  Cooper pairs of mutually attracting electrons form the building blocks of
superconductivity. Thirty years after the discovery of high-temperature
superconductivity in cuprates, many details of the pairs remain unknown,
including their size and shape. Here we apply brand new ARPES-based methods
that allow us to reconstruct the shape and size of the pairs in
Bi$_2$Sr$_2$CaCu$_2$O$_{8+{\delta}}$. The pairs are seen to form a
characteristic starfish shape that is very long (>50{\AA}) in the near-nodal
direction but extremely short (~4.5{\AA}) in the antinodal (Cu-O) direction. We
find that this ultrashort antinodal length scale, which is of order a lattice
constant, is approximately constant over a wide range of doping levels even as
many other parameters including the pairing strength change. This suggests that
this new length scale, along with the pair shape, is one of the most
fundamental characteristics of the pairs. Further, the shape and ultrashort
length scale should make the pairs create or intertwine with variations in
charge and pair density, center on various types of lattice positions, and
potentially explain aspects of the nematic order in these materials.
