
This Hubble telescope snapshot of MyCn18, a young planetary nebula, reveals that the object has an hourglass shape with an intricate pattern of etchings in its walls. A planetary nebula is the glowing relic of a dying, Sun-like star.

Taken by the Wide Field Planetary Camera 2 (WFPC2) of the Hubble Space Telescope (HST), this image of MyCn18, a young planetary nebula located about 8,000 light-years away, reveals its true shape to be an hourglass with an intricate pattern of "etchings" in its walls. The arc-like etchings could be the remnants of discrete shells ejected from the star when it was younger, flow instabilities, or could result from the action of a narrow beam of matter impinging on the hourglass walls. According to one theory on the formation of planetary nebulae, the hourglass shape is produced by the expansion of a fast stellar wind within a slowly expanding cloud, which is denser near its equator than near its poles. Hubble has also revealed other features in MyCn18 which are completely new and unexpected. For example, there is a pair of intersecting elliptical rings in the central region which appear to be the rims of a smaller hourglass. This picture has been composed from three separate images taken in the light of ionized nitrogen (represented by red), hydrogen (green) and doubly-ionized oxygen (blue). The results are of great interest because they shed new light on the poorly understood ejection of stellar matter which accompanies the slow death of sun-like stars. An unseen companion star and accompanying gravitational effects may well be necessary in order to explain the structure of MyCn18. The Marshall Space Flight Center (MSFC) had responsibility for design, development, and construction of the HST.

This image was compiled using data from NASA's Spitzer Space Telescope using the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer (MIPS) during Spitzer's "cold" mission, before the spacecraft's liquid helium coolant ran out in 2009. The colors correspond with IRAC wavelengths of 3.6 microns (blue), 4.5 microns (cyan) and 8 microns (green), and 24 microns (red) from the MIPS instrument. The green-and-orange delta filling most of this image is a nebula, or a cloud of gas and dust. This region formed from a much larger cloud of gas and dust that has been carved away by radiation from stars. The bright region at the tip of the nebula is dust that has been heated by the stars' radiation, which creates the surrounding red glow. The white color is the combination of four colors (blue, green, orange and red), each representing a different wavelength of infrared light, which is invisible to human eyes. The massive stars illuminating this region belong to a star cluster that extends above the white spot. On the left side of this image, a dark filament runs horizontally through the green cloud. A smattering of baby stars (the red and yellow dots) appear inside it. Known as Cepheus C, the area is a particularly dense concentration of gas and dust where infant stars form. This region is called Cepheus C because it lies in the constellation Cepheus, which can be found near the constellation Cassiopeia. Cepheus-C is about 6 light-years long, and lies about 40 light-years from the bright spot at the tip of the nebula. The small, red hourglass shape just below Cepheus C is V374 Ceph. Astronomers studying this massive star have speculated that it might be surrounded by a nearly edge-on disk of dark, dusty material. The dark cones extending to the right and left of the star are a shadow of that disk. The smaller nebula on the right side of the image includes a blue star crowned by a small, red arc of light. This "runaway star" is plowing through the gas and dust at a rapid clip, creating a shock wave or "bow shock" in front of itself. https://photojournal.jpl.nasa.gov/catalog/PIA23126

It may look like something from "The Lord of the Rings," but this fiery swirl is actually a planetary nebula known as ESO 456-67. Set against a backdrop of bright stars, the rust-colored object lies in the constellation of Sagittarius (The Archer), in the southern sky. In this image of ESO 456-67, it is possible to see the various layers of material expelled by the central star. Each appears in a different hue - red, orange, yellow, and green-tinted bands of gas are visible, with clear patches of space at the heart of the nebula. It is not fully understood how planetary nebulae form such a wide variety of shapes and structures; some appear to be spherical, some elliptical, others shoot material in waves from their polar regions, some look like hourglasses or figures of eight, and others resemble large, messy stellar explosions - to name but a few. Image Credit: ESA/Hubble and NASA <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b> <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b> <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b> <b>Find us on <a href="http://instagram.com/nasagoddard?vm=grid" rel="nofollow">Instagram</a></b>
The bipolar star-forming region, called Sharpless 2-106, looks like a soaring, celestial snow angel. The outstretched “wings” of the nebula record the contrasting imprint of heat and motion against the backdrop of a colder medium. Twin lobes of super-hot gas, glowing blue in this image, stretch outward from the central star. This hot gas creates the “wings” of our angel. A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into an “hourglass” shape. To read more about this image go to: <a href="http://www.nasa.gov/mission_pages/hubble/science/snow-angel.html" rel="nofollow">www.nasa.gov/mission_pages/hubble/science/snow-angel.html</a> Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA) <b><a href="http://www.nasa.gov/audience/formedia/features/MP_Photo_Guidelines.html" rel="nofollow">NASA image use policy.</a></b> <b><a href="http://www.nasa.gov/centers/goddard/home/index.html" rel="nofollow">NASA Goddard Space Flight Center</a></b> enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. <b>Follow us on <a href="http://twitter.com/NASA_GoddardPix" rel="nofollow">Twitter</a></b> <b>Like us on <a href="http://www.facebook.com/pages/Greenbelt-MD/NASA-Goddard/395013845897?ref=tsd" rel="nofollow">Facebook</a></b> <b>Find us on <a href="http://instagrid.me/nasagoddard/?vm=grid" rel="nofollow">Instagram</a></b>