Category: nebulosa

Flight Through Orion Featuring Four Nabulae …

Flight Through Orion Featuring Four Nabulae and Two Flash Illuminated Engines – Aug 5, 2007.

Image Credit:

Joseph Brimacombe

The NASA/ESA Hubble Space Telescope captures…

The NASA/ESA Hubble Space Telescope captures the iridescent tapestry of star birth in a neighbouring galaxy in this panoramic view of glowing gas, dark dust clouds, and young, hot stars.

Credit: NASA/ESA and the Hubble Heritage Team (AURA/STScI/HEIC)

Hubble has taken this stunning close-up shot o…

Hubble has taken this stunning close-up shot of part of the Tarantula Nebula. This star-forming region of ionised hydrogen gas is in the Large Magellanic Cloud, a small galaxy which neighbours the Milky Way. It is home to many extreme conditions including supernova remnants and the heaviest star ever found. The Tarantula Nebula is the most luminous nebula of its type  in the local Universe.

Credit: NASA, ESA

Pelican Nebula by Roberto Colombari

Pelican Nebula

by

Roberto Colombari

Planetary Nebulae: Cat’s Eye Nebula &amp…

Planetary Nebulae: Cat’s Eye Nebula & Eskimo Nebula 

Our solar system will also have a planetary nebula. In about 5 billion years, when the sun comes loose from its outer layers, it will create a beautiful diffuse shell of gas.

Image credit: NASA

/ESA, Hubble

What’s Your favorite space object?

What’s Your favorite space object?

Planetary nebula A planetary nebula, abbrev…

Planetary nebula

A planetary nebula, abbreviated as PN or plural PNe, is a kind of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The word “nebula” is Latin for mist or cloud, and the term “planetary nebula” is a misnomer that originated in the 1780s with astronomer William Herschel because, when viewed through his telescope, these objects resemble the rounded shapes of planets. Herschel’s name for these objects was popularly adopted and has not been changed. 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.

Most planetary nebulae form at the end of the star’s life, during the red giant phase, when the outer layers of the star are expelled by strong stellar winds. After most of the red giant’s atmosphere is dissipated, the ultraviolet radiation of the hot luminous core, called a planetary nebula nucleus (PNN), ionizes the ejected material. Absorbed ultraviolet light energises the shell of nebulous gas around the central star, causing it to appear as a brightly coloured planetary nebula.

Planetary nebulae likely play a crucial role in the chemical evolution of the Milky Way by expelling elements to the interstellar medium from stars where those elements were created. Planetary nebulae are observed in more distant galaxies, yielding useful information about their chemical abundances.

Stars greater than 8 solar masses (M) will likely end their lives in dramatic supernovae explosions, while planetary nebulae seemingly only occur at the end of the lives of intermediate and low mass stars between 0.8 M to 8.0 M.

  • source 
  • images: NASA/ESA, Hubble

The Crab Pulsar (PSR B0531+21) is a relative…

The Crab Pulsar (PSR B0531+21) is a relatively young neutron star. The star is the central star in the Crab Nebula, a remnant of the supernova SN 1054, which was widely observed on Earth in the year 1054. Discovered in 1968, the pulsar was the first to be connected with a supernova remnant.

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The Crab Pulsar is one of very few pulsars to be identified optically. The optical pulsar is roughly 20 kilometres (12 mi) in diameter and the pulsar “beams” rotate once every 33 milliseconds, or 30 times each second.

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The outflowing relativistic wind from the neutron star generates synchrotron emission, which produces the bulk of the emission from the nebula, seen from radio wavesthrough to gamma rays. The most dynamic feature in the inner part of the nebula is the point where the pulsar’s equatorial wind slams into the surrounding nebula, forming a termination shock.

The shape and position of this feature shifts rapidly, with the equatorial wind appearing as a series of wisp-like features that steepen, brighten, then fade as they move away from the pulsar into the main body of the nebula. The period of the pulsar’s rotation is slowing by 38 nanoseconds per day due to the large amounts of energy carried away in the pulsar wind.

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The Crab Nebula is often used as a calibration source in X-ray astronomy. It is very bright in X-rays and the flux density and spectrum are known to be constant, with the exception of the pulsar itself.

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A History of the Crab Nebula

images: NASA/ESA, Hubble, Cambridge University Lucky Imaging Group, 

NASA/CXC/ASU/J.Hester et al.

Star-forming region RCW 108 in Ara. RCW 108…

Star-forming region RCW 108 in Ara.

RCW 108 is a molecular cloud that is in the process of being destroyed by intense ultraviolet radiation from heavy and hot stars in the nearby stellar cluster NGC 6193, seen to the left in the photo. 

Credit: ESO

Located in the Southern Hemisphere, NGC 3324…

Located in the Southern Hemisphere, NGC 3324 is at the northwest corner of the Carina Nebula (NGC 3372), home of the Keyhole Nebula and the active, outbursting star Eta Carinae. The entire Carina Nebula complex is located at a distance of roughly 7,200 light-years, and lies in the constellation Carina.

Image credit: NASA/ESA/Hubble