Crosswords!
(java enhanced)

4. You will receive 10 points for each correct letter. However, you will lose 15 points for each letter you cheat on! To continue to a new puzzle, you must have at least 40 points or have correctly answered all the clues.

5. If you get stuck on a word, you can always cheat (but you have to have enough points!).

6. If you finish a puzzle and you still want more, just hit the "NEW PUZZLE" button. It will keep generating new puzzles until you have exhausted all of our words. Then you can start again. The puzzles are never the same!

Hint: If you have trouble finding an answer, check the Glossary or Field Guide to X-ray Astronomy for clues.

Play the puzzle!.