Flying Saucer Shape

    Keywords: Life & Death

The Flying Saucer Shape is dead

The Flying Saucer Shape is dead  

The critical elements are

  1. the black group's weak spots are occupied by White (white+square stones),
  2. the black group is blocked on the second line at both ends (white+circle stones), and
  3. these white blocking stones are connected to the rest of the white group (white+triangle stones).

It is not critical whether the circled liberties are occupied or not.

For an example of a flying saucer position where the third critical element is missing, see Gokyo Shumyo, Section 1, Problem 23.

For a general treatment, see Two Space Notchers Not Fully Connected.

Black Attempts to Live

Attempt 1  

White cuts at the other side than the one Black protects, then gives atari. She finishes off with W6, keeping Black at one eye. The position is symmetric, so if B1 at 3 then W2 at 5.

Attempt 2  

Black ends up with a 3 point big eye with W2 already at the vital point.

Attempt 3  

After W2, Black has a shape similar to six on the second row. He's dead. B3 gives major resistance, but after W4, she can almost fill Black's eye space with three stones any time.

Attempt 4  

This reverts to attempt 3.

Attempt 5  
Attempt 5 - alternative  


Flying Saucer Shape last edited by RobertPauli on November 30, 2017 - 14:58
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