![]() The Helix Nebula was the first planetary nebula discovered to contain cometary knots. Spectroscopically, the outer ring's expansion rate is 40 km We see the outer-most ring as flattened on one side due to its colliding with the ambient interstellar medium.Įxpansion of the whole planetary nebula structure is estimated to have occurred in the last 6,560 years, and 12,100 years for the inner disk. ![]() The size of the inner disk is 8×19 arcmin in diameter (0.52 pc) the outer torus is 12×22 arcmin in diameter (0.77 pc) and the outer-most ring is about 25 arcmin in diameter (1.76 pc). The Helix Nebula is thought to be shaped like a prolate spheroid with strong density concentrations toward the filled disk along the equatorial plane, whose major axis is inclined about 21° to 37° from our vantage point. Recent images by the Hubble Space Telescope of the Helix Nebula are a composite of newly released images from the ACS instrument and the wide-angle images from the Mosaic Camera on the WIYN 0.9-metre telescope at Kitt Peak National Observatory.Ĭurrently, the age is estimated to be Template:Val years, based solely upon a measured expansion rate of 31 km ![]() The Helix Nebula in the constellation of Aquarius lies about 700 light-years away, spanning about 0.8 parsecs (2.5 light-years). The observed glow of the central star is so energetic that it causes the previously expelled gases to brightly fluoresce. The remnant central stellar core, known as a planetary nebula nucleus or PNN, is destined to become a white dwarf star. Gases from the star in the surrounding space appear, from our vantage point, as if we are looking down a helix structure. ![]() The Helix Nebula is an example of a planetary nebula, or 'planetary' formed at the end of a star's evolution. The Helix Nebula has sometimes been referred to as the "Eye of God" in pop culture, as well as the " Eye of Sauron". It is similar in appearance to the Cat's Eye Nebula and the Ring Nebula, whose size, age, and physical characteristics are similar to the Dumbbell Nebula, varying only in its relative proximity and the appearance from the equatorial viewing angle. The estimated distance is about 215 parsecs (700 light-years). Discovered by Karl Ludwig Harding, probably before 1824, this object is one of the closest to the Earth of all the bright planetary nebulae. The Helix Nebula, also known as The Helix, NGC 7293, is a large planetary nebula (PN) located in the constellation Aquarius. So depending on what wavelengths you observe it in, you get a different image. In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies.Image captured by the Hubble Space Telescope NGC 7293 in infrared by Hubble.īut why are all these pictures of the nebula different? Well, this glow ranges across a very broad part of the spectrum, from ultraviolet to infrared. The mass is so dense that about 1/10th of a tea spoon weighs more than you. White dwarfs are about as big as the Earth, but they still have most of their original mass. Eventually, the helium will also be exhausted and then you’re left with a small, yet still hot and very dense core called a white dwarf. When the hydrogen fuel for the fusion reaction runs out, the star turns to helium for a fuel source, burning it into an even heavier mix of carbon, nitrogen and oxygen. Also known by the catalog number NGC 7293, it is a typical example of a class of objects called planetary nebulae, and it’s one of the closes nebulas to Earth. It lies 650 light-years away, in the constellation of Aquarius. It’s estimated that our Sun will also become a nebula in about 5 billion years. The Helix Nebula used to be a star much like our Sun, but it is now in a different stage – ejecting most of its material.
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