Go to: LONG STAR The Hubble Space Telescope spotted one of the longest known planetary nebulas, a dying star known as Henize 3-401. Scientists remain unsure how spherical stars become such odd-looking structures, but speculate that magnetic fields or companion stars stretch them into eccentric shapes. Planetary nebula and more powerful supernova explosions disperse huge amounts of heavy elements, which provide material for new stars and planets. (07/24/02)