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Comet NeoWise

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  • Registered Users Posts: 3,131 ✭✭✭Rebelbrowser


    SeaBreezes wrote: »
    Pic from cork

    Great pic. Cloudless night here and can see the plough easily. Where do I look then to find the comet? Very bright star to left of the plough is presumably Venus?


  • Registered Users Posts: 7,761 ✭✭✭Pinch Flat


    Nice clear evening in Dublin 15 but cant see jack. Is it quite close to the horizon? Looking NNW


  • Registered Users Posts: 2,855 ✭✭✭Nabber


    Pinch Flat wrote: »
    Nice clear evening in Dublin 15 but cant see jack. Is it quite close to the horizon? Looking NNW

    Light pollution might be an issue


  • Registered Users Posts: 1,524 ✭✭✭SeaBreezes


    Great pic. Cloudless night here and can see the plough easily. Where do I look then to find the comet? Very bright star to left of the plough is presumably Venus?

    Below and to the right of the plough, its faint but visible to the naked eye, its the trail you will see first.


  • Registered Users Posts: 22,198 ✭✭✭✭endacl




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  • Registered Users Posts: 483 ✭✭little bess


    Yes, went to our local park In Dublin 5 and saw it before cloud cover came over here. Visible even with light pollution and without binoculars. The tail is very obvious, you won’t mistake it for a star!


  • Registered Users Posts: 14,279 ✭✭✭✭M.T. Cranium


    Great pic. Cloudless night here and can see the plough easily. Where do I look then to find the comet? Very bright star to left of the plough is presumably Venus?

    Assuming your question came shortly after your view of the sky, the bright star to the left was probably Arcturus. Jupiter would be high in the south at midnight with Saturn to its left, Venus rises around 0300h local time ahead of the Sun. Mars is also visible after 0130h and is midway between Venus and Jupiter-Saturn.


  • Registered Users Posts: 14,279 ✭✭✭✭M.T. Cranium


    Early risers (now to 0400h) can see Venus, Aldebaran and the crescent Moon in a tight conjunction rising in the east.


  • Registered Users Posts: 33,721 ✭✭✭✭RobertKK


    A friend in the Netherlands showed me this picture that his friend took.


  • Registered Users Posts: 8,219 ✭✭✭Gaoth Laidir


    RobertKK wrote: »
    A friend in the Netherlands showed me this picture that his friend took.

    How come no stars are visible in that photo?


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  • Registered Users Posts: 6,834 ✭✭✭pauldry


    Do we have to go to the Nederlands to see blue sky?

    Actually if you set fire to any photo for a milisecond would you get the same effect


  • Registered Users Posts: 22,198 ✭✭✭✭endacl


    How come no stars are visible in that photo?

    Too bright for the stars to show up, and slightly cloudy over most of the image.


  • Registered Users Posts: 6,235 ✭✭✭Oneiric 3




  • Registered Users Posts: 462 ✭✭oriel36


    The distance from observer to horizon acts like a giant sun visor to events close to the inner solar system or where the Sun's glare swamps observation. Nowhere is this more apparent than the ISS where the horizon is the Earth itself -

    https://www.youtube.com/watch?v=Yh1_wHdUx3Y&t=114s


    In a mini version of this, the distance from observer to horizon as a twilight appearance shows objects close to the left of the Sun while a dawn appearance shows objects to the right of the Sun. This is why comet neowise is to the left of the Sun and will become a largely twilight appearance as viewed from the orbital plane of the Earth.

    https://theskylive.com/planetarium?objects=sun-moon-c2020f3-mercury-venus-mars-jupiter-saturn-uranus-neptune-pluto&localdata=51.48%7C0%7CGreenwich%2C+United+Kingdom%7CEurope%2FLondon%7C0&obj=c2020f3&h=12&m=15&date=2020-07-17#ra|7.879943777327864|dec|42.32479332747845|fov|80

    There is nothing offensive in this description, however, those who choose to express the comet in terms of a plethora of objects rising and setting based on daily rotation fall far short of the relationship of the comet to the moving Earth and the stationary/central Sun. Far more enjoyable and challenging this way as it is much more than just identification. It is not for everyone but for those who can, there is a satisfaction involved like no other,at least in these matters.


  • Registered Users Posts: 14,279 ✭✭✭✭M.T. Cranium


    Getting brighter, I just got in from a clear sky late evening view here, and would say it has brightened by perhaps 20 or 25 per cent over two days. It is closing in on the first pair of stars shown in my earlier diagram (lower right of the bowl of the Big Dipper). If you get a chance this evening in any part of Ireland, it can be located from this chart although you'll probably see the comet before you find the two stars it is approaching. The next night it should be moving through that gap (possibly before your turn so I may see that from here on Sunday evening).

    So I have taken the original diagram and edited it as follows for tonight (19th 00z roughly).

    .................................................NW.......................................................NNW......
    ....................................0.....................................................................................
    ....................0..............................0........................................................................
    ....................................................................0.............................................................
    ...................................................................................0.....................................................
    ..................................................................0.........................................................................
    .................................................................................0...........................................................
    ..............................................................................................................................................
    ...........................o..................................................................................................................
    ...............................................................................................................................................
    .........................o.........................................................................o.........!.............................:.
    .................................................................................................o..........!!............................:...
    ............................................................................................................@.............................:..
    ...............................................................................................................................................
    ...................................................................................................Comet 18th-19th ...................

    (the comet is steadily moving right to left or west and will eventually be near the next pair of stars shown
    below the handle of the plough/dipper.


  • Registered Users Posts: 462 ✭✭oriel36


    (the comet is steadily moving right to left or west and will eventually be near the next pair of stars shown
    below the handle of the plough/dipper.

    It takes quite an effort to translate the transition from a morning appearance to an evening appearance of a celestial object or as it moves from right to left of the Sun as viewed from the orbital plane. You are trying to include daily rotational East and West coordinates and that defeats the whole purpose of relating the comet to the central Sun and the moving Earth.

    The Earth is constantly shifting axial orientation to the Sun as the North pole moves in a small circle parallel to the orbital plane over the course of a year like so -

    https://qph.fs.quoracdn.net/main-qimg-bc3b5688f8ec0f30f7823b47576d1341.webp


    Unfortunately a moderator sought to close down the other thread for some unwarranted reason of anger which I don't have as untangling the issue of what is left or right of the Sun or from a dawn to twilight appearance can be challenging at first for any observer. It intersects with weather and seasonal weather patterns in the way the original framework of Copernicus (which needed modification anyway) was lost to the 17th century RA/Dec modelers who attempted to make the Earth's daily rotation the basis for observations.

    The graphic above is accounted for in a description of Copernicus which he jettisoned by the time he wrote De Revolutionibus. It would take 500 years until the emergence of satellite imaging to demonstrate what that motion parallel to the orbital plane looks like -

    "The third is the motion in declination. For, the axis of the daily rotation is not parallel to the Grand Orb's axis, but is inclined [to it at an angle that intercepts] a portion of a circumference, in our time about 23 1/2°. Therefore, while the earth's center always remains in the plane of the ecliptic, that is, in the circumference of a circle of the Grand Orb, the earth's poles rotate, both of them describing small circles about centers [lying on a line that moves] parallel to the Grand Orb's axis. The period of this motion also is a year, but not quite, being nearly equal to the Grand Orb's [revolution]. The Grand Orb's axis, however, being invariant with regard to the firmament, is directed toward what are called the poles of the ecliptic." Copernicus

    http://copernicus.torun.pl/en/archives/astronomical/1/?view=transkrypcja&

    In conclusion, when the comet moves from right to left of the Sun as it has been doing over the last week or so, the description is based on how we see the comet from the orbital plane of the Earth. It is why the ISS imaging is so compelling in this respect -

    https://www.youtube.com/watch?v=Yh1_wHdUx3Y&t=122s


    The more observers become familiar with the astronomical relationships involved with the comet, the more the curtain rises on the satisfaction gained by linking the motions of the planet to weather and climate as they truly exist.


  • Moderators, Science, Health & Environment Moderators Posts: 11,766 Mod ✭✭✭✭Meteorite58


    Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.


    BugUeTd.jpg?1


  • Registered Users Posts: 12,941 ✭✭✭✭Purple Mountain


    Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.


    BugUeTd.jpg?1

    What time will Bob and Doug and the Russians zoom past again tonight?

    To thine own self be true



  • Registered Users Posts: 5,561 ✭✭✭quad_red


    Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.


    BugUeTd.jpg?1

    Went out there myself. Wall of cloud.


  • Registered Users Posts: 5,561 ✭✭✭quad_red


    Not great but seemed to have caught a satellite passing this evening. Might go out again, very cold and the lens keeps getting coated in condensation.


    BugUeTd.jpg?1

    Ah good stuff.

    Went out myself and bank of cloud where it should be. Waited a while to see if it would move but no luck.

    Will try again tomorrow.


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  • Registered Users Posts: 6,834 ✭✭✭pauldry


    Was miraculously clear in Sligo but still didnt see and I drove up the hills. Cloudy now so no chance. Downloaded Stellarium and it's still not visible. Might drive up hills late tomorrow night if clear


  • Registered Users Posts: 6,335 ✭✭✭SouthWesterly


    Clear night in North Kerry.
    Got some nice shots
    Not as clear to the naked eye as last week


  • Registered Users Posts: 6,834 ✭✭✭pauldry


    Completely clear in Sligo now but cant see it. Off to bed.


  • Registered Users Posts: 12,941 ✭✭✭✭Purple Mountain


    I can see every other star in the sky but no comet :(

    To thine own self be true



  • Moderators, Science, Health & Environment Moderators Posts: 11,766 Mod ✭✭✭✭Meteorite58


    I can see every other star in the sky but no comet :(

    Fairly faint now but use the plough as a guide.....


    IIfIedZ.png


  • Registered Users Posts: 12,941 ✭✭✭✭Purple Mountain


    Fairly faint now but use the plough as a guide.....


    IIfIedZ.png

    Thanks, I was looking under the Plough but like you said it's faint.

    To thine own self be true



  • Registered Users Posts: 854 ✭✭✭beveragelady


    Delighted with myself! I've been hauling myself and some confused dogs up the hill behind my house every night looking for Neowise without ever a hope of seeing it. Finally saw it tonight, much bigger than I expected but not very bright (bit like myself). It's cold and clear out there tonight, very rewarding skygazing.


  • Registered Users Posts: 2,323 ✭✭✭lolie


    Definitely getting a bit dimmer now.
    Pics-Art-07-19-03-27-52.jpg


  • Moderators, Society & Culture Moderators Posts: 12,592 Mod ✭✭✭✭riffmongous


    What time are you guys seeing it at?


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  • Registered Users Posts: 14,279 ✭✭✭✭M.T. Cranium


    It can be seen all night as it's well above the northern horizon, moving from NNW to NNE between 10:30 pm and 3:30 a.m. (roughly the interval of dark skies). There is no best time to see it, depends on your local horizon and viewing parameters. However, it may be about to fade rapidly. I'm eight hours behind your time zone and waiting for darkness to have a look (sun just set here at 9 p.m. local time). Will report back how it compares to last two views I had.

    (later edit) _ Just back in from viewing, would say it has dropped in brightness by about one magnitude past two days, it's about equal to the two guide stars it just passed. At best it is borderline of 2nd and 3rd mags. Still a good sight in binoculars. If you don't have very dark rural skies plus binocs, I would say not worth your time or effort now, but try for it if you have those two things.


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