Latest Planetary nebula Stories

2009-12-07 07:30:00

Astronomers facing Socratic "ignorance" An extensive study made with ESO's Very Large Telescope deepens a long-standing mystery in the study of stars similar to the Sun. Unusual year-long variations in the brightness of about one third of all Sun-like stars during the latter stages of their lives still remain unexplained. Over the past few decades, astronomers have offered many possible explanations, but the new, painstaking observations contradict them all and only deepen the mystery. The...

2009-08-14 07:35:00

A team of scientists in Australia and the United States, led by Associate Professor Miroslav FilipoviÄ“¡ from the University of Western Sydney, have discovered a new class of object which they call "Super Planetary Nebulae."  They report their work in the journal Monthly Notices of the Royal Astronomical Society. Planetary nebulae are shells of gas and dust expelled by stars near the end of their lives and are typically seen around stars comparable or smaller in...

2009-07-20 15:45:00

A star does not die without getting noticed and may even leave the universe with "fireworks." At the end of its life cycle, a star begins to collapse in the middle and throws new material into space. The new material eventually becomes incorporated into new planets and life. Now, a University of Missouri professor identified new features in the material that is being ejected from the dying star Helix Nebula. A high-resolution near-infrared image revealed new information about the knots, or...

2009-05-20 09:45:00

Using ESO's Very Large Telescope, astronomers have succeeded in measuring the size of giant galaxy Messier 87 and were surprised to find that its outer parts have been stripped away by still unknown effects. The galaxy also appears to be on a collision course with another giant galaxy in this very dynamic cluster. The new observations reveal that Messier 87's halo of stars has been cut short, with a diameter of about a million light-years, significantly smaller than expected, despite being...

2009-05-10 13:35:00

The Hubble community bids farewell to the soon-to-be decommissioned Wide Field and Planetary Camera 2 onboard NASA's Hubble Space Telescope. In tribute to Hubble's longest-running optical camera, which was developed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif., a planetary nebula has been imaged as the camera's final "pretty picture." This planetary nebula is known as Kohoutek 4-55 (or K 4-55). It is one of a series of planetary nebulae that were named after their...

2009-05-06 07:05:00

Designed and built by JPL, the Wide Field and Planetary Camera 2 has been the workhorse camera on NASA's Hubble Space telescope's since it was added to the observatory in December of 1993. The camera has produced most of the stunning images that have been released by Hubble during its 15-plus years of service. Its high image resolution and quality are some of the reasons the camera became the space telescope's most requested instrument. Throughout history, humanity has been moved by the work...

2009-03-12 12:40:00

The "Cat's Eye" nebula, or NGC 6543, is a well-studied example of a "planetary nebula." Such objects are the glowing remnants of dust and gas expelled from moderate-sized stars during their last stages of life. Our own sun will generate such a nebula in about five billion years. NASA's Spitzer Space Telescope has studied many such planetary nebulae in infrared light, including a variety of more distant ones, which have helped scientists identify a population of carbon-bearing stars near our...

2009-02-25 08:15:00

A deep new image of the magnificent Helix planetary nebula has been obtained using the Wide Field Imager at ESO's La Silla Observatory. The image shows a rich background of distant galaxies, usually not seen in other images of this object. The Helix Nebula, NGC 7293, lies about 700 light-years away in the constellation of Aquarius (the Water Bearer). It is one of the closest and most spectacular examples of a planetary nebula. These exotic objects have nothing to do with planets, but are the...

2009-01-07 12:55:00

Even some stars go ballistic, racing through interstellar space like bullets and tearing through clouds of gas. Images from NASA's Hubble Space Telescope reveal 14 young, runaway stars plowing through regions of dense interstellar gas, creating brilliant arrowhead structures and trailing tails of glowing gas. These arrowheads, or bow shocks, form when the stars' powerful stellar winds, streams of matter flowing from the stars, slam into surrounding dense gas. The phenomenon is similar to that...

2008-11-19 14:18:57

The explosion of a binary star inside a planetary nebula has been captured by a team led by UCL (University College London) researchers "“ an event that has not been witnessed for more than 100 years. The study, published in Astrophysical Journal Letters, predicts that the combined mass of the two stars in the system may be high enough for the stars to eventually spiral into each other, triggering a much bigger supernova explosion. Dr Roger Wesson, UCL Physics and Astronomy, says: "At...

Latest Planetary nebula Reference Libraries

2004-10-19 04:45:42

Star -- A star is a self-gravitating sphere of plasma in hydrostatic equilibrium that generates energy in its interior through the process of nuclear fusion. Energy from this process radiates into space as electromagnetic radiation and neutrinos. Star formation and evolution As learned by star formation astronomers, stars are born in molecular clouds, regions of higher density of matter, and form by gravitational instability inside those clouds. High mass stars illuminate powerfully...

2004-10-19 04:45:42

Planetary Nebula -- A planetary nebula is an astronomical object that usually appears nebulous and disk-like in low-resolution observations. Because of this appearance, similar to the appearance of planets in early observations, the "planetary" adjective was attached and has since been retained for historical consistency. According to current observations and models, planetary nebulae in fact have little to do with planets. Instead, as a small star (less than a few times the mass...

2004-10-19 04:45:42

Nebula -- in astronomy, observed manifestation of a collection of highly rarefied gas and dust in interstellar space. Prior to the 1960s this term was also applied to bodies later discovered to be galaxies, e.g., the so-called Great Nebula in the constellation Andromeda. In 1864, William Huggins confirmed William Herschel's conclusion that nebulae are not swarms of stars by determining that the spectra of nebulae are made of bright lines characteristic of radiating gases. Diffuse...

2004-10-19 04:45:40

Saturn Nebula -- The layers of the Saturn Nebula give a complex picture of how this planetary nebula was created. The above picture, taken in April 1996 and released last week, allows a better understanding of the mysterious process that transformed a low-mass star into a white dwarf star. A computer model indicates that the central star of NGC 7009 first expelled the green gas that now appears barrel shaped. This green gas now confines stellar winds flowing from the central star,...

2004-10-19 04:45:40

Ring Nebula -- Discovered by Antoine Darquier de Pellepoix in 1779. The famous ring nebula M57 is often regarded as the prototype of a planetary nebula, and a showpiece in the northern hemisphere summer sky. Recent research has confirmed that it is, most probably, actually a ring (torus) of bright light-emitting material surrounding its central star, and not a spherical (or ellipsoidal) shell, thus coinciding with an early assumption by John Herschel. Viewed from this equatorial...

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  • A blustering, bullying fellow; a pot-valiant braggart; a bully.
This word is named for Draw-Can-Sir, a character in George Villiers' 17th century play The Rehearsal.