Hubble Captures Cat's Eye Nebula
Like an onion cut in half, the concentric shells surrounding the Cat's Eye Nebula are visible in the newest image from the Hubble Space Telescope. Shells around planetary nebulae were thought to be rare occurrences. But, in a paper published in the European journal Astronomy & Astrophysics earlier this year, it was shown that such rings are found in at least a third of all planetary nebula, and so are probably more common than not, according to a NASA press release.
Picture: ESA/NASA/HEIC/The Hubble Heritage Team (STScI/AURA)
Hubble's Image of the Cat's Eye Nebula
This view from the Hubble Space Telescope captures the Cat's Eye Nebula. Although the Cat's Eye Nebula was one of the first planetary nebulae ever to be discovered, it remains one of the most complex and least understood.
Planetary nebulae form when sun-like stars gently eject their outer gaseous layers.
The rings are thought appear every 1,500 years or so, when a star ejects its mass in a cosmic belch that creates dust shells containing as much mass as all of the planets in the solar system, according to the press release.
The new Hubble image reveals that each ring is actually the edge of a bubble projected onto the sky, which is why is seems bright along its outer edge, the press release said.
The rings might contain the secret to how the central star of the nebula dies, but the Cat's Eye Nebula's Russian doll-like structure remains a mystery to astronomers.
Pictures: Nordic Optical Telescope/Romano Corradi |
Gaseous Halo
An enormous, but extremely faint, halo of gaseous material surrounds the Cat's Eye Nebula. Within the past years some planetary nebulae been found to have halos like this one, likely formed of material ejected during earlier active episodes in the star's evolution.
The Cat's Eye Nebula was among the first planetary nebulae ever discovered and is one of the most complex.
Meanwhile, in early August NASA engineers got the thumbs up to start planning a robotic mission to repair Hubble, which lost the use of a key instrument. The mission, planned for around three years from now, will also install two new instruments — a sophisticated camera and a spectrograph.
Re: Hubble Captures Cat's Eye Nebula
Re: Hubble Captures Cat's Eye Nebula