Note: Ultraviolet Image Not Available
Visible: Color FORS Team, 8.2-meter VLT, ESO (left) and Visible: TIE(right)
The color images of Messier 27 are similar, although the TIE photo is a deeper exposure. How can you tell? The central star is about a thousand times fainter than what could be seen by the naked eye in dark-sky conditions. However, photographic emulsions and detectors are far better light sensors than the human eye, and the central star is visible in the TIE image.
The black-and-white DSS image is over-exposed. That is, the exposure time is sufficiently long that the central regions of the nebula suffer from saturation, or "white out". The most fascinating thing about the image, however, is the trace of a very faint outer shell of gas, about half way to the edge of the image (the ring is particularly noticeable in the north half of the photo. This is evidence of an earlier ejection of a gas shell from the central star, one that was thrown out thousands of years before the inner shell. These shells are approximately spherical in shape (like the central star). The fact that such shells appear as rings is a result of the geometry of how we seen the ejecta. Our line of sight passes through more of the luminous shell along its edge, and hence the shell appears as a bright ring along those edges.
Note how the planetary nebula nearly disappears in the near-infrared. By clicking on the 2MASS image in the preview matrix at the top of this page, you can vaguely trace out the dumbbell shape of the nebula (in red). For the most part, near-IR light passes through gas and dust, and hence we see the rich background of stars that would otherwise be obscured by the planetary nebula.
Mid-Infrared: IRAS (left) and Far-Infrared: IRAS (right)
The mid- and far-infrared views of Messier 27 (above) were obtained by the IRAS satellite at wavelengths of 25 and 60 microns, respectively. Recall that the detectors used aboard this early infrared observatory had relatively poor spatial resolution (at least by today's standards!). Hence, the nebula appears as a blob. At these wavelengths, most of the infrared emission is due primarily to dust particles mixed within the gas of the nebula.
Radio: NVSS (left) and X-Ray: ROSAT (right)
The radio (above left) and x-ray (above right) images of Messier 27 reveal a centralized core of emission, although very little detail is seen in either photo. About all we can say, based on these data, is that M27 emits some radio waves and x-rays.