With NASA’s Webb, Dying Star’s Energetic Display Comes Into Full Focus

Gas and dust ejected by a dying star at the heart of NGC 1514 came into complete focus thanks to mid-infrared data from NASA’s James Webb Space Telescope. Its rings, which are only detected in infrared light, now look like “fuzzy” clumps arranged in tangled patterns, and a network of clearer holes close to the central stars shows where faster material punched through.

“Before Webb, we weren’t able to detect most of this material, let alone observe it so clearly,” said Mike Ressler, a researcher and project scientist for Webb’s MIRI (Mid-Infrared Instrument) at NASA’s Jet Propulsion Laboratory in Southern California. He discovered the rings around NGC 1514 in 2010 when he examined the image from NASA’s Wide-field Infrared Survey Explorer (WISE). “With MIRI’s data, we can now comprehensively examine the turbulent nature of this nebula,” he said.

This scene has been forming for at least 4,000 years — and will continue to change over many more millennia. At the center are two stars that appear as one in Webb’s observation, and are set off with brilliant diffraction spikes. The stars follow a tight, elongated nine-year orbit and are draped in an arc of dust represented in orange.

One of these stars, which used to be several times more massive than our Sun, took the lead role in producing this scene. “As it evolved, it puffed up, throwing off layers of gas and dust in in a very slow, dense stellar wind,” said David Jones, a senior scientist at the Institute of Astrophysics on the Canary Islands, who proved there is a binary star system at the center in 2017.

Once the star’s outer layers were expelled, only its hot, compact core remained. As a white dwarf star, its winds both sped up and weakened, which might have swept up material into thin shells.

Its Hourglass Shape

Webb’s observations show the nebula is tilted at a 60-degree angle, which makes it look like a can is being poured, but it’s far more likely that NGC 1514 takes the shape of an hourglass with the ends lopped off. Look for hints of its pinched waist near top left and bottom right, where the dust is orange and drifts into shallow V-shapes.

What might explain these contours? “When this star was at its peak of losing material, the companion could have gotten very, very close,” Jones said. “That interaction can lead to shapes that you wouldn’t expect. Instead of producing a sphere, this interaction might have formed these rings.”

Though the outline of NGC 1514 is clearest, the hourglass also has “sides” that are part of its three-dimensional shape. Look for the dim, semi-transparent orange clouds between its rings that give the nebula body.

A Network of Dappled Structures

The nebula’s two rings are unevenly illuminated in Webb’s observations, appearing more diffuse at bottom left and top right. They also look fuzzy, or textured. “We think the rings are primarily made up of very small dust grains,” Ressler said. “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.”

In addition to dust, the telescope also revealed oxygen in its clumpy pink center, particularly at the edges of the bubbles or holes.

NGC 1514 is also notable for what is absent. Carbon and more complex versions of it, smoke-like material known as polycyclic aromatic hydrocarbons, are common in planetary nebulae (expanding shells of glowing gas expelled by stars late in their lives). Neither were detected in NGC 1514. More complex molecules might not have had time to form due to the orbit of the two central stars, which mixed up the ejected material. A simpler composition also means that the light from both stars reaches much farther, which is why we see the faint, cloud-like rings.

What about the bright blue star to the lower left with slightly smaller diffraction spikes than the central stars? It’s not part of this nebula. In fact, this star lies closer to us.

This planetary nebula has been studied by astronomers since the late 1700s. Astronomer William Herschel noted in 1790 that NGC 1514 was the first deep sky object to appear genuinely cloudy — he could not resolve what he saw into individual stars within a cluster, like other objects he cataloged. With Webb, our view is considerably clearer.

NGC 1514 lies in the Taurus constellation approximately 1,500 light-years from Earth.

More About Webb and MIRI

The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

MIRI was developed through a 50-50 partnership between NASA and ESA. A division of Caltech in Pasadena, California, the Jet Propulsion Laboratory led the U.S. contribution to MIRI. JPL also led development of MIRI’s cryocooler, done in collaboration with Northrop Grumman in Redondo Beach, California, and NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

To learn more about Webb, visit:

https://science.nasa.gov/webb