How do planetary nebulae acquire their exquisite geometrical shapes ? To investigate this, astronomers used the Hubble Space Telescope to image several young planetary nebulae . These nebulae are the outer envelopes of stars like our Sun that have recently been cast away to space, leaving behind a core fading to become a white dwarf . In this photograph in red H-alpha carbon that composes humans is thought to be created by red giant stars and ejected into the cosmos in planetary nebulae like PKS285-02. The complexity of this nebula leads some astronomers to hypothesize that these shells were created by high-speed, collimated outflows during a late phase of this star's evolution .
PKS285 02: A Young Planetary Nebula
Astronomy Picture of the Day · 1999-06-22 · NASA (public domain)
