The James Webb Space Telescope has revealed new details in the core of the Butterfly Nebula, known to astronomers as NGC 6302. From the dense ring of dust that surrounds the nebula’s core to the tiny but bright star hidden within, the Webb observations paint a never-before-seen portrait of the nebula’s inner workings. The new imagery also helps scientists understand the origins of comic dust.

“Most of the material in rocks, gems, bones — really the Earth itself — arrived here as a cloud of tiny cosmic dust particles. Rocky planets are made of this stuff,” said , a 91̽��professor emeritus of astronomy and a member of the research team. “The Butterfly Nebula is one of the nearest prolific sources of fresh cosmic dust, so it’s a great place to study how dust forms and disperses.”

The results in Monthly Notices of the Royal Astronomical Society. The Webb telescope team on its mission website.

Planetary nebulae form when stars with masses between about 0.8 and eight times that of the sun shed most of their mass at the end of their lives, generating huge outbursts of gas and dust. The Butterfly Nebula, located about 3,400 light-years away in the constellation, is one of the best-studied planetary nebulae in our galaxy and was. It belongs to a class of bipolar nebulae, meaning that it has two lobes of dust and gas that spread out in opposite directions from the central star, forming the “wings” of the butterfly. The torus-shaped cloud of dust and gas poses as the butterfly’s “body” and obscures the star that created it.

The new Webb imagery zooms in on the center of the Butterfly Nebula and its dusty ring. The telescope’s uniquely powerful Mid-InfraRed Instrument, or , analyzed the chemical makeup of the dust and also peered through it, revealing the hidden star at the core. This Earth-sized star is tiny but over 1,000 times brighter than the sun, and at 222,000 Kelvin is one of the hottest known central stars in any planetary nebula.

Webb’s observations also revealed familiar materials in this exotic locale. The new data show that the dust ring is composed partly of crystalline silicates like quartz, which are common in rocks here on Earth. The team also spotted a class of organic molecules known as polycyclic aromatic hydrocarbons, or PAHs, which turn up in campfire smoke and burnt toast. This may be the first-ever evidence of PAHs forming in a planetary nebula, providing important clues to these molecules’ origin.

For researchers like Balick, getting a good look at both the central star and the dust it produced is key.

“Billions of long-gone stars, once similar to the newly discovered star that produced the Butterfly, created important raw materials like carbon-based organic molecules and silicates that condensed to make the Earth’s first surface,” Balick said. “The Butterfly enables us to look into the very start of this process.”

Contrary to the name, planetary nebulae have nothing to do with planets: The naming confusion began several hundred years ago, when astronomers reported that the first nebulae they found appeared round, like planets. The name stuck, even though many planetary nebulae aren’t round at all — the Butterfly Nebula itself is a prime example of the unusual and mysterious shapes that they can take.

“When I saw the new images, I realized there’s still a lot to learn about the formation and shaping of planetary nebulae — more than we ever anticipated,” Balick said. “But that’s how science works. You peel the onion one layer at a time.”

A full list of co-authors is included with the .��

This research was funded by NASA and the European Space Agency (ESA), who funded the James Webb Space Telescope and its scientific instruments, as well as individual research grants from the teams’ home countries.

For more information, contact Balick at balick@uw.edu.

This story was adapted from by NASA and ESA. See from the Royal Astronomical Society.

Planetary nebulae form when red giant stars expel their outermost layers as they run out of helium fuel — becoming hot, dense white dwarf stars that are roughly the size of Earth. The material that was shed, enriched in carbon, forms dazzling patterns as it is blown gently into the interstellar medium.

Most planetary nebulae are roughly circular, but a few have an hourglass or wing-like shape, like the aptly named “Butterfly Nebula.” These shapes are likely formed by the gravitational tug of a second star orbiting the nebula’s “parent” star, causing the material to expand into a pair of nebular lobes, or “wings.” Like an expanding balloon, the wings grow over time without changing their original shape.

Yet new research shows that something is amiss in the Butterfly Nebula. When a team led by astronomers at the 91̽�� compared two exposures of the Butterfly Nebula taken by the Hubble Space Telescope in 2009 and 2020, they saw dramatic changes in the material within the wings. As they reported on Jan. 12 at the in Seattle, powerful winds are driving complex alterations of material within the nebula’s wings. They want to understand how such activity is possible from what should be a “sputtering, largely moribund star with no remaining fuel.”

“The Butterfly Nebula is extreme for the mass, speed and complexity of its ejections from its central star, whose temperature is more than 200 times hotter than the sun yet is just slightly larger than the Earth,” said team leader Bruce Balick, a 91̽��professor emeritus of astronomy. “I’ve been comparing Hubble images for years and I’ve never seen anything quite like it.”

The team compared high-quality Hubble images taken 11 years apart to chart the speeds and growth patterns of features within the nebula’s wings. The bulk of the analysis was performed by Lars Borchert, a graduate student at Aarhus University in Denmark who participated in this study as a 91̽��undergraduate student.

Borchert discovered roughly half a dozen “jets” — beginning about 2,300 years ago and ending 900 years ago — pushing material out in a series of asymmetrical outflows. Material in the outer portions of the nebula is moving rapidly, at about 500 miles per second, while material closer to the hidden central star is expanding much more slowly, at about a tenth of that speed. Paths of the jets cross one another, forming “messy” structures and growth patterns within the wings.

The nebula’s multi-polar and swiftly changing interior structure is not easy to explain using existing models of how planetary nebulae form and evolve, according to Balick. The star at the center of the nebula, which is hidden by dust and debris, could have merged with a companion star or drew off material from a nearby star, creating complex magnetic fields and generating the jets.

“At this point, these are all just hypotheses,” said Balick. “What this shows us is that we don’t fully understand the full range of shaping processes at work when planetary nebulae form. The next step is to image the nebular center using the James Webb Space Telescope, since infrared light from the star can penetrate through the dust.”

Stars like our sun will swell into a red giant and form planetary nebulae someday, expelling carbon and other relatively heavy elements into the interstellar medium to form star systems and planets in the far future. This new research, and other “time-lapse” analyses of planetary nebulae, can help illustrate not just how the materials for the star systems of tomorrow will take shape, but also how the building blocks of our own oasis were produced and gathered billions of years ago.

“It’s a creation story that is happening over and over again in our universe,” said Balick. “The shaping processes provide key insight into the history and impacts of the stellar activity.”

Other team members are Joel Kastner of the Rochester Institute of Technology and Adam Frank of the University of Rochester.

For more information, contact Balick at balick@uw.edu.

Planetary nebulae are shells of gas and dust shed by certain types of dying stars, mostly likely including the sun in another 6 billion years. New data from NASA’s James Webb Space Telescope is shedding light on how and why these nebulae form.

At center of one planetary nebula, the Southern Ring Nebula, just a single star is visible in optical images, such as those taken by the Hubble Space Telescope. But the JWST has revealed that this star was merely a passive bystander when the nebula formed. A team of almost 70 astronomers, including Bruce Balick, a 91̽�� professor of astronomy, used some of the first data from the new telescope to show that unseen companions shaped the intricate features of the nebula.

The source of the material in the Southern Ring Nebula is a tiny white dwarf star, as shown in some of the first JWST released earlier this year by NASA, according to Balick.

In a study published Dec. 8 in Nature Astronomy, an international research team, led by Orsola De Marco of Macquarie University in Sydney, Australia, analyzed 10 highly detailed exposures taken by the JWST of the Southern Ring Nebula. Their calculations show the central star that ejected the expanding nebula gas was originally three times the mass of the sun. Today, after the ejections, it measures about 60% of the mass of the sun.

“The James Webb Space Telescope is already shaping up to be a powerful — indeed game changing — new tool in the quiver of telescopes used to study dying stars like that at the center of the Southern Ring. It is following the impact of the Hubble Space Telescope launched over 30 years ago,” said Balick. “Studying the nebulae such as the Southern Ring with the Webb provides key insights for exploring how stars evolve and disperse matter into their surrounding environments.”

The JWST images revealed details of the faint material around the outermost edges of the Southern Ring Nebula. This material, made up largely of cold dust and molecules, was the first to be ejected by the dying star about 1,000 years ago. Analyzing its current shape will help scientists understand how the ejection process began.

“With Webb, it’s like we were handed a microscope to examine the universe,” said De Marco. “There is so much detail in its images. We approached our analysis much like forensic scientists to rebuild the scene.”

“The pattern of the light from this aboriginal gas is far more complex than we had any right to anticipate,” said Balick. “For the first time we were able to see many devils in the details. Each of those devils has a story to tell. There’s no doubt that my field of research — the strange throes of dying stars — has already been forever changed by what we learn from these Webb images.�� I am ecstatic at the scientific prospects of this new telescope. I should say ‘gobsmacked’!”

In order to explain the structure of the nebula revealed by the new images, the team has proposed that at least two close companion stars orbited the star at the center of the nebula as it shed its mass. During this intimate “dance,” the interacting stars may have launched two-sided , which appeared later as roughly paired projections that are now observed at the edges of the nebula.

“The gravity of these nearby orbiting stars extruded the newly ejected and outflowing gas into the complex nebula that we see today, much like taffy sold at carnivals,” said Balick.

Without those companion stars, the Southern Ring Nebula would likely be round and bubble-shaped like many other planetary nebulae.

“The [white dwarf] star is now smaller and hotter, but is surrounded by cool dust,” said co-author Joel Kastner at the Rochester Institute of Technology. “We think all that gas and dust we see thrown all over the place must have come from that one star, but it was tossed in very specific directions by the companion stars.”

Where are those companions now? They are either dim enough to hide, camouflaged by the bright lights of the two central stars, or have merged with the dying star.

In addition, a third, closely interacting star may have agitated the jets, skewing the evenly balanced ejections like spin art. And a fourth star with a slightly wider orbit might have “stirred the pot” of ejections, generating the enormous set of irregular rings in the outer reaches of the nebula.

“Sometimes I wish that the Earth were in orbit around the massive and optically visible star just off center in the Southern Ring Nebula since we would have front row seats to see the poorly understood mass ejection process,” said Balick. “Observing from the back bleachers 2,300 light years away may be safe, but it’s really frustrating.”

For more information, contact Balick at balick@uw.edu.  

Adapted from a by the Space Telescope Science Institute.

Stars are rather patient. They can live for billions of years, and they typically make slow transitions — sometimes over many millions of years — between the different stages of their lives.

So when a previously typical star’s behavior rapidly changes in a few decades, astronomers take note and get to work.

Such is the case with a star known as SAO 244567, which lies at the center of Hen 3-1357, commonly known as the Stingray Nebula. The Stingray Nebula is a planetary nebula — an expanse of material sloughed off from a star as it enters a new phase of old age and then heated by that same star into colorful displays that can last for up to a million years.

The tiny Stingray Nebula unexpectedly appeared in the 1980s and was using NASA’s Hubble Space Telescope. It is by far the youngest planetary nebula in our sky. A team of astronomers recently analyzed a more recent image of the nebula, taken in 2016 by Hubble, and found something unexpected: As they report in a paper accepted to the Astrophysical Journal, the Stingray Nebula has faded significantly and changed shape over the course of just 20 years.

If dimming continues at current rates, in 20 or 30 years the Stingray Nebula will be barely perceptible, and was likely already fading when Hubble obtained the first clear images of it in 1996, according to lead author , an emeritus professor of astronomy at UW.

“This is an unprecedented departure from typical behavior for a planetary nebula,” said Balick. “Over time, we would expect it to imperceptibly brighten and expand, which could easily go unnoticed in a century or more. But here we’re seeing the Stingray nebula fade significantly in an incredibly compressed time frame of just 20 years. Moreover, its brightest inner structure has contracted — not expanded — as the nebula fades.”

Planetary nebulae form after most stars, including stars like our own sun, swell into red giants as they exhaust hydrogen fuel. At the end of the red giant phase, the star then expels large amounts of its outer material as it gradually — over the course of a million years — transforms into a small, compact white dwarf. The sloughed-off material expands outward for several thousand years while the star heats the material, which eventually becomes ionized and glows.

Balick and his co-authors, Martín Guerrero at the Institute of Astrophysics of Andalusia in Spain and Gerardo Ramos-Larios at the University of Guadalajara in Mexico, compared Hubble images of the Stingray Nebula taken in 1996 and 2016. Hen 3-1357 changed shape markedly over 20 years, losing the sharp, sloping edges that gave the Stingray Nebula its name. Its colors have faded overall and once-prominent blue expanses of gas near its center are largely gone.

“In a planetary nebula, the star is really the center of all the activity,” said Balick. “The material around it is directly responsive to the energy from its parent star.”

The team analyzed light spectra from Hen 3-1357 emitted by chemical elements in the nebula. Emission levels of hydrogen, nitrogen, sulfur and oxygen all dropped between 1996 and 2016, particularly oxygen, which dropped by a factor of 900. The resulting fade in color and the nebula’s change in shape are likely connected to the cooling of its parent star — from a peak of about 107,500 degrees Fahrenheit in 2002 to just under 90,000 degrees Fahrenheit in 2015 — which means it is giving off less ultraviolet ionizing radiation that heats the expelled gas and makes it glow.

“Like a doused forest fire, the smoke wanes more slowly than the flames that created it,” said Balick. “Even so, we were amazed when the Hubble images revealed how quickly the nebula was fading. It took a month of work to believe it.”

Astronomers have yet to understand why SAO 244567 made the Stingray Nebula light up and then fade almost as quickly. One theory, posited by a team led by Nicole Reindl at the University of Potsdam, is that the star underwent a brief burst of fresh helium fusion around its core, which stirred up its outer layers and caused its surface to both shrink and heat.

If so, then as its outer layers settle back down, the star may return to a more typical transition from red giant to white dwarf. Only future observations of the star and its nebula can confirm this.

“Unfortunately, the best tool to follow future changes in the Stingray Nebula, the Hubble Space Telescope, is near the end of its life as well,” said Balick. “We can hope, but the odds aren’t good for Hubble’s survival as its three remaining gyroscopes start to fail. It’s a good race to the finish.”

The Hubble Space Telescope is an international partnership between NASA and the European Space Agency, or ESA, and managed by NASA’s Goddard Space Flight Center in Maryland. The Space Telescope Science Institute is responsible for Hubble science operations. The research was also funded by the European Union and the National Council of Science and Technology in Mexico.

For more information, contact Balick at balick@uw.edu.

With less than a week to go before the Pacific Northwest experiences its first total solar eclipse in decades, many in Seattle are wondering what it will be like in our city, where the moon will cover about 92 percent of the sun’s surface. , 91̽��professor emeritus of astronomy, shared a few thoughts that he’s written for the upcoming event.

What will happen next Monday?

Everyone will notice how dark the sky becomes starting at about 9:45 a.m. — it reaches its maximum at 10:22 a.m. You and everyone else will be tempted to run outside to observe the eclipse.

Whatever you do, don’t look up — at least not unless you are wearing certified-safe protection or taking proper precautions.

There is no safe time to stare at the exposed surface of the sun. Ever. It will be very tempting but highly dangerous to take a peek at any time without a safe means (see below). Never — never — view the partial eclipse through binoculars or a telescope.

What’s the danger? If you have ever fried bugs with a magnifying glass then you can imagine the damage to your retina if you look at any part of the sun directly. The eclipse simply isn’t worth a permanent blind spot.

What to expect in Seattle: 

The sun will appear as a shining fingernail when the eclipse is at its maximum (95 percent).

Be sure to look around you during maximum eclipse. The birds will roost as the sky darkens, sleep for a few moments, and then get up and start their next day. The horizon will glow all around you, roughly like sunset. You may attempt a brief yawn yourself.

The eclipse will fantastic in Seattle (as opposed to outrageously eerie in central Oregon). It is also a rare event: The next total eclipse in Seattle will be April 23, 2563, at 5:44 p.m. Don’t wait for that event — enjoy this one.

Deep darkness lasts only a few moments. Mars (white-orange) will be visible about one fist above the sun. Venus will be easily visible 60 degrees above the southern horizon. You may also see some winter constellations if the skies aren’t hazy. Sirius the Dog Star and the belt stars of Orion will lie above the southern horizon.

Where to look:

The Sun will be where it always is at 10:22 a.m. — in the east southeast (to the upper left of Mt. Rainier from most parts of Seattle).

How to look:

Safe eclipse glasses are required to look directly at the sun. However, the dim view isn’t a very “wow” experience.�� There are other safe and far more memorable ways to see the event.

A leafy tree (particularly oak, cherry, plum) will work for forming a “constellation” of eclipse images on the ground or a wall (makes really cool photos!)  Find any tree through which speckles of sunshine reach the ground or a flat wall. They’re easy to find on campus. Watch the speckles turn into crescents as the event unfolds.�� (It’s a kick use the back of someone’s shirt as a viewing screen instead of a sidewalk.)

Alternately, you can use your fingers or a paper plate with small holes poked in it to form speckles.

Or look into a long box with a pinhole at the upper end and a sheet of white paper at the opposite end. Use a thick nail to form a clean pinhole. If you have the time, spray paint the box interior black and tape a sheet of clean white paper inside the box at the opposite end of the box from the pinhole.

Young kids will get a kick out of this pinhole camera. Two thick sheets of paper that form the equivalent of the ends of the box will work just fine, but the box is far easier to manipulate.

A few eclipse-related questions and answers:

• How fast does the eclipse shadow move? 2250 miles per hour.
• How wide is the path? About 70 miles.
• When was the previous solar eclipse in the U.S.? On . It passed over Portland, Yakima, Montana, central Canada, and Greenland.
• When and where is the next one in the U.S.? April 28 2024; its path runs from Texas to Maine.
• How frequent are total solar eclipses? There are 21 between July 1971 and July 2047, occurring about once every three and a half years, somewhere in the world.
• When is the last-ever total solar eclipse? In about half a billion years.
• Why is that? Because the moon is steadily receding from the Earth by 2.2 inches per year. Eventually it will no longer fully cover the disk of the sun.

A note on eclipse photography: Obsessing about camera settings during the height of an eclipse is the best way to distract yourself from this brief event.

Spend 90 percent of your time enjoying the eclipse and the strange, ephemeral world that you see around you.

Plan to take just one or two quick pictures, each with a horse, a fence, a lake, a tree, or a friend in the frame. (Use your flash.) This makes for very dramatic and memorable pictures. It helps to set your camera or mobile phone to HDR (if your camera has such a setting).

Put a person or the top of an iconic building in the eclipse picture for scale. (e.g., Red Square, the Quad, or the perimeter of the Hub lawn).

• Watch a NASA video:” “.”