Finding the correct coordinates for a galaxy?

[Reiko]

With the new patch I want to place stars in a nearby galaxy using Globular Cluster Generator 1.3
My problem is finding to exact coordinates of the galaxy I want. I looked up the galaxy in question in the deepsky.dsc in this is what I found

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Galaxy "Sagittarius dSph"
{
        Type  "E6"
        RA           18.9175
        Dec         -30.4783
        Distance   6.523e+04 # method: rgb
        Radius          4240
        AbsMag        -12.67
        Axis    [ -0.6749  -0.5467  -0.4956]
        Angle    127.9516
        InfoURL  "http://simbad.u-strasbg.fr/sim-id.pl?Ident=Sagittarius dSph"
}

When I use those coordinates in the DSC file the star cluster misses the galaxy but when I use the coordinates listed at that ulr

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RA 18 55 03.1
Dec -30 28 42

It places it perfectly so is there a conversion process I am missing?

how does this
RA 18.9175
Dec -30.4783

become this

RA 18 55 03.1
Dec -30 28 42

[Chuft-Captain]

The 18 55 02.1 is in H.m.s format. Celestia requires RA to be expressed as a decimal number. You need to convert the H.m.s form to decimal.

Use the formula: hours + (minutes/60) + (seconds/3600)

eg. 18 + 55/60 + 3.1/3600 = 18.91752778

[Hungry4info]

Perhaps sometime Celestia could recognize Sexagesimal (DMS), or in HMS, or whatever.

[LordFerret]

This accomplished the same results though it's not meant for this...

I used the RA value for latitude and the Dec value for longitude.
http://www.fcc.gov/mb/audio/bickel/DDDMMSS-decimal.html

[Reiko]

Thank you guys.

[selden]

Celestia's use of RA is somewhat confusing:
RA must be entered as fractional Degrees (0-360) when specified in an STC (STar) file,
but must be entered as fractional Hours (0-24) when specified in a DSC (Deep Space) file.