M82 stifles a cosmic belch

By Phil Plait | May 27, 2009 12:01 am

M82 is a weird galaxy. Deep images of it show vast amounts of gas obviously screaming out from it, as if the galaxy itself is exploding. For a long time it was thought that exploding stars were driving the gas out of the galaxy, but now we know that M82 is a starburst galaxy, where huge numbers of stars are being born. There are so many young, hot, massive stars being made that their fierce stellar winds are driving out the material seen.

But those kinds of stars are exactly the types that live short furious lives, dying after only a few million years in titanic supernovae explosions. And now, astronomers are reporting that one has been seen… but the thing is, it can’t be seen.

Uh, say what?

SN 2008iz in M82
SN2008iz in M82. Embiggen by clicking.

OK, here’s the deal. Newly formed stars produce a lot of dust, complex molecules that are really good at absorbing visible light. M82 is lousy with new stars, so it’s choked with that dust, which blocks the visible light coming from the galaxy’s heart. However, infrared and radio light can go right through the dust. So the newly discovered supernova was seen using radio telescopes; it’s completely invisible in visible light. M82 is close, only 12 million light years away; if it weren’t for all that dust the supernova would have been visible in binoculars!

The supernova, called SN2008iz, was only just discovered. It was seen in some older data from last year, but is not seen in data taken before then. The size of the object — 20 light days, about 500 billion km, or very roughly 50 times the size of our solar system — is pretty good evidence of it being the expanding debris from an exploding star, and the circular shape is also pretty conclusive; that’s just what you expect from an expanding shell of gas.

By combining the power of several radio telescopes, astronomers can see this object in some detail, even though from our distance it looks very small. Better yet, as the debris grows larger we can watch it expand, giving information on the energy of the explosion and what sort of material surrounds it as well, just as we did for a supernova that happened in 1987.

Supernovae create the heavy elements in the Universe, including iron and calcium which are in our bones and blood. I think that’s enough to make them worthy of study all by itself… but they are also just so freakin’ cool. Unimaginably, impossibly violent explosions due to a star ending its life not with a whimper but with a bang that can outshine entire galaxies… and even that mighty light can be hidden, shrouded by the expulsions of stars just being born.

I’d say it’s ironic, but since iron is actually involved that seems somehow wrong. Still. It’s cool. And that’s ironic too.

CATEGORIZED UNDER: Astronomy, Cool stuff, Pretty pictures

Comments (43)

  1. davidlpf

    First link does seems not to work.

  2. Flying sardines

    Awesome news! 8)

    Mind you, using the word “belch” does not seem to do any supernova justice!

    A few qu :

    1) I presume its a type II core collapse supernovae right? Has this been confirmed?

    2) Any idea on the nature of the precursor star? Red Supergiant? White dwarf? Blue supergiant? Wolf-Rayet Star?

    3) I understand M82 (a.k.a. “the cigar galaxy” I think ..) is a Starburst type galaxy perhaps because its interacting with the nearby spiral M81, right?

    4) Are the two (M81 & M82) going to merge? Or in the process of doing so?

    5) Also on the checking off from top of my head to the post here – M82 and M81 are in Ursa Major, right?

    (As an Aussie I’m wishing I’m wrong & their not. Then again we’ve got the Magellanic Clouds and Eta Carinae year round – & you can’t beat that! ;-) )

    I’d say it’s ironic, but since iron is actually involved that seems somehow wrong. Still. It’s cool. And that’s ironic too.

    Well, yeah, given that the temperatures involved are … umm .. astronomical! ;-)

    BTW. @ IVAN3MAN : Thanks! :-) (In case you didn’t see on the other thread.)

  3. chris

    12 million light years is close now?

  4. IVAN3MAN

    Try this link: An Exploding Star In An “Exploding” Galaxy

    @ Flying Sardines,

    You’re welcome! :-)

  5. Spectroscope

    A question from me -

    Is this more of a supernova remnant than supernova & is there any sign of a neutron star (pulsar or magnetar) or black hole resulting from it?

  6. davidlpf

    ahhh Ivan3man your my hero.
    edited I’ll read it the morning well later in the morning.

  7. Messier Tidy-upper

    For the Wikipedia page on M82 see :

    http://en.wikipedia.org/wiki/Messier_82

    (NB. Typing just M 82 into the search gets you the gun. ;-) )

    @ Flying sardines :

    3) Yes – M82 is also the “Cigar galaxy” ( & NCG 3034) &, yes, it is a Starburst galaxy, the archetypal one actually. It is, indeed, also interacting with M81.

    4) I’d expect they’ll eventually merge, yes … But not for a very long time. The situation there seems to me to be analogous to the Milky Way-Magellanic Clouds relationship in fact, esp. the LMC.

    5) Yes. Ursa Major, it is.

    I’ll leave your other questions to others.

  8. Flying sardines

    Thanks again IVAN3MAN for that link. :-)

  9. StevoR

    The BA wrote :

    “Unimaginably, impossibly violent explosions due to a star ending its life not with a whimper but with a bang that can outshine entire galaxies… and even that mighty light can be hidden, shrouded by the expulsions of stars just being born.

    Sorry, I’m being very pedantic here I’m afraid, but “expulsions of stars just born” – really?

    I thought that the dust in galaxies like M82 was the material from which the later generations of stars will (or may) eventually form rather than material that the youngest stars have expelled.

    Now, okay, I know that young stars such as T-Tauri and FU Orionis (& RU Lupi* for that matter! ;-) ) eject a lot of material and have strong stellar winds too. However, my impression was that most of the dark dust that shrouds this supernova (and makes up the stardust from which new stars and planets form) actually originates from previous generations of stars having been produced by previous supernovae and red giant winds.

    Not that it really matters – greta new sand write upanyway. :-)

    ——————————————————————–

    * RU Lupi (pronounced : “are you loopy!?” ;-) ) is an RW Aurigae or T-Tauri type nebular variable in Lupus. Probably, a young star still in the process of accreting material it varies irregularly from 9th to 13th magnitude and is, probably, a G5 dwarf star located (again, most likely) around 400 light-years away.

    Source : Page 1,113, Burnham, Robert Jnr., Burnham’s Celestial Handbook -Volume II : Chamaeleon Through Orion’, Dover publications, 1978.

  10. StevoR-Correcting

    D’oh, editing time ran out before I could quite finish correcting … :-(

    ” greta new sand write upanyway.” = Not that it really matters – great news and write up anyway! (My pedantry aside.) :-)

    BTW. The BA noted : “The size of the object — 20 light days, about 500 billion km, or very roughly 50 times the size of our solar system.”

    What’s that in Astronomical Units (AU) ?

  11. StevoR-Correcting

    Aha! Reading the link IVAN3MAN posted I find :

    Only three months after the explosion, the ring was already 650 times larger than Earth’s orbit around the Sun.

    Which I presume matches the 20 light days figure and means 20 light days = 650 aU.

    I also find from there :

    Radio emission can be detected only from core collapse supernovae, where the core of a massive star collapses and produces a black hole or a neutron star. It is produced when the shock wave of the explosion propagates into dense material surrounding the star, usually material that was shed from the massive progenitor star before it exploded.

    Which may answer Flying sardines #2 question 1).

    Although … why wouldn’t a type I (a, b or c) supernova shockwave also produce this radio emission? Anyone know?

    Still if true, that does narrow things down for FS’es question 2 – “Any idea on the nature of the precursor star? Red Supergiant? White dwarf? Blue supergiant? Wolf-Rayet Star?”

    A type II core-collapse supernovae would have to be from either a red or blue supergiant.

    White dwarf type precursor is definitely ruled out while Wolf Rayet stars (spectral class W) also produce core-collapse supernovae – type Ic? – but with a different chemical and lightcurve variety as they’ve lost most of their outer hydrogen layers.

    As for Flying Sardines other questions :

    3) M82 interacting hence starburst?
    A. I think so

    4) M82 merging w M81?
    A. Uh .. possibly, not sure.

    5) Located in Ursa Major?

    A. Yes. According to ‘Collins Guidse to Stars & Planets (Page 251, Ridpath & Tirion, Collins , 2007) M82 & M81 are actually located in the northernmost section of Ursa Major near the boarder with Camelopardalis & Draco – just north of Dubhe or Alpha Ursae Majoris and Muscida or Omicron UMa. M81 is 7th mag thus visible in binocs as is M 82 albeit M82 is only 1/4 as bright and half M81′s apparent size. (P.252-3, Collins Guide as above.)

  12. Read this phrase from Phil’s writeup out loud: “invisible in visible light.”

    Hee hee.

  13. StevoR-Correcting

    Aaarrggh! Curse editing time limits.

    Which I presume matches the 20 light days figure and means 20 light days = 650 aU.

    Should be 650 AU with both letters capitalised. :-(

    Also I meant to add :

    Sadly for us here in the Southern hemisphere, the far northern position of M81 & M82 does indeed place them out of sight from Australia, New Zealand /Aotearoa, Argentina, South Africa, Chile, etc … Still I’d rather have the Magellanic Clouds, Eta Carinae, Omega Centauri, 47 Tucanae, the Southern Cross, Alpha Centauri, etc .. in my skies any night! ;-)

  14. bassmanpete

    “Which I presume matches the 20 light days figure and means 20 light days = 650 aU.”

    Taking 1 AU as approximately 8 light minutes and there being 1440 minutes in a day, 8 x 650 / 1440 = 3.6 light days. Going the other way, 20 x 1440 / 8 = 3,600 AU. So I make your presumption wrong – but I was never very good at maths. Someone will no doubt point to some obvious mistake I’ve made!

  15. QUASAR

    M82 collided with M81 in the past!

  16. MarkW

    1 AU is approx 500 light seconds.
    86400 seconds in a day: 1 light day approx 173 AU
    650AU roughly 3.75 light days, 20 light days roughly 3500 AU
    Figures don’t add up…

    (ninja’d by bassmanpete)

  17. MadScientist

    Those look like wings. This reminds me of a scene from a short story – I think it was by HG Wells and it involved a winged visitor and a preacher who was an ornithologist and who enjoyed killing rare birds. The red stuff must be the splattered blood from the time the preacher shot the visitor with his shotgun.

    That’s quite an impressive image from radio telescopes – I can’t wait for the SKA to be built. :)

  18. StevoR, yes, as I understand it, the chemical components of dust are made by dying, not new, stars. However, I guess that new stars (which can have big outflows ) can reprocess these to make new dust, and this could be ‘dustier’ than the original form, depending on grain size and shape, precise chemical composition, etc.

  19. Looks like my nickname for M82: “The Exploding Cigar Galaxy” is holding up just fine.

  20. Darrin

    Dang. Upon reading the title, I was hoping for an image of a .50cal rifle shooting a galaxy.
    Alas, I was sadly mistaken.
    :P

  21. Austin L

    @BA
    I was under the impression that both iron and nickel have stable isotopes that can be synthesized in the fusion reactions in stars, and that only elements heavier than nickel require a supernova.

  22. Torbjörn Larsson, OM

    Speaking of iron and seeing invisible things, there is a great photo released on observing a BH with the highest resolution yet. (In to twice the BH radius. Near perfect rotational symmetry.)

    Its looking on iron in X-rays, and sees the BH and test the theory by it being voraciously gulping down matter at the expected BH theory mass limit.

    Expect the PU crackpots ‘explaining’ what we see and why it isn’t a BH in 3 … 2 … 1 …

  23. Matt T

    @chris

    That’s what I was thinking. One of the coolest things about astronomy, to me, is the mind-blowing magnitudes of the numbers. You start to get immune, then every so often a line like that (“M82 is close, only 12 million light years away”) makes you think for a second about just how big 12e6 ly is… and then your brain melts.

  24. IVAN3MAN

    @ Torbjörn Larsson, OM,

    I’ve noticed that “the usual suspects” of EU/PC `theory’ have been somewhat quiet on Universe Today lately.

  25. Davidlpf

    @Ivan3man I think that has to do with the new commenting policy there.

    Also speaking of EU/PU crackpots I have go and some research.

  26. How fast is it esploding?

  27. IVAN3MAN

    @ PsyberDave,

    The ring-like structure is expanding at more than 40 million km/h* or 4% of the speed of light, typical for supernovae.

    *Source: MPIfR (via above link at #4).

  28. Torbjörn Larsson, OM

    @ IVANMAN & Davidplf:

    Nooo, my agency pattern detector thought it was because I started to visit!

    I guess I’m just a small person in a large universe then, not the center on which everything revolves. Figures.

    [Actually I started to visit because someone here notified that there were anti-scientists en masse there. My real guess is now that a sane commenting policy is rather effective.]

  29. Thank you, Ivan3Man.

  30. José

    @Austin L
    I was under the impression that both iron and nickel have stable isotopes that can be synthesized in the fusion reactions in stars, and that only elements heavier than nickel require a supernova.

    They can be synthesized, but you need supernova to scatter them throughout the universe. With no supernova, I assume they just end up collapsing into the star when it runs out of fuel.

  31. StevoR

    @ # 16. MarkW & # 14 Bassmanpete :

    1 AU is approx 500 light seconds.
    86400 seconds in a day: 1 light day approx 173 AU
    650AU roughly 3.75 light days, 20 light days roughly 3500 AU
    Figures don’t add up… (ninja’d by bassmanpete)

    Thanks. I was just going on the figure in the article linked by IVAN3MAN … and so I’m now more confused than ever! (But thanks anyway.) ;-)

    @ # 18. Vagueofgodalming : (May 27th, 2009 at 5:55 am)

    StevoR, yes, as I understand it, the chemical components of dust are made by dying, not new, stars. However, I guess that new stars (which can have big outflows ) can reprocess these to make new dust, and this could be ‘dustier’ than the original form, depending on grain size and shape, precise chemical composition, etc.

    Okay. Still thought the majority of the dust in the interstellar medium and galaxies like M82 was the stuff from which stars form NOT stuff that had been processed by the youngest stars … Would you please, care to clarify what you wrote, BA?

    @ # 21. Austin L :

    I was under the impression that both iron and nickel have stable isotopes that can be synthesized in the fusion reactions in stars, and that only elements heavier than nickel require a supernova.

    Stellar nucleosynthesis (the nuclear fusion alchemy that turns H into He, He -> C -> O -> Mag -> Ne ->Si etc .. ) stops at iron as far as I’m aware. Don’t think any nickel is created by it .. but I could be wrong.

    Once the stellar fusion process (es) hit iron it takes up more energy than it produces so creating a supernova when the stalemate between gravity and radiation pressure* ceases causing gravity to win temporarily – then lose in a big way in the outer layers whilst winning in a big way at the core!

    So most of the iron etc .. created by stellar nucleosynthesis is, I think, destroyed in the core or gets locked away as part of the neutron star or Black Hole left over. Maybe a little bit gets out … I’m not sure.

    However, this is only true for type II core collapse Supernovae (SN) as another sort sometimes called hypernovae which may occur in more massive stars (particle -antiparticle SN ?) such as Eta Carinae and may have been common in the very first generation of stars (population III) – destroys the entire star spreading its elements everywhere. This also happens in White Dwarf (accretion) Super-Novae where extra accreted material froma companion star causes runaway thermonuclear fuson in a white dwarf – again resulting in the total destruction of the star; ie. no stellar corpse locking away the elements!

    So Jose (#30), stellar nucleosyntheis can actually spread iron and many other elements from carbon & oxygen to sulphur, nitrogen and neon around the cosmos although I’m not sure of nickel

    However, elements beyond iron (proabably incl. nickel I think) are all made by the nuclear processes in the most extreme conditions of supernovae NOT at the hearts of stars.

    Except, that is, for a few trans-Uranium elements such as Americum, Einsteinium, Californium, etc .. which are NOT found naturally but only exists because of labs and scientists here on Earth!

    (Plus just possibly some alien scientists currently unknown to us! ;-) )

    —–

    * A star is the result of this stalemate between gravity pulling everything in & radiation pressure pushing everything out. I like that simple definition! ;-)

  32. StevoR

    # 28. Torbjörn Larsson, OM :

    Actually I started to visit because someone here notified that there were anti-scientists en masse there. My real guess is now that a sane commenting policy is rather effective.

    Playing devils’ advocate a bit here and honestly not entirely sure of the details of this matter but nevertheless I’ll ask :

    Do we really want to make things too exclusive and restrictive?

    Annoying and infuriating as some of the woo-advocates are, I think its good to have some of these woo-advocates around to debate & to give us the intellectual excercise and practice in tackling them and them an opportunity to see reasonable argument, what constitutes it and why their illogical and wrong arguments are … well… illogical and wrong! ;-)

    I think we should be wary of becoming little more than a mutual admiration society excluding those who disagree with us and not allowing them to express themselves. :-(

    This applies both here and I’d say also in the forum which speaking personally, I do NOT visit because I find it too narrow and restrictive in its operating rules & okay, also because of time and energy constraints.

    As long as people aren’t abusive and conducting a reasonably civil debate, I’d say let free speech and freedom of expression go and allow people to put their views and perspectives to us however silly – and then have those views challenged, discussed and examined reasonably by others. After all, isn’t that part of the beauty and advantage of the internet?

    Yes, in practice that means we have to put up with a few trolls, nuts and stoneheads, but that is a price I’m willing to pay, exasperating as it sometimes gets. I am a strong believer in Voltaires’ dictum : “I disagree with what you say but will fight to the death for your right to say it.”

    Now there are a few exceptions to this – yelling fire in a crowded building, givingaway wartime secrets that jepordaise lives, telling lie sinadvertising (& politics &religion) and falsely defaming & slandering people within limits. Isuppose also on bligs like this child safety and swearing language although really who doesn’t know swear words if they’re over say five?

    However these *are* rare exceptions and generally the principle holds so let everyone in and let everyone have their say as far as I’m concerned. Let the woo- lovers voice their nonsense and then let us explain why its nonsense alike! That’s thebest way tocounter woo and anti-science. Shine the light!

    All In My Humble Opinion Naturally. ;-)

  33. StevoR-Correcting

    Ran out of editing time so Take II for a couple of the paragraphs in # 32 for clarity :

    I am a strong believer in Voltaires’ dictum :

    “I disagree with what you say but will fight to the death for your right to say it.”

    Now there are a very few exceptions to this :

    a) yelling “fire” in a crowded building,
    b) giving away wartime secrets that genuinely jeopardise lives,
    c) telling lies in advertising (& this should ideally apply to politics & religion too!)
    &
    d) falsely defaming & slandering people within very strict limits.
    (Because slander and defamation lawsuits are a notorious tool of the dishonest powerful & wealthy against the less powerful and less wealthy and have often been used to repress freedom of speech and expression, eg. the McLibel case.)

    PlusI suppose also on blogs like this also

    e) , for child safety and work purposes banning swearing language – although, really, who doesn’t know swear words if they’re over, say five? Frankly, I think the anti-swearing bit is pointless and just makes us sound as sillyas Ned Flanders, dang-diddily-dang-it!

    However these *are* rare exceptions and generally the principle holds so let everyone in and let everyone have their say as far as I’m concerned. Let the woo- lovers voice their nonsense and then let us explain why its nonsense alike! That’s the best way to counter woo and anti-science. Shine the light on it! Let it appear – then blast it.

    One of the “arguments” woo & anti-science uses is that they are “repressed” or denied a say that they are not listened too because we are supposedly somehow “closed-minded”. This usually isn’t the case but restricting their ability to appear on blogs and forums (fora?) misleadingly makes it *look* like they have some “validity” in this regard. :-(

    Having said this, I will note again that this is all from my general principles – I’m not really sure what this is about or what the new rules are.

    Only that it sounds like a lot of people (of dubious sanity & rationality advocating some very poor ideas perhaps but people nevertheless ;-) ) who used to be able to express themselves somewhere have now been denied the opportunity to do so through some more restrictive policy. :-(

    Again, that’s just my nickels worth of opinion & all IMHON. :-)

  34. Davidlpf

    @StevoR there are reasons why the rules get restrictive and generally it is the woo-woo’s fault. Most do not want to discuss things calmly, most usually go straight to insults whether then evidence.
    There are some are polite and reasonable but these are rare. I had no idea about the electric universe into I joined the forum 4 years ago and I have learned and relearned a lot from the experience and I have become a better skeptic because of it, so for that I thank EU/PUers.

  35. StevoR-Correcting

    PS. If anyone wants to post my comment #32-33 above on the forum in question (BAUT?) please feel free to do so.

    I’m not sure if I, personally, am even able to get on there anymore … :-(

    I’m not banned from the BAUT as far as I know … although I might’ve been. (I have in the past made the odd .. umm . passionate contribution on controversial issues.) It’s just been literally years since ilast visited there and I’ve forgotten my old user name & password etc… there and youre not allowed to use more’n'one tag or moniker there. (mea culpa hereb on occasion.) Or discuss politics and religion as I understand things.

    Now since so many things have some political or religious aspect & since sometimes you have legitimate reason to use other tags (indicating purpose eg. joking/ informing /serious posts, multiple personalities, etc ..) such forum / blog dictates do seem unduly restrictive.

    In my eyes anyway. :-(

    @ Davidlpf # 34

    @StevoR there are reasons why the rules get restrictive and generally it is the woo-woo’s fault. Most do not want to discuss things calmly, most usually go straight to insults whether then evidence.

    That sucks I agree & having a ban on really blatant and extreme insults & ad hominems is fair enough. (Like swearing although that’s more iffy in my view.) Akllowinga certainamount of banteringand light-hearted stuff along thsoe line sis one thing though and insults are in case usually a signal to everyone that the insulting party has lost the argument & often the plot so … anyway, yeah.

  36. StevoR-Correcting

    Out of time a-gain … So correcting :

    @ Davidlpf # 34

    OTOH allowing a certain amount of bantering and light-hearted humerous “insulting” stuff along those lines (eg. PZ Myers Vs the BA) is another thing though and, I think, a line arguably does need to be drawn somewhere allowing such “banter insults” but preventing really nasty, mean and unpleasant attacks.

    Such really nasty insults are, in any case, usually a clear signal to everyone that the insulting party has lost the argument & often the plot so … anyway, yeah.

    Sometimes hyperbole and rhetoric are part of people’s – & even some culture’s – general style. For example, I think much cultural and political misunderstanding occurs because the traditional Arabic world -Muslim style is full of such overblown poetical /rhetorical exaggeration which isn’t to be necessarily taken literally – but sadly too often is. So style & even cultural exchange can sometimes be cramped by too narrow a set of regulations.

    Personally, I do try to follow the rules and be polite and rational, if sometimes funny or silly for FXT and do the right thing netiquette ~wise and all, and I feel (felt) the BAUT laws were (are? Even worse now?) kind of harsh and overly limiting. :-(

    That’s just another perspective to consider, BA?

    PS. Sorry all this is well off the topic here I know, but anyhow.

  37. StevoR

    Me # 35: since sometimes you have legitimate reason to use other tags (indicating purpose eg. joking/ informing /serious posts, multiple personalities, etc ..) such forum / blog dictates do seem unduly restrictive.

    Example – up until recently I’ve used ‘StevoR’ for many initial serious posts but then when I need to correct typos or other flaws in the original post I’ve adopted ‘StevoR-Correcting’ to indicate that the post is a correction on a previous one – & to break the monotony of too many posts with the same name in a row! ;-)

    With the new editing ability ( thanks again BA /Discover :-) ) I didn’t think I’d need to use that tag any more and could “retire” it … until I found myself running out of time to correct everything! ;-)

    Still off-topic, sorry …

  38. Davidlpf

    The light hearted stuff is fine and I often get into as well. Cursing I try to avoid as much as I can but once while I have let it out. But there have been a couple of posters here that did nothing but be rude in insulting and one was actually worse at Universe Today in my opinion. I have also say at times I can get a little heated as well.

  39. The rules here have not changed. My commenting policy is the same as it has been for years: don’t be a jerk. Don’t be rude, and don’t swear.

  40. Torbjörn Larsson, OM

    @ José:

    They can be synthesized, but you need supernova to scatter them throughout the universe.

    But what about the solar wind and other ejection processes? The references I saw was that “Novae and X-ray bursts” (IIRC at writing this) are thermally hot enough to let the CNO process run away (or is that “slip away” :-o ) towards iron.

    @ StevoR:

    Do we really want to make things too exclusive and restrictive?

    I wasn’t analyzing other effects.

  41. BMurray

    If there is iron in the obscuring dust we might at least claim that the supernova was ironically obscured.

  42. StevoR

    @ # 39 The BA – okay, good – glad the rules here are still the same. :-)

    What about the other forum thingy – the BAUT? Are there new rules there as I gathered and, if so, what are they?

    @ # 38. Davidlpf :
    The light hearted stuff is fine and I often get into as well. Cursing I try to avoid as much as I can but once while I have let it out. But there have been a couple of posters here that did nothing but be rude in insulting and one was actually worse at Universe Today in my opinion. I have also say at times I can get a little heated as well.

    Me too. We’re all human & we all get carried away and mess up on occassion. I think allowing a little latitude for folks is therefore a good thing… Although of course this does have its limits too.

    @ # 40. Torbjörn Larsson, OM :

    @ StevoR: “Do we really want to make things too exclusive and restrictive?”
    I wasn’t analyzing other effects.

    Huh? I don’t understand what you mean there at all. :-(

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