NASA’s PACE Mission Studies Smoke, Fires

With the North American fire season underway, and a record number of acres already burned nationwide, NASA’s Plankton, Aerosol, Cloud, and ocean Ecosystem (PACE) satellite’s three instruments are observing vegetation precursors to fires, along with plumes of smoke and their movement. This data will help scientists piece together clues that deepen their understanding of wildfires.

“The challenge that we have is to take those clues and use them in a meaningful way, so our models of Earth properly represent what’s happening,” said Kirk Knobelspiesse, a remote sensing scientist working on the PACE mission at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

While the satellite, which launched in February 2024, was designed to study Earth’s ocean and atmosphere, it has an unexpected capability: monitoring changes to vegetation. It can also tell us about burn scars, the charred area of land left behind after a wildfire. 

“The PACE satellite observes land too, and does it really well,” said Skye Caplan, terrestrial lead for the PACE mission at NASA Goddard. “There is so much to explore with a new hyperspectral data set.”

The Ocean Color Instrument on board PACE is a hyperspectral instrument, observing the planet in several hundred different wavelengths of visible, near infrared, and ultraviolet light. This breadth of the spectrum allows it to gather data on the health of plants, such as their state of stress, dryness, and their relative pigment balance, all of which assist in identifying high fire-risk areas. Land managers can use this data to distribute resources to help mitigate fire risk.

This instrument views the entire Earth daily, with more frequent coverage at high latitudes. With this frequency, on clear days, PACE scientists can quickly assess the aftermath of fires, determining the location and span of a burn scar. Areas that have been burned by wildfire often see increased flood and landslide risk. It’s important to identify these high-risk areas and monitor how they evolve through time, Caplan said.

Using wavelengths in the ultraviolet range, the Ocean Color Instrument can also monitor the smoke after a fire, along with information on how high in the atmosphere these particles drift — height plays a role in how far the particles travel and the systems they impact. The instrument, with its ultraviolet data, expands on fire observations from other satellite instruments, such as the Visible Infrared Imaging Radiometer Suite and the Moderate Resolution Imaging Spectroradiometer.

The other two instruments on PACE, the Hyper-Angle Rainbow Polarimeter 2 and the Spectro-polarimeter for Planetary Exploration one, are rich with information about the composition of aerosols from vastly different regions, said Andrew Sayer, PACE project science lead for atmospheres from the Ocean Color Instrument at NASA Goddard.

By measuring characteristics of light as it reflects off particles in the atmosphere, these two instruments can determine the quantity of these particles, along with their chemical properties, color, size, and shape. Scientists use this information to differentiate smoke from other particulates. Smoke particulates are typically light absorbing — appearing gray, black, or brown in color — and are small in size compared to other aerosols PACE views, such as pollutants and dust.

Data from PACE will help scientists create more accurate wildfire models and simulate future events, said Knobelspiesse, the satellite’s polarimeter lead. “We’ll be able to then look at different scenarios of emissions in the future and see how smoke that’s created in one location can impact other parts of the Earth system.”

By Erica McNamee

NASA’s Goddard Space Flight Center, Greenbelt, Md.

Explore More

4 min read

NASA’s PACE Mission Reveals a Year of Terrestrial Data on Plant Health

A lot can change in a year for Earth’s forests and vegetation, as springtime and…

Article


1 year ago

5 min read

New NASA Satellite To Unravel Mysteries About Clouds, Aerosols

Some of the same properties of light and optics that make the sky blue and…

Article


3 years ago

5 min read

NASA-Funded Study Shows Wildfire Smoke’s Hidden Ozone Toll

Over the last decade, wildfires have worsened ground-level ozone pollution across much of the contiguous…

Article


3 weeks ago

Powered by WPeMatico

Get The Details…

Hubble Spies Starry Chandelier

The subject of today’s NASA/ESA Hubble Space Telescope image is an ancient inhabitant of our galaxy. This sparkling scene features a globular cluster: a collection of tens of thousands to millions of stars, all tightly bound together under the influence of gravity. There are more than 150 globular clusters in our galaxy, though there may be others still undiscovered, hidden from view by dust or densely packed fields of stars.

This globular cluster, NGC 6723, sometimes called the Chandelier Cluster, is much like its namesake because it sparkles with countless lights. However, each ‘lightbulb’ in this chandelier is an individual star 27,000 light-years away in the constellation Sagittarius (the Archer).

Globular clusters like NGC 6723 contain some of the oldest stars in our galaxy. These clusters have ages that often exceed 10 billion years old, and some are nearly as old as the universe itself. Astronomers think globular clusters are some of the first structures that formed in our galaxy, coalescing potentially billions of years before the thin disk of stars in which our Sun orbits. The details of how globular clusters formed, however, are not yet certain.

Astronomers initially thought that all stars in a globular cluster formed at the same time in a single flourish of star formation. This would mean that all stars in a globular cluster would be the same age and made of the same mixture of chemical elements. Now, thanks to observations from telescopes like Hubble, researchers know that these seemingly simple stellar populations have more complex histories than originally thought.

Hubble first observed NGC 6723 as part of an ambitious survey dedicated to demystifying the properties of globular clusters in our Milky Way galaxy. In this observing program (#10775, PI: Sarajedini), researchers used Hubble to study 65 globular clusters in our galaxy in visible and near-infrared light. That data allowed researchers to study everything from the ages of globular clusters to the process through which massive stars sink to the center of a star cluster and lower-mass stars drift toward the cluster outskirts. This survey has been immensely scientifically valuable, and these observations have inspired several hundred published research papers.

In a later observing program (#13297, PI: Piotto), researchers set their sights again on many of these same clusters, including NGC 6723. This time, they used Hubble’s unique sensitivity to ultraviolet light to detect the subtle variations in chemical composition between the stars of globular clusters and determine the age spread among the clusters’ stars. For NGC 6723, researchers found evidence of two closely-spaced periods of star formation, the second occurring within 634 million years of the first. (‘Closely-spaced’ is relative; 634 million years is a blink of an eye for a star cluster that is more than 10 billion years old!)

Thanks to these findings, astronomers are on the path to understanding how and when globular clusters formed — and Hubble observations of celestial chandeliers like NGC 6723 are lighting the way.

Text Credit: ESA/Hubble

Media Contact:

Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, MD
claire.andreoli@nasa.gov

Keep Exploring

Discover More Topics From Hubble

Hubble Space Telescope

Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.

Hubble’s Star Clusters

Hubble e-Books

Hubble’s Cosmic Adventure

Powered by WPeMatico

Get The Details…

The Battle for Sullivan’s Island

As Thomas Jefferson and the Committee of Five presented their first draft of the Declaration of Independence in Philadelphia on June 28, 1776, several British warships and thousands of troops were massing around Sullivan’s Island in South Carolina.

The pitched battle for the sandy barrier island at the mouth of Charleston Harbor that played out over the course of that June day was one of the most significant in the early stages of the Revolutionary War. By nightfall, largely untested colonial troops had decisively defeated the British, an outcome that helped save Charleston from occupation and buoyed American spirits at a critical stage of the war.

The Landsat 8 satellite captured this image of the island on June 3, 2026. Two hundred fifty years earlier, the sandy beaches, salt marshes, and general shape of the island would have looked similar, though with less evidence of roads or other signs of human development.

There certainly would have been some signs of human activity on the island, however. Quite noticeable would have been Fort Sullivan, a large square structure built from palmetto logs on the southern tip of the island, near the entrance to the harbor. Though one side of the fort, assembled largely by enslaved people, was still unfinished at the time of the battle, the other sides had 16-foot-wide walls packed with sand and containing planked gun platforms that mounted 31 cannons.

Historical maps show at least one road extending from the southern to northern tip of Sullivan’s Island, where hundreds of colonial soldiers were also encamped to protect Breach Inlet from a force of roughly 3,000 British troops massing on nearby Long Island (now Isle of Palms). When the battle began, historians estimate that there were roughly 800 colonial troops, including dozens of Catawba warriors, defending the northeastern part of Sullivan’s Island, embedded within earthen defenses and manning two artillery pieces.

When the British attack came on the morning of June 28, 1776, both military tactics and geography played critical roles in determining the outcome. Having been told the water at the inlet was less than 18 inches (46 centimeters) deep at low tide, the British commander had planned to have his forces walk across Breach Inlet on foot. But he was forced to pivot to a more dangerous amphibious assault using flatboats when he realized the shallowest part of the break was at least 7 feet (2 meters) deep at low tide. Traveling by flatboat limited the number of British troops who could cross the channel at once, making it easier for colonial defenders to repel them during fierce skirmishing throughout the day.

On the other side of the island, British warships had dropped anchor near Fort Sullivan and begun launching thousands of cannonballs and exploding shells at the fort. However, the natural durability and pliability of the palmetto wood absorbed incoming fire “like sponges,” Colonel William Moultrie, the fort’s commanding officer, later noted in his memoirs.

Most incoming shells that fell within the fort’s walls were neutralized. There was a marshy “morass” in the center of the fort, Moultrie wrote, that “swallowed” up incoming fire “instantly.” Shells that made it over the walls and “fell in the sand, in and about the fort, were immediately buried, so that few of them burst amongst us,” he wrote.

With their limited powder, the colonists focused their fire on the ship carrying the British commander, Sir Peter Parker, severely damaging it and ultimately killing 40 people on board. By the evening, exhausted from the 10-hour battle and making little progress, the British forces retreated.

“We never had such a drubbing in our lives,” one Royal Navy sailor wrote. After the battle, the fort became known as Fort Moultrie, and the palmetto tree began appearing on the state seal in what would prove to be an enduring symbol of colonial pride and resistance. Six days after the battle, the Declaration of Independence was adopted in Philadelphia.

NASA Earth Observatory images by Michala Garrison, using Landsat data from the U.S. Geological Survey. Story by Adam Voiland.

Downloads

June 3, 2026: Detailed view

JPEG (1.35 MB)

June 3, 2026: Wide view

JPEG (24.60 MB)

References & Resources

• American Battlefield Trust, Sullivan’s Island. Accessed June 25, 2026.
• George Washington Presidential Library at Mount Vernon, Battle of Sullivan’s Island. Accessed June 25, 2026.
• The Island Packet (2024, April 20) Know why SC is nicknamed The Palmetto State? There’s more history to it than you may think. Accessed June 25, 2026.
• Journal of the American Revolution (2023, May 11) Danger at the Breach. Accessed June 25, 2026.
• Moultrie, W. (1802) Memoirs of the American Revolution. Accessed June 25, 2026.
• NASA Earth Observatory (2018, June 10) History and Seaports in Charleston. Accessed June 25, 2026.
• National Museum of the United States Army, The Royal Navy Assault on Sullivan’s Island. Accessed June 25, 2026.
• National Park Service Fort Moultrie. Accessed June 25, 2026.
• National Park Service (1968, June 30) The Battle of Sullivan’s Island. Accessed June 25, 2026.
• Princeton University Drafting the Declaration of Independence. Accessed June 25, 2026.
• Royal Collection Trust (1776) Map of Fort Sullivan and Charlestown, 1776 (Fort Moultrie, Sullivan’s Island, South Carolina, USA). Accessed June 25, 2026.

You may also be interested in:

Stay up-to-date with the latest content from NASA as we explore the universe and discover more about our home planet.

America’s Emerald Isle

3 min read

Beaver Island is one in a string of verdant and scenic jewels in a northern Lake Michigan archipelago.

Article

A Sea of Spinning Clouds

3 min read

Icy, isolated Peter I Island stirred up a show in the atmosphere off the West Antarctic coast.

Article

Fire Chars Santa Rosa Island

2 min read

The blaze spread across the southern side of the second-largest island in California’s Channel Islands National Park.

Article

Keep Exploring

Discover More from NASA Earth Science

Subscribe to Earth Observatory Newsletters

Subscribe to the Earth Observatory and get the Earth in your inbox.

Earth Observatory Image of the Day

NASA’s Earth Observatory brings you the Earth, every day, with in-depth stories and stunning imagery.

Explore Earth Science

Earth Science Data

Open access to NASA’s archive of Earth science data

Powered by WPeMatico

Get The Details…

Expedition 73 Crew Reflects on Science, Teamwork, and Life in Orbit 

On June 16, astronauts and cosmonauts gathered at Space Center Houston to share stories from their missions aboard the International Space Station and recognize the teamwork and people on the ground that made their missions possible. 

The Expedition 73 Welcome Home Ceremony brought together members of NASA’s SpaceX Crew-10, Soyuz MS-27, and NASA’s SpaceX Crew-11 missions. During the event, the crews reflected on the science, partnerships, and international collaboration that defined their time in orbit. 

Remarks were delivered by NASA’s Johnson Space Center Director Vanessa Wyche, Low Earth Orbit Program’s Deputy Manager for the International Space Station Dina Contella, Richard Jones with NASA’s commercial crew office, Flight Operations Director Norm Knight, Johnson Employee Relations Lead David Kelley, and Space Center Houston Chief Operating and Strategy Officer Keesha Bullock. Together, they recognized the accomplishments of the crews and the team members who helped make the expedition a success. 

Wyche welcomed the crews home and reflected on the accomplishments of Expedition 73. 

“Together, these crews exemplified professionalism, resilience, and the spirit of international cooperation,” Wyche said. “Their work ensured the continued success of the International Space Station Program and demonstrated the strength of our multi-vehicle crew transportation strategy.” 

During the expedition, all available docking ports were occupied simultaneously for the first time, with eight spacecraft attached to the station. The crew also supported visiting missions, including Axiom Mission 4, and multiple cargo deliveries while maintaining a full schedule of scientific investigations. 

Crew members completed three spacewalks, installing hardware that supports future solar array upgrades and maintenance activities critical to station operations.  

The ceremony also recognized the workforce whose dedication supported every aspect of Expedition 73, from mission planning and operations to research, training, and crew safety. 

“You learned each other’s languages, and often, when we didn’t know the right answers, you partnered with us, and you would come up with the answers and help,” said International Space Station Program Deputy Manager Dina Contella. “You really helped make us successful.” 

She noted that collaboration extended well beyond the crew in orbit, with teams across the program matching that dedication throughout the expedition.  

Contella shared that Expedition 73 included six cargo missions, the inaugural flight of JAXA’s (Japan Aerospace Exploration Agency) HTV-X1 cargo spacecraft, and more than 37,000 pounds of supplies, equipment, and scientific investigations delivered to the space station.  

She also thanked the Commercial Crew Program and Flight Operations teams for helping safely transport crews to and from the station and support mission operations. 

More than 1,000 employees representing 40 teams received NASA Group Achievement Awards, while 23 individuals were honored with Superior Achievement Awards for their contributions to the mission. 

NASA astronaut Zena Cardman and JAXA astronaut Kimiya Yui received NASA Exceptional Bravery Honors for demonstrating exceptional courage, leadership, and composure during a medical event. NASA astronaut Chris Williams also received the honor but was unable to attend because he remains aboard the space station. 

Flight Operations Director Norm Knight thanked the teams that supported Expedition 73 from the ground while recognizing the crews’ contributions throughout their missions. “You represent an astronaut corps that is the best of the best, epitomizing courage and teamwork,” Knight told the crew. “Every opportunity or challenge that came your way, you met with confidence and creativity.” 

Crew members reflected on the station’s legacy as a platform for discovery, innovation, and international partnership after more than 25 years of continuous human presence in orbit. 

Research conducted during Expedition 73 included investigations in human physiology, biology, materials science, pharmaceutical development, and technologies designed to benefit life on Earth and future exploration missions. 

The crews also discussed research aboard the station that will help prepare NASA for future missions to the Moon and Mars, including advanced life-support systems and water recovery technologies. 

Beyond science and operations, the crew built strong bonds during their months in orbit. They marked birthdays, holidays, and mission milestones together, often creating elaborate cakes from the limited ingredients available aboard the station. 

Many crew members said their strongest memories centered on the people around them, and that trust and teamwork remained essential to mission success. 

Viewing Earth from orbit provided the crew with a powerful reminder of humanity’s shared connection. 

“When you look back at Earth, what we have in common is so much more important than what makes us different,” said McClain. “We’re all on this one planet. We’re all on the same crew.” 

The evening concluded with the crew expressing gratitude to all those who supported their missions from launch through landing. 

“It was overwhelming in the most wonderful way to step off that aircraft and see so many team members who had supported us and see family and friends for the first time,” said Cardman. “We are so grateful.” 

View the list of award recipients here. 

Watch the full Expedition 73 crew debrief and awards ceremony below.  

Explore More

3 min read

A Turquoise Tint for the Black Sea

Phytoplankton added a milky blue hue to the waters of the Black Sea and nearby…

Article


20 hours ago

5 min read

NASA at the Ion: Orion Lessons from Artemis II Shape NASA’s Moon to Mars Path

Article


1 day ago

2 min read

Astronaut Jessica Meir Assists With Hardware Updates for NASA’s Cold Atom Lab

Description NASA astronaut Jessica Meir inspects optical fibers while installing hardware updates to the agency’s…

Article


1 week ago

Powered by WPeMatico

Get The Details…
Sumer Loggins