Doppler Astronomy
(Published yesterday, 16:00 by Blobz)
Normal sudoku rules apply.
Divide the grid into galaxies: orthogonally connected groups of cells that have 180 degree rotational symmetry about their centers (marked with a small dot). All cells must be part of a galaxy; no galaxies overlap.
Galaxies are either red-shifted (moving away from the observer), or blue-shifted (moving towards the observer). The measured value of each galaxy is shown; it is the sum of the digits in that galaxy PLUS (blue-shifted) or MINUS (red-shifted) the number of cells in the galaxy.
Dots with a solid black outline indicate "Renban" galaxies, whose digits form an unbroken consecutive sequence in any order. Conversely, dots without a solid black outline indicate galaxies whose digits do NOT form such a sequence.
Digits may not repeat within a galaxy.
Five single-cell galaxies — "Dark Stars" — are NOT marked: their locations must be deduced by the solver. All cells (max 8) around a Dark Star belong to regular galaxies. No 3x3 box contains more than one Dark Star. Digits do not repeat amongst the Dark Stars.
Have fun, leave a comment if you enjoy the puzzle!
Solution code: Row 7
Comments
today, 16:22 by Exigus
Very satisfying. Thanks!
today, 03:10 by kisukeA
One of the most interesting and beautiful puzzles of all time, it seems like the difficulty dropped to 3* as I was solving it, but i could still see this as a 4* puzzle, just brilliant.
yesterday, 21:14 by Hrothan
I'm not sure if this is just me, but I was confused by the "No 3x3 box contains more than one Dark Star" instruction.
It took me longer than I would like before realizing it was specifically for the nine standard marked 3x3 boxes in the Sudoku grid, not for any arbitrary 3x3 area (which is what I originally assumed).
