In this Star Battle puzzle, the goal is for each row, column, and region to have exactly two stars. No two stars may be adjacent, even diagonally. One solving path is provided here for reference:
- In the WHEE region, if there is a star on either the W or the first E, there is no room for a second star in the region. Therefore, there must be stars on the H and other E, and all squares around them are empty, as is the rest of the ninth row.
- Similarly, in the SPACE region, the S must have one star, and the other must be on A or C.
- In REDPLANET, most spaces have already been eliminated. There must be a star on either the R or E and another on either the E or T. The S of CAPRICORNS must be empty, since the bottom row already has two stars.
- The rightmost two columns contain a total of four stars. This includes one from the ET of REDPLANET, and two from PRESSURE. This means that at most one of the stars from the INCREASE region can be in the rightmost two columns, so there must be a star on the C of INCREASE, and there are no stars on the OCV of DOESANATUREABHORSPACETRAVEL.
- After eliminating the spaces around the C, the only remaining locations for a star in the ninth column are the ES of PRESSURE and the E of REDPLANET. The E of PHOTOCHEMISTRY and the SU in the tenth column of PRESSURE can be eliminated.
- At most one star can be on the IC of CAPRICORN. Since the first column already has a star from SPACE, the second star in that column must be in CAPR. The AT of HPPLANET must be empty, as must the EL of DOESNATUREABHORSPACETRAVEL.
- The stars in HPPLANET must be on P and either N or E. That eliminates the bordering spaces, as well as the rest of the now complete first row and fifth column.
- There is now only one location for the remaining star in SPACE, which leaves a single location for the remaining star in HPPLANET.
- There must be a star on the S and either the E or A of STARSEA. After eliminating the adjacent squares, there must be a star on the T and C or H of PHOTOCHEMISTRY.
- With the squares eliminated in the previous step, the eighth row stars must be on the I of CAPRICORNS and the S of PRESSURE. The four stars in the second and third column are in the first, third, eighth, and tenth rows, so any other spaces in those columns must be empty.
- There are now only two possible locations for stars in the fourth row. Those stars further limit the spaces in the sixth and fifth rows. It’s all cleanup now.
The completed grid looks like this:
The letters from the starred spaces spell out SPACESHIP EARTH IS HERE. Spaceship Earth is located at EPCOT, the answer to the puzzle.
Just for fun, here’s a picture of the grid, colorized:
