Related topics: stars · white dwarfs · hubble space telescope

Stunning new Hubble images reveal stars gone haywire

The NASA/ESA Hubble Space Telescope demonstrates its full range of imaging capabilities with two new images of planetary nebulae. The images depict two nearby young planetary nebulae, NGC 6302, dubbed the Butterfly Nebula, ...

Hubble detects giant 'cannonballs' shooting from star

Great balls of fire! NASA's Hubble Space Telescope has detected superhot blobs of gas, each twice as massive as the planet Mars, being ejected near a dying star. The plasma balls are zooming so fast through space it would ...

Mysteries behind interstellar buckyballs finally answered

Scientists have long been puzzled by the existence of so-called "buckyballs"—complex carbon molecules with a soccer-ball-like structure—throughout interstellar space. Now, a team of researchers from the University of ...

What will happen when our sun dies?

Scientists agree the sun will die in approximately 10 billion years, but they weren't sure what would happen next... until now.

NGC 2392: A beautiful end to a star's life

(Phys.org) —Stars like the Sun can become remarkably photogenic at the end of their life. A good example is NGC 2392, which is located about 4,200 light years from Earth. NGC 2392, (nicknamed the "Eskimo Nebula") is what ...

Manchester astronomers detect precious element in space

A team of astronomers from The University of Manchester, together with collaborators from the Centro de Astrobiología and the Deep Space Network, Spain and the Universidad Nacional Autónoma de México, have detected a rare ...

Hubble captures brilliant star death in 'rotten egg' nebula

The Calabash Nebula, pictured here—which has the technical name OH 231.8+04.2—is a spectacular example of the death of a low-mass star like the sun. This image taken by the NASA/ESA Hubble Space Telescope shows the star ...

Hubble finds stellar life and death in a globular cluster

(PhysOrg.com) -- A new NASA Hubble Space Telescope image shows globular cluster NGC 1846, a spherical collection of hundreds of thousands of stars in the outer halo of the Large Magellanic Cloud, a neighboring dwarf galaxy ...

Image: Hubble sees a dying star's final moments

A dying star's final moments are captured in this image from the NASA/ESA Hubble Space Telescope. The death throes of this star may only last mere moments on a cosmological timescale, but this star's demise is still quite ...

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Planetary nebula

A planetary nebula is an emission nebula consisting of a glowing shell of gas and plasma formed by certain types of stars when they die. The name originated in the 18th century because of their similarity in appearance to giant planets when viewed through small optical telescopes, and is unrelated to the planets of the solar system. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years.

At the end of the star's life, during the red giant phase, the outer layers of the star are expelled via pulsations and strong stellar winds. Without these opaque layers, the remaining core of the star shines brightly and is very hot. The ultraviolet radiation emitted by this core ionises the ejected outer layers of the star which radiate as a planetary nebula.

Planetary nebulae are important objects in astronomy because they play a crucial role in the chemical evolution of the galaxy, returning material to the interstellar medium which has been enriched in heavy elements and other products of nucleosynthesis (such as carbon, nitrogen, oxygen and calcium). In other galaxies, planetary nebulae may be the only objects observable enough to yield useful information about chemical abundances.

In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies. About a fifth are roughly spherical, but the majority are not spherically symmetric. The mechanisms which produce such a wide variety of shapes and features are not yet well understood, but binary central stars, stellar winds and magnetic fields may all play a role.

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