New research supported by , a 天美影视传媒 postdoctoral researcher in astronomy, uncovered a contender for one of the earliest observed spiral galaxies containing a stellar bar 鈥� a notable visual feature that can play an important role in the evolution of a galaxy.

This finding helps constrain the timeframe in which bars could have first emerged in the universe. Analysis of light from the galaxy, called COSMOS-74706, places it on the cosmic timeline at about 11.5 billion years ago, or just two billion years after the birth of the universe.

at the 247th meeting of the American Astronomical Society on Jan. 8. A published study is forthcoming.

鈥淪tellar bars are typically seen in mature, well-evolved galaxies, so finding one just two billion years after the Big Bang is remarkable,鈥� said Cheng, who completed this work as a doctoral student at the University of Massachusetts Amherst. 鈥淭his discovery shows that massive disk galaxies were already dynamically organized at very early times, offering new insight into how galaxies assembled and evolved in the young universe.鈥�

While at Amherst, Cheng led the analysis of the galaxy鈥檚 physical properties and evolutionary history.

The 鈥渂ar鈥� in a barred galaxy isn鈥檛 an object itself, but a dense collection of stars and gas that is aligned in such a way that, in images taken perpendicular to a galactic plane, there appears to be a bright line bisecting the galaxy.

Despite appearing like a permanent feature, stellar bars are fluctuating density waves that form as the result of some kind of instability in the galaxy. They can be the result of 鈥渢idal perturbations,鈥� gravitational forces caused by something outside of the galaxy.听

鈥淚f you have a close interaction with a nearby galaxy, that can actually trigger the global instability that leads to the formation of a stellar bar,鈥� said lead author Daniel Ivanov, a graduate student in astronomy at the University of Pittsburgh.

Even without outside influences, a stable disc can slowly become unstable on its own. Over time, this process can naturally lead to the formation of stellar bars. They likely appear and disappear multiple times over the life of a galaxy.

Stellar bars can play a role shaping their galaxy鈥檚 evolution by funneling gas inward from the outer reaches of a galaxy, feeding the supermassive black hole in the center.听

The team members made their discovery as they were developing a catalog of barred and non-barred galaxies in a particular region of space. During this work, a couple of galaxies were flagged for their unusually high redshifts. This is an indication of how long the light had been traveling and, therefore, how long ago it was emitted.

Other researchers have reported earlier barred spiral galaxies, but the analysis of those are less conclusive because the methods used to measure the lights鈥� redshifts are not as definitive as spectroscopy, the method used to validate COSMOS-74706.听

Ivanov wasn鈥檛 necessarily surprised to find a barred spiral galaxy so early in the universe鈥檚 evolution 鈥� in fact, some simulations suggest bars forming as early as 12.5 billion years ago.听

But, he said: 鈥淚n principle, I think that this is not an epoch in which you expect to find many of these objects. It helps to constrain the timescales of bar formation. And it鈥檚 just really interesting.鈥澛�

This research was funded by NASA and The Brinson Foundation.

For more information, contact Cheng at yingjiec@uw.edu.

This story was adapted from a press release by .

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鈥檚 core to the tiny but bright star hidden within, the Webb observations paint a never-before-seen portrait of the nebula鈥檚 inner workings. The new imagery also helps scientists understand the origins of comic dust.

鈥淢ost of the material in rocks, gems, bones 鈥� really the Earth itself 鈥� arrived here as a cloud of tiny cosmic dust particles. Rocky planets are made of this stuff,鈥� said , a UW professor emeritus of astronomy and a member of the research team. 鈥淭he Butterfly Nebula is one of the nearest prolific sources of fresh cosmic dust, so it鈥檚 a great place to study how dust forms and disperses.鈥�

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 鈥渨ings鈥� of the butterfly. The torus-shaped cloud of dust and gas poses as the butterfly鈥檚 鈥渂ody鈥� 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鈥檚 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鈥檚 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鈥� origin.

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

鈥淏illions 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鈥檚 first surface,鈥� Balick said. 鈥淭he Butterfly enables us to look into the very start of this process.鈥�

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鈥檛 round at all 鈥� the Butterfly Nebula itself is a prime example of the unusual and mysterious shapes that they can take.

鈥淲hen I saw the new images, I realized there鈥檚 still a lot to learn about the formation and shaping of planetary nebulae 鈥� more than we ever anticipated,鈥� Balick said. 鈥淏ut that鈥檚 how science works. You peel the onion one layer at a time.鈥�

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

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鈥� 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.

New research from astronomers at the 天美影视传媒 uses the intriguing TRAPPIST-1 planetary system as a kind of laboratory to model not the planets themselves, but how the coming might detect and study their atmospheres, on the path toward looking for life beyond Earth.

The study, led by , a UW doctoral student in astronomy, finds that the James Webb telescope, set to launch in 2021, might be able to learn key information about the atmospheres of the TRAPPIST-1 worlds even in its first year of operation, unless 鈥� as an old song goes 鈥� clouds get in the way.

“The Webb telescope has been built, and we have an idea how it will operate,” said Lustig-Yaeger. “We used computer modeling to determine the most efficient way to use the telescope to answer the most basic question we’ll want to ask, which is: Are there even atmospheres on these planets, or not?”

His paper, “The Detectability and Characterization of the TRAPPIST-1 Exoplanet Atmospheres with JWST,” was in June in the Astronomical Journal.

The TRAPPIST-1 system, 39 light-years 鈥� or about 235 trillion miles 鈥� away in the constellation of Aquarius, interests astronomers because of its seven orbiting rocky, or Earth-like, planets. Three of these worlds are in the star’s habitable zone 鈥� that swath of space around a star that is just right to allow liquid water on the surface of a rocky planet, thus giving life a chance.

The star, TRAPPIST-1, was much hotter when it formed than it is now, which would have subjected all seven planets to ocean, ice and atmospheric loss in the past.

“There is a big question in the field right now whether these planets even have atmospheres, especially the innermost planets,” Lustig-Yaeger said. “Once we have confirmed that there are atmospheres, then what can we learn about each planet’s atmosphere 鈥� the molecules that make it up?”

Given the way he suggests the James Webb Space Telescope might search, it could learn a lot in fairly short time, this paper finds.

Astronomers detect exoplanets when they pass in front of or “transit” their host star, resulting in a measurable dimming of starlight. Planets closer to their star transit more frequently and so are somewhat easier to study. When a planet transits its star, a bit of the star’s light passes through the planet’s atmosphere, with which astronomers can learn about the molecular composition of the atmosphere.

Lustig-Yaeger said astronomers can see tiny differences in the planet’s size when they look in different colors, or wavelengths, of light.

“This happens because the gases in the planet’s atmosphere absorb light only at very specific colors. Since each gas has a unique ‘spectral fingerprint,’ we can identify them and begin to piece together the composition of the exoplanet’s atmosphere.”

Lustig-Yaeger said the team’s modeling indicates that the James Webb telescope, using a versatile onboard tool called the Near-Infrared Spectrograph, could detect the atmospheres of all seven TRAPPIST-1 planets in 10 or fewer transits 鈥� if they have cloud-free atmospheres. And of course we don’t know whether or not they have clouds.

If the TRAPPIST-1 planets have thick, globally enshrouding clouds like Venus does, detecting atmospheres might take up to 30 transits.

“But that is still an achievable goal,” he said. “It means that even in the case of realistic high-altitude clouds, the James Webb telescope will still be capable of detecting the presence of atmospheres 鈥� which before our paper was not known.”

Many rocky exoplanets have been discovered in recent years, but astronomers have not yet detected their atmospheres. The modeling in this study, Lustig-Yaeger said, “demonstrates that, for this TRAPPIST-1 system, detecting terrestrial exoplanet atmospheres is on the horizon with the James Webb Space Telescope 鈥� perhaps well within its primary five-year mission.”

The team found that the Webb telescope may be able to detect signs that the TRAPPIST-1 planets lost large amounts of water in the past, when the star was much hotter. This could leave instances where abiotically produced oxygen 鈥� not representative of life 鈥� fills an exoplanet atmosphere, which could give a sort of “false positive” for life. If this is the case with TRAPPIST-1 planets, the Webb telescope may be able to detect those as well.

Lustig-Yaeger’s co-authors, both with the UW, are astronomy professor , who is also principal investigator for the UW-based ; and astronomy doctoral student . The work follows, in part, on previous work by Lincowski modeling possible climates for the seven TRAPPIST-1 worlds.

“By doing this study, we have looked at: What are the best-case scenarios for the James Webb Space Telescope? What is it going to be capable of doing? Because there are definitely going to be more Earth-sized planets found before it launches in 2021.”

The research was funded by a grant from the NASA Astrobiology Program’s Virtual Planetary Laboratory team, as part of the Nexus for Exoplanet System Science (NExSS) research coordination network.

Lustig-Yaeger added: “It鈥檚 hard to conceive in theory of a planetary system better suited for James Webb than TRAPPIST-1.”

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For more information, contact Lustig-Yaeger at jlustigy@uw.edu.