Original transcription by Geordie Keitt, revised by Suuuupaadave. (not me, but 
them on jonathancoulton.com)

Chords:

A       x0222x
Aaug    x0322x
D       xx0232
E.      022100
F#m/C#  x4422x
Faug/C# x4322x
A/C#    x4222x
B7      x21202
E7      022130
F#m/A   x0422x
A7      x02020
Dmaj7   xx0222
F#m     244222
Dm6     xx0201

Intro: |A |Aaug||A |Aaug|

Verse 1
A                            D             E
 This year has been a little crazy for the Andersons
A                           D            E
 You may recall we had some trouble last year
A                         D              E
 The robot council had us banished to an asteroid
A                           D       E
 That hasn't undermined our holiday cheer.

Pre-chorus 1
       F#m/C#           Faug/C#          A/C#                 B7
And we know it's almost Christmas by the marks we make on the wall.
           E        E/F#    E7/G#
That's our favorite time of year.

Chorus
      A              Aaug             F#m/A
Merry Christmas from Chiron Beta Prime,
            A7           Dmaj7              F#m
Where we're working in a mine for our robot overlords.
          B7                    E
Did I say overlords? I meant protectors.
      D              Dm6
Merry Christmas from Chiron Beta Prime.

A | Aaug | A | Aaug

Verse 2
A                          D           E
 On every corner there's a giant metal Santa Claus,
A                         D           E
 Who watches over us with glowing red eyes.
A                            D                   E
 They carry weapons and they know if you've been bad or good.
A                         D        E
 Not everybody's good but everyone tries.

Pre-chorus 2
        F#m/C#              Faug/C#       A/C#          B7
And the rocks outside the airlock exude ammonia-scented snow.
          E        E/F#    E7/G#
It's like a Winter Wonderland.

Chorus
      A              Aaug             F#m/A
Merry Christmas from Chiron Beta Prime,
            A7           Dmaj7              F#m
Where we're working in a mine for our robot overlords.
          B7                    E
Did I say overlords? I meant protectors.
      D              Dm6
Merry Christmas from Chiron Beta Prime.

[Keyboard solo. Same chords as Chorus]

A | Aaug | A | Aaug

Verse 3
A                                D                E
 That's all the family news that we're allowed to talk about.
A                               D        E
 We really hope you'll come and visit us soon.
A                       D              E
 I mean we're literally begging you to visit us.
A                               D               E
 And make it quick before they [MESSAGE REDACTED].

Pre-chorus 3
         F#m/C#             Faug/C#              A/C#             B7
Now it's time for Christmas dinner - I think the robots sent us a pie!
           E       E/F#    E7/G#
You know I love my soylent green.

Chorus
      A              Aaug             F#m/A
Merry Christmas from Chiron Beta Prime,
            A7           Dmaj7              F#m
Where we're working in a mine for our robot overlords.
          B7                    E
Did I say overlords? I meant protectors.
      D              Dm6
Merry Christmas from Chiron Beta Prime.