Credit: Rodger Thompson, Marcia Rieke, Glenn Schneider, Dean Hines (University of Arizona); Raghvendra Sahai (Jet Propulsion Laboratory); NICMOS Instrument Definition Team, and NASA
Explore this infrared image from the orbiting telescope. What stories or pictures do you see? Leave a note below.
The Egg Nebula, CRL 2688, is a planetary nebula. These bubbles of gas are all that remains of an aging star. When stars like the Sun reach the end of their lives, they throw off gas and dust layers. Scientists study the death of stars to understand how elements are returned to deep space. Elements, such as carbon and nitrogen, formed from the burning of hydrogen and helium deep within the stars. These elements are essential for Earth-bound life and for new stars and planets.
Planetary nebulae come in all shapes and sizes. Some, like the Ring Nebula or the Eight Burst Nebula, are smooth bubbles. Others, such as IC 4634, are much more jumbled. The equal rings around the Egg Nebula create a bubble around the star. The Egg Nebulas outer dust layers are one-tenth of a light-year from the star, more than 200 times larger than the orbit of Pluto in our solar system.
Infrared light is invisible to humans. The wavelength of light is slightly below the visible part of the spectrum that we can see. We feel it as heat though. Hubble’s Near Infrared Camera and Multi-Object Spectrometer, or NICMOS, can see through dust clouds to detect warm objects. Scientists assign different colors to different temperatures. Blue in this image is cool starlight reflected from dust particles. Red represents heat emitted from hot molecular hydrogen heated up as it slams into the calm gas and dust. The bubbles seem to be closed at the end as if bright material is blocking the high-speed gas inside. When compared to the dragonfly-like visible image, the bubbles match closely with the beams of light. The infrared image helps scientists understand that there is material between the beams of light, they just aren’t lit up.
The Egg Nebula is found about 300 light-years from Earth toward the constellation Cygnus, the Swan.