The James Webb Space Telescope has given astronomers a brand new view inside NGC 1514, a cosmic cloud formed as a dying star begins to shed its outer layers into space.
NGC 1514 can be seen in the constellation Taurus and is about 1,500 lightyears from Earth.
- See more of the James Webb Space Telescope's latest images
It's an object known as a planetary nebula, which is formed during the final stages of a star's life, when it begins to vent material into space and forms a puffed-out shape.
NGC 1514 was first observed in the 1700s, but only now, with the power of the James Webb Space Telescope, have astronomers been given a good look inside it.
What Webb sees in NGC 1514
"Before Webb, we weren’t able to detect most of this material, let alone observe it so clearly," says Mike Ressler, a researcher and project scientist for Webb’s MIRI (Mid-Infrared Instrument) at NASA’s Jet Propulsion Laboratory in southern California.
Ressler discovered the rings around NGC 1514 in 2010 using an image of the nebula captured with NASA’s Wide-field Infrared Survey Explorer (WISE), seen in the left image above.
"With MIRI’s data, we can now comprehensively examine the turbulent nature of this nebula."
These rings are revealed in infrared light and, while they look like defined structures in the WISE image, Webb has been able to resolve their clumpy, tangled nature.
Webb's view also reveals a network of clearer holes closer to the centre, which is where fast-moving ejected material has punched through.
Not one stars, but two
In images of NGC 1514, it may look like there's just one star, but there are actually two.
These binary stars orbit one another every 9 years. One of the stars used to be several times more massive than our Sun, and it's the one responsible for producing the planetary nebula.
The nebula has been forming for about 4,000 years.
“As the star evolved, it puffed up, throwing off layers of gas and dust in in a very slow, dense stellar wind," says David Jones, a senior scientist at the Institute of Astrophysics on the Canary Islands.
Once the star’s outer layers were shed into space, a hot, dense stellar core remained.
This stellar core – a 'white dwarf' – gives off a stream of charged particles known as 'stellar wind', which sped up and weakened and may have been responsible for sweeping up the surrounding material into thin shells.
NGC 1514's strange shape
The Webb image only gives us one perspective of this 3D object, but astronomers say NGC 1514 is likely an hourglass shape with the ends lopped off.
They point to instances at the top left and bottom right, where the dust is orange and forms a shallow V-shape, as evidence of a "pinched waist".
"What might explain these contours? When this star was at its peak of losing material, the companion star could have gotten very, very close," Jones says.
"That interaction can lead to shapes that you wouldn’t expect. Instead of producing a sphere, this interaction might have formed these rings."
Other mysteries remain
Why are NGC 1514's rings so unevenly illuminated? They seem much more diffuse in the top right and bottom left.
"We think the rings are primarily made up of very small dust grains," Ressler says.
"When those grains are hit by ultraviolet light from the white dwarf star, they heat up ever so slightly, which we think makes them just warm enough to be detected by Webb in mid-infrared light."
Webb's observations also reveal oxygen at the nebula's pink centre.
Yet, no carbon or other complex versions of carbon have been detected, which astronomers say is unusual for a planetary nebula like this.
Perhaps the two orbiting stars have been churning up the ejected material so much that more complex molecules haven't had time to form.
