Researchers observing with NASA’s James Webb Space Telescope have pinpointed silicate cloud features in a distant planet’s atmosphere. The atmosphere is constantly rising, mixing, and moving during its 22-hour day, bringing hotter material up and pushing colder material down.

The resulting brightness changes are so dramatic that it is the most variable planetary-mass object known to date. The team, led by Brittany Miles of the University of Arizona, also made extraordinarily clear detections of water, methane and carbon monoxide with Webb’s data, and found evidence of carbon dioxide. This is the largest number of molecules ever identified all at once on a planet outside our solar system.

Cataloged as VHS 1256 b, the planet is about 40 light-years away and orbits not one, but two stars over a 10,000-year period. “VHS 1256 b is about four times farther from its stars than Pluto is from our sun, which makes it a great target for Webb,” Miles said. “That means the planet’s light is not mixed with light from its stars.”

Higher up in its atmosphere, where the silicate clouds are churning, temperatures reach a scorching 1,500 degrees Fahrenheit (815 degrees Celsius).

Within those clouds, Webb detected both larger and smaller silicate dust grains, which are shown on a spectrum. “The finer silicate grains in its atmosphere may be more like tiny particles in smoke,” noted co-author Beth Biller of the University of Edinburgh in Scotland. “The larger grains might be more like very hot, very small sand particles.”

VHS 1256 b has low gravity compared to more massive brown dwarfs, which means that its silicate clouds can appear and remain higher in its atmosphere where Webb can detect them. Another reason its skies are so turbulent is the planet’s age. In astronomical terms, it’s quite young. Only 150 million years have passed since it formed—and it will continue to change and cool over billions of years.

In many ways, the team considers these findings to be the first “coins” pulled out of a spectrum that researchers view as a treasure chest of data. In many ways, they’ve only begun identifying its contents. “We’ve identified silicates, but better understanding which grain sizes and shapes match specific types of clouds is going to take a lot of additional work,” Miles said. “This is not the final word on this planet—it is the beginning of a large-scale modeling effort to fit Webb’s complex data.”

Although all of the features the team observed have been spotted on other planets elsewhere in the Milky Way by other telescopes, other research teams typically identified only one at a time. “No other telescope has identified so many features at once for a single target,” said co-author Andrew Skemer of the University of California, Santa Cruz. “We’re seeing a lot of molecules in a single spectrum from Webb that detail the planet’s dynamic cloud and weather systems.”

The team came to these conclusions by analyzing data known as spectra gathered by two instruments aboard Webb, the Near-Infrared Spectrograph (NIRSpec) and the Mid-Infrared Instrument (MIRI). Since the planet orbits at such a great distance from its stars, the researchers were able to observe it directly, rather than using the transit technique or a coronagraph to take this data.

There will be plenty more to learn about VHS 1256 b in the months and years to come as this team—and others—continue to sift through Webb’s high-resolution infrared data. “There’s a huge return on a very modest amount of telescope time,” Biller added. “With only a few hours of observations, we have what feels like unending potential for additional discoveries.”

What might become of this planet billions of years from now? Since it’s so far from its stars, it will become colder over time, and its skies may transition from cloudy to clear.

The researchers observed VHS 1256 b as part of Webb’s Early Release Science program, which is designed to help transform the astronomical community’s ability to characterize planets and the disks where they form.

The team’s paper, entitled “The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 Micron Spectrum of the Planetary-Mass Companion VHS 1256-1257 b,” will be published in The Astrophysical Journal Letters.

The work is currently published on the arXiv preprint server.

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Sky-gazers will be treated to a parade of planets near the end of month when Jupiter, Mercury, Venus, Uranus and Mars will appear together in the night sky.

On March 28, a large planetary alignment will take place when the five planets appear just after sunset, all within a 50-degree sector of the sky, according to sky tracking site Starwalk.

Jupiter and Mercury will appear near the horizon, in the constellation Pisces, while Venus will be visible higher in the sky on the constellation Aries, the sky-tracking site noted.

Next, Uranus will line up nearby but a pair of binoculars may be required to get a glimpse of the planet. Finally, Mars will appear higher in the sky, near the moon, to complete the five-planet alignment.

“Although March 28 is the best day for observation, the alignment will be visible several days before and after that date,” the website explained.

If the weather isn’t in your favour next week, there will be other opportunities to catch a planetary alignment this year, including another five-planet alignment on June 17. Mercury, Uranus, Jupiter, Neptune, and Saturn will be on parade that evening.

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Next year, 2024, is Solar Eclipse Year.

On April 8, 2024, a total solar eclipse will be visible from the south Pacific Ocean, northern Mexico, across the U.S. and through the Atlantic provinces of Canada.

More importantly, the total solar eclipse will be visible from southwestern Newfoundland, in the areas of Stephenville and across central Newfoundland through Terra Nova Park and Gander.

A partial eclipse will be visible across the province, with St. John’s and Corner Brook just outside the range of a total eclipse, an 80 per cent eclipse in Labrador City and a 70 per cent eclipse in Nain.

The 2024 solar eclipse will be the first eclipse crossing the province since 1970 and the only one until 2079.

For many, this is a once-in-a-lifetime event to see a total solar eclipse in Newfoundland and Labrador.

“Solar eclipses are special events in many cultures and have allowed scientists to make great discoveries.”

We are fortunate to even be able to observe a solar eclipse.

The Earth is the only place in our solar system where there is a moon that is about the same size in the sky (0.5 degree) as the sun.

Solar eclipses are special events in many cultures and have allowed scientists to make great discoveries.

When the moon passes in front of the sun, most of the light is blocked and we can see the sun’s corona (more about the corona below).

A note: make sure to wear appropriate eye protection during an eclipse to look at the sun.

The late Dr. Jay Pasachoff, an American astronomer, was so inspired by solar eclipses that he chased them around the world to experience more than 70 eclipses in about 50 years.

In a New York Times 2010 op-ed, he wrote: “There’s also the primal thrill this astronomical lightshow always brings the perfect alignment, in solemn darkness, of the celestial bodies that mean most to us.”

There is the thrill of observing solar eclipses and there is the thrilling science of them, too.

Thanks to solar eclipses, we learn about the sun’s corona, a thin layer of plasma that is just above the sun’s surface.

We normally can’t see it because it is so thin and has such a small density, but the temperature of the corona is about one million degrees Celsius.

It is believed that the corona is related to the sun’s magnetic field and to things like solar flares and mass ejections.

These flares and mass ejections impact the Earth through space weather and the aurorae — phenomena that those of us in the Northern Hemisphere recognize as the Northern Lights.

Scientific discovery

And it’s not just the sun.

Solar eclipses were important to provide some of the early evidence of Albert Einstein’s Theory of General Relativity.

Einstein predicted that light is bent by the gravity of stars.

So, if we can see stars behind the sun, they will appear to be in a slightly different location in the sky relative to each other than when we see them normally.

In 1919 scientists observed stars behind the sun that became visible during a solar eclipse and found that, indeed, their observations agreed with Einstein’s theory.

Town of Gander a major partner

Solar eclipses are fantastic events that connect humans to nature, celestial bodies and to the universe.

Next year’s celebration is an opportunity to celebrate science, nature and humanity.

Thanks to the enthusiasm and excitement of its staff and council, Prof. Svetlana Barkanova, Department of Physics, Grenfell Campus, and I are partnering with the Town of Gander to host a solar eclipse viewing party on April 8, 2024, and a science festival in the days before the eclipse.

The town is excited to be a major partner bringing people from across Newfoundland and Labrador to learn, discover and experience a total solar eclipse together.

The town has pledged to develop a budget to assist with the costs of this unique science festival, along with providing facilities, viewing sites and in-kind assistance.

The event is being planned in collaboration with a continuing science and community outreach program led by Prof. Barkanova and her team.

They deliver a large-scale scientific and cultural outreach program for youth in our province, especially rural youth, girls and Indigenous students, and is currently developing in-person and online seminars and workshops leading up to the solar eclipse.

“It is an ideal chance for us at Memorial to do what we do best — share what is great about our fields.”

This is a call to faculty, students and staff at Memorial University across all campuses to join in the celebration and help it grow and expand.

Not only will we have the opportunity to experience an amazing celestial event, it is a chance to come together in central Newfoundland and share the stories of what we do at Memorial from how we understand the sun and moon in astrophysics, in cultures, in literatures, in humanities and so on.

This is a call to action for your involvement; more participating colleagues means more public talks, Science on Tap events, outreach in schools and more.

It is an ideal chance for us at Memorial to do what we do best — share what is great about our fields and do so around this rare event in Newfoundland and Labrador.

Come join in for Solar Eclipse Year 2024 in Gander. Contact me via email.

Co-authored by Dr. Svetlana Barkanova, Department of Physics, Grenfell Campus, and Brian Williams, tourism development officer, Town of Gander.

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