Extract from ABC News
The ultra-powerful James Webb Space Telescope has done it again, this time producing ethereal imagery of a star's death.
A team of astronomers at the University of Manchester used the telescope to capture images of the iconic Ring Nebula, which is approximately 2,600 light-years from earth.
What is a nebula?
A nebula is a giant cloud of dust and gas floating in space.
Some nebulae indicate regions where new stars are beginning to form.
Others come from the gas and dust throw out by the explosion of a dying star.
What is the Ring Nebula?
The glowing remains of a Sun-like star.
It's known as the Ring Nebula for its distinct circular pattern, but it also goes by the more scientific name Messier 57.
It was discovered in 1779 by French astronomer Antoine Darquier de Pellepoix.
University of Manchester researchers estimate it formed about 4,000 years ago when layers of gas were ejected into space, leaving behind the star's hot core — which experts call a white dwarf.
Messier 57's white dwarf is visible as a small white dot in the new images:
Surrounding the white dwarf are layers of dust and gas, giving the appearance of stacked rings.
And while these images were produced using a very powerful telescope, you can see the Ring Nebula from Earth.
A small telescope pointed at the right spot in the Lyra constellation will reveal its trademark donut-like structure.
What's great about it Messier 57 is that it's tilted towards Earth face-on, giving us clear full images of the nebula.
The timing for the release of this JWST's image is great — because NASA says the Ring Nebula is best observed during August.
Is Messier 57 really bright purple and green?
Sorry to burst your bubble, but Messier 57 looks different to the human eye.
In fact, the image above is actually a series of separate exposures that were originally in greyscale and were beamed back to Earth.
They were taken using JWST's Near infrared Camera (NIRCam), which covers infrared wavelength range from 0.6 to 5 microns.
The equipment allows astronomers to take pictures of very faint objects around a central bright object, a NASA fact sheet says.
It works by blocking out the brighter object's light, which makes it possible to capture the dimmer object nearby.
These images are layered on top of each other and colourised to make the final brilliant images.
For example, the most recent James Webb images of Messier 57 were created with three different filters:
- F212N (blue)
- F300M (green)
- F335M (red)
Here's another image of Messier 57 from 2017.
It was taken using the Hubble Telescope and was colourised to illustrate the nebula's chemical composition.
The deep blue colour in the centre represents helium, while the light blue colour of the inner ring is the glow of hydrogen and oxygen.
The reddish colour of the outer ring is from nitrogen and sulfur.
But it's not all about bright colours
University of Manchester astronomers are in awe of these new high-definition images because they present a new opportunity to research the nebula's complex structure.
"The high-resolution images not only showcase the intricate details of the nebula's expanding shell but also reveal the inner region around the central white dwarf in exquisite clarity," said James Webb Space Telescope Ring Nebula Project lead scientist Mike Barlow.
"We are witnessing the final chapters of a star's life, a preview of the Sun’s distant future so to speak."
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