![]() The Red Rectangle is found about 2300 light-years away in the constellation Monoceros (the Unicorn). Once the expulsion of mass is complete a very hot white dwarf star will remain and its brilliant ultraviolet radiation will cause the surrounding gas to glow. These are old stars, on their way to becoming planetary nebulae. The Red Rectangle is an unusual example of what is known as a proto-planetary nebula. The high-resolution HST images reveal complex new structures, many of them unique to this. It consists of the equatorial rotating disk plus a spectacular axisymmetric nebula seen in the visible, surrounding a double stellar system (Menshchikov et al. It is likely that precessing jets of material played a role. planetary nebula associated with the post-AGB binary system HD 44179. Precisely how the central engine of this remarkable and unique object spun the gossamer threads of nebulosity remains mysterious. It also appears that the star is a close binary that is surrounded by a dense torus of dust - both of which may help to explain the very curious shape. The star at the centre is similar to the Sun, but at the end of its lifetime, pumping out gas and other material to make the nebula, and giving it the distinctive shape. ![]() Re-uploaded cropped to just a picture of the nebula. ![]() An excellent example of a bipolar nebula and a protoplanetary/planetary nebula. This strikingly detailed Hubble Space Telescope image reveals how, when seen from space, the nebula, rather than being rectangular, is shaped like an X with additional complex structures of spaced lines of glowing gas, a little like the rungs of a ladder. 22:15 Mgmirkin 583×584× (41821 bytes) Summary The Red Rectangle Nebula. It acquired its moniker because of its shape and its apparent colour when seen in early images from Earth. The reasons for these fresh periodic ejections of more gas and dust remain unknown.The star HD 44179 is surrounded by an extraordinary structure known as the Red Rectangle. The disc then funnels subsequent dust and gas outflows out along its axis, forming the bizarre bi-conical structure we see as the rung of the Red Rectangle. Interactions between these stars have probably caused the ejection of the thick dust disc that obscures our view of the binary. Astronomers have found that the central star is actually a close pair of stars orbiting each other with a period of about 10.5 months. The light we see streams out along the axis of the disc, and is scattered towards us by dust particles. ![]() This is the shadow of a dense disc of dust that surrounds the star and obscures it from direct view. Exactly which molecules in the dust cloud are responsible for the striking red colour of the Rectangle is not yet clear, but it is likely that they are some kind of hydrocarbon formed in the cool outflows from the central star.Īnother remarkable feature of the Red Rectangle, visible only with the superb resolution of the Hubble telescope, is the dark band passing across the central star. In a few thousand years, once the expulsion. Protoplanetary nebula are formed by old stars, on their way to becoming planetary nebulae. When this occurs the gas in the nebula will begin to fluoresce, producing a 'planetary nebula'.Īt the present time, however, the star is still so cool that atoms in the nebula do not glow and the surrounding dust particles are only visible as they reflect light from the central star. The Red Rectangle Nebula (HD 44179), so called because of its red color and unique rectangular shape, is a bipolar protoplanetary nebula, located about 2,300 light-years away toward the constellation Monoceros. The shedding of the outer layers began about 14 000 years ago, and in a few thousand years, the star will have become smaller and hotter, releasing a flood of ultraviolet light into the surrounding nebula. It is now nearing the end of its lifetime, and is in the process of ejecting its outer layers to produce the visible nebula. Catalogued as HD 44179, this nebula is more commonly called the 'Red Rectangle' because of its unique shape and colour as seen with ground-based telescopes. The star at the centre of the Red Rectangle began its life as a star similar to our Sun. This image, taken with the NASA/ESA Hubble Space Telescope, reveals startling new details of one of the most unusual nebulae known in our galaxy. ![]()
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