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PostPosted: Tue, 18-12-18, 16:00 GMT 
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Here is the link to the discovery announcement:
Quote:
Washington, DC— A team of astronomers has discovered the most-distant body ever observed in our Solar System. It is the first known Solar System object that has been detected at a distance that is more than 100 times farther than Earth is from the Sun...


https://carnegiescience.edu/news/discov ... r-observed

Cheers,
Fridger

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PostPosted: Fri, 21-12-18, 3:06 GMT 
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the telnet Horizons site has a spice kernel for this one already
4k images
Attachment:
2018VG18.png
2018VG18.png [ 7.23 MiB | Viewed 552 times ]


Attachment:
2018VG18Normal.png
2018VG18Normal.png [ 16 MiB | Viewed 552 times ]



Code:


#telnet ssd.jpl.nasa.gov 6775


 "2018_VG18:3836918" "Sol"

{
   Class   "dwarfplanet"
  Texture "2018VG18.png"
  NormalMap "2018VG18Normal.png"
  Radius 250
  SpecularColor   [ 0.07 0.06 0.06 ]
  SpecularPower   1.0
   OrbitColor      [ 1 1 0]
  Albedo               0.2  # guess, a bit random

  OrbitFrame { EclipticJ2000 { Center "SSB" }}

  Beginning  " 1000 01 06 00:00:00.000 "
  Ending     " 2101 01 01 00:00:00.000 "

  SpiceOrbit
  {
    Kernel  "2018VG18.bsp"
    Target "3836918"
    Origin "0"
    Period  1101
    BoundingRadius 5e10
  }
   PrecessingRotation
  {
    Inclination        5        # random
    Period             100       # random
    PrecessionPeriod   0.01     # random
  }

}

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Last edited by John Van Vliet on Sat, 22-12-18, 4:37 GMT, edited 1 time in total.

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PostPosted: Fri, 21-12-18, 7:57 GMT 
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How nice, John!

many thanks! I am highly interested...

Cheers
Fridger

PS: didn't yet succeed finding & downloading the 2018VG18.bsp Spice kernel ...I guess with help of your fine instructions for comet Halley it can't be too difficult eventually.

I very much like your modeling of the 2018VG18 surface. Did you have a particular reason for not adding a bit of pink as was claimed in the original paper? Assuming the color reflects some icy surface, I wonder where the pink color should come from, given our G2V Sun as the iluminator?

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PostPosted: Sat, 22-12-18, 4:49 GMT 
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CORRECTION
i used telnet and not ftp -- oops
Attachment:
Screenshot_20181221_234240.png
Screenshot_20181221_234240.png [ 260.33 KiB | Viewed 523 times ]



a redish tint is easier in blender than a bit pink
( the blue in it just dose not look good )

a small edit to the ssc using "blendtrue" can add a bit of blue to the redish tholian tint

EVERYONE feel free to add corrections, we ARE a community here after all.

PS. added a bit latter

here is a link to the bsp on my G-drive ( 533 Kb zip )
https://drive.google.com/file/d/1SK5uZ9 ... sp=sharing



.

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PostPosted: Sat, 22-12-18, 13:35 GMT 
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Thanks a lot, John, for the 2018VG18.bsp kernel link and the telnet "template" above. This was useful, indeed, and got me back on telnet after decades of "abstinence" ;-) ...

The 2018VG18.bsp kernel works just fine.

As to the pink texture issue, I played quickly a bit tuning the SpecularColor mix e.g. like so:
SpecularColor [ 0.1 0.05 0.25 ]

This gives a pink tone, but so far lacks any authority from real data.

[click on image for a bigger size]
Attachment:
Screenshot_20181222_141020.png
Screenshot_20181222_141020.png [ 1.09 MiB | Viewed 514 times ]


I also noted a few imperfections at various places on the surface (NormalMap), e.g. looking like this
Attachment:
Screenshot_20181222_141555.png
Screenshot_20181222_141555.png [ 348.34 KiB | Viewed 514 times ]


Could these dark edges be removed easily in Blender? You know I have never touched Blender ;-)

Cheers and thanks again for your help,
Fridger

PS: I kept wondering what the base of the pink color statement could have been. Hence I looked at the discovery photo from the Japanese 8.2 m Subaru telescope at high magnification:
Attachment:
Screenshot_20181222_155148.png
Screenshot_20181222_155148.png [ 104.11 KiB | Viewed 509 times ]


Look at the tip of the green arrow: this is 2018 VG18 and with some imagination one may indeed see a slightly pinkish-blue dot. So I quantitatively measured the screen color at the star and got this color frame:
Attachment:
Screenshot_20181222_160901.png
Screenshot_20181222_160901.png [ 256 Bytes | Viewed 509 times ]


Well, it looks like dark gray with a barely visible blue-pinkish touch, corresponding to this RGB
color mix [ 137 128 136].
As you can see the colors red and blue are a bit enhanced relative to the green, i.e. there is some slight deviation from a pure gray color.

Is this the whole evidence of the color of 2018 VG18 or does anybody know another argument?

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PostPosted: Sat, 22-12-18, 16:02 GMT 
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Quote:
I also noted a few imperfections at various places on the surface (NormalMap), e.g. looking like this


i saw those too last night an fixed them , will post an update in the spice section with a full add on that is more pink

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PostPosted: Tue, 25-12-18, 9:41 GMT 
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John,

since pink is an English (i.e. not German) color designation with many shades, it turns out that my vision of "pink" was too blue. I looked up the "official" pink. Here it is

Attachment:
Screenshot_20181225_130045.png
Screenshot_20181225_130045.png [ 2.38 KiB | Viewed 476 times ]

of course with appropriate value (V) suppression applied. Actually, it seems your original shade of 2018 VG18 was pretty close to a dark pink. Sorry...

This shade would typically correspond to a not so much darkened pink : SpecularColor [ 0.647 0.533 0.584 ]
[click on image for an appropriate size]
Attachment:
Screenshot_20181225_133052.png
Screenshot_20181225_133052.png [ 663.41 KiB | Viewed 475 times ]

Yet, the dwarfplanet's illumination should be much weaker, since the Sun is so far away... :rool:

Cheers,
Fridger

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PostPosted: Tue, 25-12-18, 23:30 GMT 
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i posted a zip in the spice section

The color is more pinkish than the reddish i posted above

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PostPosted: Wed, 26-12-18, 9:59 GMT 
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John Van Vliet wrote:
i posted a zip in the spice section

The color is more pinkish than the reddish i posted above


Many thanks, John! Looking forward to playing with the texture tonight ...

Cheers,
Fridger

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