Astroblog

Location of Ceres as seen looking east from Adelaide at 19:17 ACST (90 minutes after sunset) on Friday 28 August, when it is at opposition. Similar views will be seen elsewhere in Australia 90 minutes after sunset (click to embiggen)	Approximate view in 10x50 binoculars at the same time, use the bright star Fomalhaut, the brightest star above the eastern horizon at this time, as your guide. (click to embiggen)

Ceres is the second largest dwarf planet after Pluto and the only dwarf planet in the inner solar system. It comes to opposition, when it is biggest and brightest, on Friday August 28. It won't be spectacular at magnitude 7.7 you will need good binoculars to see it as a point of light and you will need to watch it move over several days to see it move to be sure you have seen it. But it will be cool to say you have seen a water world in the skies.

Black and white spotters map suitable for printing, the circle is the approximate field of view of 10x50 binoculars. the orientation is the same as in the binocular chart above, in that chart c2 Aqr is the same as 88 Aquarii. Click to embiggen and print

Labels: Asteroid, binocular, Ceres, Dwarf Planet

Charon simulated in Celestia with the Charon Global Map used to generate the Charon texture. Click to embiggen

The Charon Global Map has just been released to complement the Pluto Global Map, so I resized it (1024x512) and converted it to a 72 DPI png to use as a texture for  Celestia.

You need to copy the texture file  Charon.png  to the textures/medres folder in the Celestia directory, then edit the solarsys.ssc file in the data folder (make a backup copy first) to replace the texture name in the Pluto definition section with that of the new texture, save it and you are good to go (just as you did for Pluto).

"Charon:Pluto I:134340 Pluto I:1978 P 1" "Sol/Pluto"
{
    Texture "Charon.*"
    SpecularTexture "charon-lok-spec.*"
    SpecularColor            [ 0.135 0.12 0.08 ]
    SpecularPower             9.5

Now I have to learn how to do XYZ or SPICE orbits to add in the New Horizons flyby. And also fix the north polar alignments.

Labels: celestia, Dwarf Planet, Pluto

Pluto simulated in Celestia with the Pluto Global Map used to generate the Pluto texture. Click to embiggen

The Pluto Global Map has just been released, so I resized it (1024x512) and conveyed it to a 71 DPI png to use as a texture for  Celestia.

You need to copy the texture file  pluto_surface1.png  to the textures/medres folder in the Celestia directory, then edit the solarsys.ssc file in the data folder (make a backup copy first) to replace the texture name in the Pluto definition section with that of the new texture, save it and you are good to go.

"Pluto:134340 Pluto" "Sol"
{
    Class "dwarfplanet"
    Texture "pluto_surface1.*"
    SpecularTexture "pluto-lok-spec.*"
    SpecularColor            [ 0.135 0.12 0.08 ]
    SpecularPower             9.5

Now waiting for the Charon map. Then I have to learn how to do XYZ or SPICE orbits to add in the New Horizons flyby.

Labels: celestia, Dwarf Planet, Pluto

Close up view of the outer solar system showing the two new objects 2013 FY27 and 2013 FZ27, the orbit of Pluto is highlighted for comparison. Click to embiggen	More distant view of the outer solar system showing 2012 VP113, its is highlighted. The orbit of Sedna does not fit even at this scae.Click to embiggen,

In quick succession the team of Scott Sheppard and Chad Trujillo at the Cerro Tololo Inter-American Observatory have announced 3 new Dwarf planets. 2012 VP113 has an enormous 4000 year long orbit, and represent an object from the inner edge. The two others 2013 FY27 and 2013 FZ27 are more "traditional" Scattered disk objects (that seems ironic now).

Once again I have made a Celestia file, three files actually. In the clestia download I use, Sedna was ilsted as an Asterid, bot a dwarf planet, so if its orbot doesn't turn up when you enable Dwarf Planets in Render | View Otions, but does when you turn on Asteroids, go to the data folder, find outersys.ssc (save a cpopy just in case), open and scroll down to Sedna and replace Class "asteroid" with Class "dwarfplanet".  

As usual, copy the data here to a plain text file ( 2012VP113.ssc etc.) and copy the file to the Celestia extras folder.

========================2012VP113.ssc==================================
"2012 VP113" "Sol"

#Sedna like inner Oort cloud object
#Data from MPC http://cfa-www.harvard.edu/iau/MPEph/MPEph.html
#Epoch 2014 May 23.0 TT = JDT 2456800.5                  MPC
#M   3.06601              (2000.0)            P               Q
#n   0.00021494     Peri.  291.14923     +0.84619626     -0.34404613             T = 2442536.18257 JDT
#a 276.0078196      Node    90.89192     +0.49413218     +0.79246630             q =    79.8521916
#e   0.7106887      Incl.   24.01461     -0.19946247     +0.50361634
#P4585              H    4.1           G   0.15           U   6
#From 24 observations at 2 oppositions, 2012-2013, mean residual 0".24.

{
    Class "dwarfplanet"
    Texture "pluto-lok.*"
    SpecularTexture "pluto-lok-spec.*"
    SpecularColor            [ 0.135 0.12 0.08 ]
    SpecularPower             9.5
    Radius  500 # maximum semi-axis
	

	InfoURL "http://en.wikipedia.org/wiki/2012_VP113"

	EllipticalOrbit
	{
	Epoch                  2456800.5      # Epoch 2014 May 23.0 TT = JDT 2456800.5
	Period                 4585           # P
	SemiMajorAxis          276.0078196    # a
	Eccentricity           0.7106887      # e
	Inclination            24.01461       # Incl.
	AscendingNode          90.89192       # Node
	ArgOfPericenter       291.14923       # Peri
        PericenterDistance      79.8521916    # q
        MeanAnomaly              3.06601      # M 
	}

	RotationPeriod 0.9 #Guess

	Albedo 0.4        #Based on Sedna

}

==========================================================
=======================2013FY27.ssc===================================
"2013 FY27" "Sol"

#Eris-like scattered disk object
#Data from MPC http://cfa-www.harvard.edu/iau/MPEph/MPEph.html
#Epoch 2014 May 23.0 TT = JDT 2456800.5                  MPC
#M 214.46118              (2000.0)            P               Q
#n   0.00216253     Peri.  136.72941     +0.79347223     +0.60486455             T = 2524100.74140 JDT
#a  59.2235677      Node   187.09259     -0.58925583     +0.79121780             q =    35.8742198
#e   0.3942577      Incl.   33.07550     +0.15224777     -0.09007372
#P 456              H    3.0           G   0.15           U   8
#From 12 observations at 2 oppositions, 2013-2014, mean residual 0".27.

{
    Class "dwarfplanet"
    Texture "pluto-lok.*"
    SpecularTexture "pluto-lok-spec.*"
    SpecularColor            [ 0.135 0.12 0.08 ]
    SpecularPower             9.5
    Radius  500 # maximum semi-axis
	

	InfoURL "http://en.wikipedia.org/wiki/2013_FY27"

	EllipticalOrbit
	{
	Epoch                  2456800.5      # Epoch 2014 May 23.0 TT = JDT 2456800.5
	Period                 456            # P
	SemiMajorAxis          59.2235677     # a
	Eccentricity            0.3942577     # e
	Inclination            33.07550       # Incl.
	AscendingNode         187.09259       # Node
	ArgOfPericenter       136.72941       # Peri
        PericenterDistance     35.8742198     # q
        MeanAnomaly           214.46118       # M 
	}

	RotationPeriod 0.9 #Guess

	Albedo 0.14        #Theortically expected

}

==========================================================
======================2013FZ27.ssc====================================
"2013 FZ27" "Sol"

#Eris-like scattered disk object
#Data from MPC http://cfa-www.harvard.edu/iau/MPEph/MPEph.html
#Epoch 2014 May 23.0 TT = JDT 2456800.5                  MPC
#M 277.75427              (2000.0)            P               Q
#n   0.00293700     Peri.  341.17225     -0.05888594     +0.97046090             T = 2484803.84051 JDT
#a  48.2910933      Node   284.91917     -0.88199787     -0.16035023             q =    38.0092953
#e   0.2129129      Incl.   14.01192     -0.46755985     +0.18025938
#P 336              H    4.4           G   0.15           U   6
#From 17 observations at 2 oppositions, 2013-2014, mean residual 0".42.

{
    Class "dwarfplanet"
    Texture "pluto-lok.*"
    SpecularTexture "pluto-lok-spec.*"
    SpecularColor            [ 0.135 0.12 0.08 ]
    SpecularPower             9.5
    Radius  500 # maximum semi-axis
	

	InfoURL "http://en.wikipedia.org/wiki/2013_FZ27"

	EllipticalOrbit
	{
	Epoch                  2456800.5      # Epoch 2014 May 23.0 TT = JDT 2456800.5
	Period                 336            # P
	SemiMajorAxis          48.2910933     # a
	Eccentricity            0.2129129     # e
	Inclination            14.01192       # Incl.
	AscendingNode         284.91917       # Node
	ArgOfPericenter       341.17225       # Peri
        PericenterDistance     38.0092953     # q
        MeanAnomaly           277.75427       # M 
	}

	RotationPeriod 0.9 #Guess

	Albedo 0.14        #Theortically expected

}

==========================================================

Labels: celestia, Dwarf Planet, Eris, Pluto