Astronomy Picture of the Day . At the Edge of the Helix . ... Credit: R. O'Dell and K. Handron (Rice University ), NASA Explanation: While exploring the inner edge of the Helix Nebula with the Hubble Space Telescope's Wide Field Planetary Camera 2 , astronomers were able to produce this striking image - rich in details of an exotic environment. This planetary nebula, created near the final phase of a sun-like star's life , is composed of tenuous shells of gas ejected by the hot central star. ...