Hubble offers a dazzling 'necklace'

Hubble offers a dazzling 'necklace'
The Necklace Nebula is located 15,000 light-years away in the constellation Sagitta (the Arrow). In this composite image, taken on July 2, 2011, Hubble's Wide Field Camera 3 captured the glow of hydrogen (blue), oxygen (green), and nitrogen (red). Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

( -- A giant cosmic necklace glows brightly in this NASA Hubble Space Telescope image.

The object, aptly named the Necklace Nebula, is a recently discovered , the glowing remains of an ordinary, Sun-like star. The nebula consists of a bright ring, measuring 12 trillion miles wide, dotted with dense, bright knots of gas that resemble in a necklace.

A pair of stars orbiting close together produced the nebula, also called PN G054.2-03.4. About 10,000 years ago one of the aging stars ballooned to the point where it engulfed its companion star. The smaller star continued orbiting inside its larger companion, increasing the giant’s rotation rate.

The bloated spun so fast that a large part of its gaseous envelope expanded into space. Due to centrifugal force, most of the gas escaped along the star’s equator, producing a ring. The embedded bright knots are dense gas clumps in the ring.

The pair is so close, only a few million miles apart, they appear as one bright dot in the center. The stars are furiously whirling around each other, completing an orbit in a little more than a day.

The Necklace Nebula is located 15,000 light-years away in the constellation Sagitta. In this composite image, taken on July 2, Hubble’s Wide Field Camera 3 captured the glow of hydrogen (blue), oxygen (green), and nitrogen (red).

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Aug 11, 2011
Looks more like a space opal, imho.

Aug 11, 2011
This reminds me of a song I wrote about 10 years ago, which talks about looking up into the night sky and seeing a necklace of stars.

Aug 11, 2011
Unfortunately this cropped image does not show off the full beauty (or extent) of this small planetary. A wider-field, annotated HST image shows two reddish patches of [NII] emission near the picture edges at 2 and 7 o'clock. You can check it out here: http://imgsrc.hub...rint.jpg

Examples of "ansae' such as these are not uncommon in some subtypes of planetary nebula

Aug 12, 2011
A paper on this unusual planetary nebula notes that there are both polar and equatorial outflows from the central binary pair. The secondary star, orbiting at 4-6 solar radii from the central star every 1.16 days is strongly irradiated on it's illuminated side, and this light dominates the observed spectrum. No mass transfer is seen between the two stars at this time. Details and more images can be found here:

A wider-angle view from the Isaac Newton Telescope can be found here: http://upload.wik.../IP6.jpg

Aug 12, 2011
Broken link there Ven...

Aug 13, 2011
This reminds me of the material around the equator in the fragmented remains of SN1987A.

Fragmentation - driven by neutron repulsion [1] - powers the cosmos, sustains our lives, and causes expansion of the universe as neutrons expand their volume by a factor of 10^15 (1,0000,000,000,000,000) in decaying into hydrogen atoms [2].

1. "Neutron Repulsion", The APEIRON Journal, in press, 19 pages (2011):

2. "Is the Universe Expanding?" The Journal of Cosmology 13, 4187-4190 (2011):


With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo

Aug 13, 2011
Hubble dazzling 'necklace'

Simply confirms that the Great Reality that surrounds and sustains -

Universe, God, Cosmos, Higher Power

Is powered by neutron repulsion [1] (illustrated by resentments, anger and violence in the Hindu Goddess Kali [2]) in compressed material at the cores of atoms, stars and galaxies while the universe expands [3].

Oliver K. Manuel


1. See above:

2. Kali: www.exoticindiaar...kali.htm

3. See above: http://journalofc...102.html

Aug 14, 2011
"This reminds me of the material around the equator in the fragmented remains of SN1987A.

Superficially the two rings do look similar. Even the secondary extraplanar rings share some similarities. Compare SN 1987A:

with a deep, wide-field view of the Necklace Nebula: http://upload.wik.../IP6.jpg

Morphology aside, the bright EQ ring in SN1987A is the result of material expelled by the SN that is just now crashing into this much older ring.

In the case of the Necklace, strong UV from the freshly-exposed core irradiates the gasses in the ring.

According to the paper I've linked above, the mass of the hot post-AGB primary star ~0.5-1.0 solar masses while the secondary is estimated to be no more than 1 solar mass. Thus neither star was massive enough to go SN to begin with (and any earlier mass transfer was apparently insufficient to bring this about either). So no pulsar progenitor too!

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