The glowing nebula IC 2220, nicknamed the Toby Jug Nebula owing to its resemblance to an old English drinking vessel, is a rare astronomical find. This reflection nebula, located about 1200 light-years away in the direction of the constellation Carina (the keel), is a double-lobed, or bipolar, cloud of gas and dust created and illuminated by the red-giant star at its center. This end-of-life phase of red giant stars is relatively brief, and the celestial structures that form around them are rare, making the Toby Jug Nebula an excellent case study into stellar evolution.

This image, captured by the Gemini South telescope, one half of the International Gemini Observatory, operated by NSF’s NOIRLab, showcases the Toby Jug Nebula’s magnificent, nearly symmetrical double-looped structure and glowing stellar heart. These features are unique to red giants transitioning from aging stars to planetary nebulae [1] and therefore offer astronomers valuable insight into the evolution of low- to intermediate-mass stars nearing the end of their lives as well as the cosmic structures they form.

At the heart of the Toby Jug Nebula is its progenitor, the red-giant star HR3126. Red giants form when a star burns through its supply of hydrogen in its core. Without the outward force of fusion, the star begins to contract. This raises the core temperature and causes the star to then swell up to 400 times its original size. Though HR3126 is considerably younger than our Sun — a mere 50 million years old compared to the Sun’s 4.6 billion years — it is five times the mass. This allowed the star to burn through its hydrogen supply and become a red giant much faster than the Sun.

As HR 3126 swelled, its atmosphere expanded and it began to shed its outer layers. The expelled stellar material flowed out into the surrounding area, forming a magnificent structure of gas and dust that reflects the light from the central star. Detailed studies of the Toby Jug Nebula in infrared light have revealed that silicon dioxide (silica) is the most likely compound reflecting HR3126’s light.

Astronomers theorize that bipolar structures similar to those seen in the Toby Jug Nebula are the result of interactions between the central red giant and a binary companion star. Previous observations, however, found no such companion to HR3126. Instead, astronomers observed an extremely compact disk of material around the central star. This finding suggests that a former binary companion was possibly shredded into the disk, which may have triggered the formation of the surrounding nebula.

In about five billion years from now, when our Sun has burned through its supply of hydrogen, it too will become a red giant and eventually evolve into a planetary nebula. In the very distant future, all that will be left of our Solar System will be a nebula as vibrant as the Toby Jug Nebula with the slowly cooling Sun at its heart.

The image was processed by NOIRLab’s Communication, Education & Engagement team as part of the NOIRLab Legacy Imaging Program. The observations were made with Gemini South on Cerro Pachón in Chile using one of the dual Gemini Multi-Object Spectrographs (GMOS). Though spectrographs are designed to split light into various wavelengths for study, the GMOS spectrographs also have powerful imaging capabilities, as demonstrated by this exceptional view of the Toby Jug Nebula.

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[1] The term “planetary nebulae” is a misnomer; they are unrelated to planets. The term was likely first used in the 1780s by astronomer William Herschel, who noted their seemingly round, planet-like shape when observed through early telescopes.

The alignment of planetary nebulae was discovered ten years ago by a Manchester PhD student, Bryan Rees, but has remained unexplained.

New data obtained with the European Southern Observatory Very Large Telescope in Chile and the Hubble Space Telescope, published in Astrophysical Journal Letters, has confirmed the alignment but also found a particular group of stars that is responsible, namely close binary stars.

Planetary nebulae are clouds of gas that are expelled by stars at the end of their lives — the Sun will also form one about five billion years from now. The ejected clouds are ‘ghosts’ of their dying stars and they form beautiful structures such as an hourglass or butterfly shape.

The team studied a group of so-called planetary nebulae found in the Galactic Bulge near the centre of our Milky Way. Each of these nebulae are unrelated and come from different stars, which were born at different times, and spend their lives in completely different places. However, the study found that many of their shapes line up in the sky in the same way and are aligned almost parallel to the Galactic plane (our Milky Way).

This is in the same direction as found by Bryan Rees a decade ago.

The new research, led by Shuyu Tan, a student at the University of Hong Kong, found that the alignment is present only in planetary nebulae which have a close stellar companion. The companion star orbits the main star at the centre of the planetary nebulae in an orbit closer than Mercury is to our own Sun.

The planetary nebulae that do not show close companions do not show the alignment, which suggests that the alignment is potentially linked to the initial separation of the binary components at the time of the star’s birth.

Albert Zijlstra, co-author and Professor in Astrophysics at The University of Manchester, said: “This finding pushes us closer to understanding the cause for this mysterious alignment.

“Planetary nebulae offer us a window into the heart of our galaxy and this insight deepens our understanding of the dynamics and evolution of the Milky Way’s bulge region.

“The formation of stars in the bulge of our galaxy is a complex process that involves various factors such as gravity, turbulence, and magnetic fields. Until now, we have had a lack of evidence for which of these mechanisms could be causing this process to happen and generating this alignment.

“The significance in this research lies in the fact that we now know that the alignment is observed in this very specific subset of planetary nebulae.”

The researchers investigated 136 confirmed planetary nebulae in the galaxy bulge — the thickest section of our Milky Way composed of stars, gas and dust — using the European Southern Observatory Very Large Telescope, which has a main mirror diameter of eight metres.

They also re-examined and re-measured 40 of these from the original study using images from the high-resolution Hubble Space Telescope.

Prof Quentin Parker, the corresponding author from the University of Hong Kong, suggests the nebulae may be shaped by the rapid orbital motion of the companion star, which may even end up orbiting inside the main star.

The alignment of the nebulae may mean that the close binary system preferentially forms with their orbits in the same plane.

Although further studies are needed to fully understand the mechanisms behind the alignment, the findings provide important evidence for the presence of a constant and controlled process that has influenced star formation over billions of years and vast distances.

A study published today in Global Change Biology, led by researchers at UC Santa Barbara, found that while California’s network of marine protected areas (MPAs) provide many social and ecological benefits, they are not resilient to the effects of ocean warming. MPAs are locations in the ocean where human activities such as fishing are restricted to conserve and protect marine ecosystems, habitats, species and cultural resources. The study, part of a 10-year review of California’s MPA network conducted at UCSB’s National Center for Ecological Analysis & Synthesis (NCEAS), found that marine heatwaves impact ecological communities regardless of whether they are protected inside MPAs.

“MPAs in California and around the world have many benefits, such as increased fish abundance, biomass and diversity,” said Joshua Smith, who led the study while he was a postdoctoral researcher at NCEAS . “But they were never designed to buffer the impacts of climate change or marine heatwaves.”

Smith and co-authors from all over the world were part of an NCEAS working group formed to synthesize decades of long-term ecological monitoring data from California’s diverse ocean habitats. The group, co-led by Jenn Caselle, a researcher with UCSB’s Marine Science Institute, and Kerry Nickols, a professor from Cal State University Northridge who now works with the non-profit Ocean Visions, aimed to provide actionable scientific results to California’s policy makers and natural resource managers, as part of a statewide Decadal Evaluation of the MPA network. Their analyses spanned the largest marine heatwave on record, which rolled through the Pacific Ocean toward California from 2014-2016. The monster marine heatwave was formed from an environmental double-whammy — unusual ocean warming nicknamed “The Blob,” followed by a major El Niño event that prolonged the sweltering sea temperatures. The marine heatwave blanketed the West Coast from Alaska to Baja and left a wake of altered food webs, collapsed fisheries, and shifted populations of marine life among various other consequences.

As MPA managers around the world face increasing climate shocks, the extent to which MPAs can buffer the worst of these events has become an important question. The working group scientists asked how the ecological communities in California’s protected areas fared after such a severe and prolonged heatwave: Would the communities shift and if so, how? Would they ‘bounce back’ when the marine heatwave subsided? Could the marine protected areas protect sensitive populations or facilitate recovery?

To find answers to their questions, they synthesized over a decade of data collected from 13 no-take MPAs located in a variety of ecosystems along the Central Coast: rocky intertidal zones, kelp forests, shallow and deep rocky reefs. The team looked at fish, invertebrates and seaweed populations inside and outside these areas, using data from before, during and after the heatwave.

They also focused on two of these habitats, rocky intertidal and kelp forests, at 28 MPAs across the full statewide network to gauge whether these locations promoted one particular form of climate resilience — maintaining both population and community structure.

“We used no-take MPAs as a type of comparison to see whether the protected ecological communities fared better to the marine heatwave than places where fishing occurred,” said Smith, now an Ocean Conservation Research Fellow at Monterey Bay Aquarium.

The results are somewhat sobering, though not altogether unexpected.

“The MPAs did not facilitate resistance or recovery across habitats or across communities,” Caselle said. “In the face of this unprecedented marine heatwave, communities did change dramatically in most habitats. But, with one exception, the changes occurred similarly both inside and outside the MPAs. The novelty of this study was that we saw similar results across many different habitats and taxonomic groups, from deepwater to shallow reefs and from fishes to algae.”

The implication of these findings, according to Smith, is that every part of the ocean is under threat from climate change. “MPAs are effective in many of the ways they were designed, but our findings suggest that MPAs alone are not sufficient to buffer the effects of climate change.”

The key question now is what will happen in the future? At the time of this study using data through 2020, the ecological communities have not returned to their former, pre-heatwave state. According to the paper, these ecological communities shifted toward a “pronounced decline in the relative proportion of cold-water species and an increase in warm water species.” For example, increases in the abundance of the señorita fish (Oxyjulis californica), a subtropical species with warm water affinity and previously rare in central California, had an outsized influence on the shift of communities. Whether these species persist in their new locations remains to be seen.

“This study makes it clear why long-term monitoring of California’s MPAs is so critical,” said Caselle. “Some of these time series are longer than 25 years at this point and the data are critical to understanding and readying human communities for the changes occurring in our marine communities.” Continued study will show if future shifts in marine communities occur at different rates or to different base states in MPAs compared to fished areas.

Despite the limited ability of MPAs to resist the grip of the marine heatwave, they do confer benefits, not the least of which is the ability to study the complex effects of climate change in areas not impacted by fishing. As areas of minimal human interference that are regularly monitored, they present opportunities to study the response of marine ecosystems to shifting conditions and potentially tailor management techniques accordingly. Moreover, as Smith stated, “the ecological communities in MPAs are still being protected, even if they are different as a result of the heatwave. Given that marine heatwaves are anticipated to increase in frequency and magnitude into the future, swift climate action and nature-based solutions are needed as additional pathways to enhance the health of our oceans.”

Kerry Nickols adds, “With the devastating impacts of climate change already apparent, it is very important that we are upfront about climate solutions — as long as we are burning fossil fuels and warming the globe marine ecosystems will be at risk, even if they are protected from fishing.”

This paper is the first in a series led by the NCEAS working group. Forthcoming articles examine human engagement across the California MPA network, the effect of MPAs on fish populations and fisheries, and a synthesis of marine protected areas that work for people and nature.