Loading ...
Sorry, an error occurred while loading the content.
 

Re: [comets-ml] C/2011 L4

Expand Messages
  • dfischer@astro.uni-bonn.de
    Just ran the comet through ssd.jpl.nasa.gov?horizons - my fave eph tool - to check the general visibility on the planet throughout April when PANSTARRS (as the
    Message 1 of 36 , Jun 8 2:58 PM
      Just ran the comet through ssd.jpl.nasa.gov?horizons - my fave eph tool -
      to check the general visibility on the planet throughout April when
      PANSTARRS (as the MPEC writes it; shouldn't that be Pan-STARRS?) should be
      brightest, +3.3 at the beginning and end, about +1 in middle of the month
      - and this according to the usually veeeery conservative JPL comet
      brightness formalism.

      50 degrees North: from April ~15 (i.e. near peak) appearing veeery low at
      dusk, situation improving slowly by April 25 (when the Moon is full but
      150 degrees away), by end of April comet some 6 degrees up in bright dusk.

      25 degrees North: in mid-April appearing in bright dusk, later in the
      month higher but no real improvement over 50 deg. North

      25 degrees South: in early April high (~20 degrees) at dusk, in the middle
      of the month ~10 degrees high at dusk (at peak time), then quickly
      disappearing.

      So in a nutshell: go to S. America, S. Africa, Australia in early April
      2013 - and just after peak brightness relocate to, gasp, Germany. Once the
      orbit stabilizes I will do a more precise analysis. But I must admit I
      haven't been as pumped since first learning about McNaught and running it
      thru Horizons in 2006 ...

      Daniel

      P.S.: When I googled for this comet an hour or so ago, half of the (few)
      web pages already discussing it were from the fringe. Given what these
      weirdos did to poor Elenin, brace for something unimaginable here.
      Imagine, a bright comet discovered with a telescope the U.S. military
      financed - and coming to Earth after that has exploded anyway in Dec. 2012
      ... :-)
    • amar sharma
      Hello Rich and all, I heard the word equatorial and that caught my attention. Rarely are equatorial residents treated with brighter comets. 2006 P1 McNaught
      Message 36 of 36 , Feb 18, 2013
        Hello Rich and all,
        I heard the word "equatorial" and that caught my attention.
        Rarely are equatorial residents treated with brighter comets. 2006 P1 McNaught was a treat for northern-ers and better later
        for southern-ers, leaving us here in a deadlock; it wasnt visible except as a bright smudge with short tail. Much later only its tail rising above the horizon (when it was down south) was visible for our location for couple days (and it was clouded when I headed out!). There have been few other instances too when we equatorials were unable to see comets due to better visibility only on the other ends.
        What you quoted "Perhaps equatorial observers will be able to follow it all the way through perihelion and give us northerners a heads up" is very interesting news, for once we at equatorial latitudes will be able to follow-up prior to others. If thats the case I will surely be doing so, granted clear skies in this bad-weathered city where I live. I reside at latitude +12 at Bangalore, India.
        I had a question from
        sometime for the experts which is similar to what you posted "Although it won't be bright enough against the twilight background it will be at its best as an evening object. Just after perihelion with the comet seen against a civil or nautical twilight background".
        Can PanSTARRS be likened to 2004 Bradfield, at its current expectation of 2nd magnitude? Would the dust tail be as bright - what is its current estimate like? Or lesser or better? Any ion tail expectations alongside, visible in twilight?

        http://komety.astrowww.pl/foto/c_2004f4/full/2004f4_2004_0424_b.jpg

        or
        http://komety.astrowww.pl/foto/c_2004f4/full/2004f4_2004_0425_h.jpg
        I
        understand the tail prospect must have been discussed earlier. However, can anyone give a round-up estimate once again? Would be interesting to know.
        Regards, Amar A. Sharma.
        --- On Sun, 17/2/13, Rich <stargazer_08121961@...> wrote:
















         









        If it can continue its present rally, it may yet attain second or even first magnitude. Perhaps equatorial observers will be able to follow it all the way through perihelion and give us northerners a heads up. Although it won't be bright enough against the twilight background to become an awesome object for the general public, L4 has some advantages. It will be at its best as an evening object, and so more convenient for most people. Light pollution may be relatively insignificant near and just after perihelion with the comet seen against a civil or nautical twilight background. And of course L4 will be great practive for ISON, which just might be the genuine article!




















        [Non-text portions of this message have been removed]
      Your message has been successfully submitted and would be delivered to recipients shortly.