triangle pointing at the black hole.

Re active vs. inactive black holes: Think of a cow quietly roaming around a pasture munching on the grass vs. the WB Tasmanian Devil on a rampage devouring everything in sight. The kicker is the cow and Taz are really the same thing; when Taz has eaten just about everything around, he turns into the cow, and if the cow gets into the cornfield, suddenly she turns into a Tasmanian Devil.

]]> By: Doug http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/comment-page-1/#comment-62982 Doug Thu, 10 Jan 2008 22:34:28 +0000 http://blogs.discovermagazine.com/badastronomy/2008/01/09/aas-9-black-hole-jet-of-doom-from-cen-a/#comment-62982 Ok, I'm confused and I'm supposed to know this stuff. If the jet is pointed "more or less at us," why does it appear to have an angular extent? Shouldn't it be a compact point with a whopping blue shift ? Ok, I’m confused and I’m supposed to know this stuff. If the jet is pointed “more or less at us,” why does it appear to have an angular extent? Shouldn’t it be a compact point with a whopping blue shift ?

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