Landsat Launch Brings City of Lompoc Together

Landsat team members from NASA, partner agencies and companies, and the city of Lompoc cut the ceremonial ribbon to dedicate the Landsat mural in downtown Lompoc, California on September 26. Credit: NASA / Jessica Evans

By Jessica Merzdorf Evans //LOMPOC, CALIFORNIA//

In early 2021, local artist (and Lompoc Mural Society curator) Ann Thompson competed in and won the call for artists to commemorate Landsat 9’s launch and the Landsat program’s 50th anniversary. Along with representatives from NASA, the U.S. Geological Survey, United Launch Alliance, and the city of Lompoc, Thompson helped dedicate the mural for its official opening on September 26, 2021, one day before Landsat 9’s launch.

Artist Ann Thompson poses with her newly-dedicated “50th Anniversary of Landsat” mural in downtown Lompoc, California. Credit: NASA / Jessica Evans

Lompoc, California, has a lot of murals — 40 and counting, according to the city’s website. Some depict local flora and fauna, some show important events and people in the city’s history. The new mural depicts a stylized Landsat 9 orbiting Earth, with colorful pull-out frames showing Landsat images of changing glaciers, bright landscapes, and Santa Barbara County, California – home of Lompoc and Vandenberg Space Force Base. Another pull-out in the corner shows the timeline of the Landsat program, from Landsat 1’s launch in 1972 through Landsat 9.

This image shows the timeline of Landsat launches, from Landsat 1 in 1972 through Landsat 9 in 2021. Credit: NASA / Matthew Radcliff

The city of Lompoc sponsored or highlighted a number of events in the week leading up to launch, including workshops, educational events, talks, and art exhibits. 

At the Lompoc Aquatic Center across town, educators from the Landsat and ICESat-2 teams (Ice, Cloud and Land Elevation Satellite-2) demonstrated how their two missions track land and sea ice around the world. 

Landsat education outreach coordinator Allison Nussbaum shares Landsat materials and information with a family at the Lompoc Aquatic Center on September 26. Credit: NASA / Jessica Evans
ICESat-2 outreach lead Valerie Casasanto places an inflatable penguin into the pool at the Lompoc Aquatic Center on September 26th. Casasanto and her Landsat colleagues ran demonstrations on land and sea ice at the aquatic center as part of the outreach events surrounding Landsat 9’s launch. Credit: NASA / Jessica Evans

Launching a new satellite to space is often more than just a scientific achievement – it can be a community-wide event that gives educators, artists, and local citizens a chance to be part of the celebration. This week, the city of Lompoc is helping to paint a picture of the Landsat program’s future.

Liftoff for Landsat 9

The United Launch Alliance (ULA) Atlas V rocket with the Landsat 9 satellite onboard launches, Monday, Sept. 27, 2021, from Space Launch Complex 3 at Vandenberg Space Force Base in California. The Landsat 9 satellite is a joint NASA/U.S. Geological Survey mission that will continue the legacy of monitoring Earth’s land and coastal regions. Photo Credit: (NASA/Bill Ingalls)
The United Launch Alliance (ULA) Atlas V rocket with the Landsat 9 satellite onboard launches, Monday, Sept. 27, 2021, from Space Launch Complex 3 at Vandenberg Space Force Base in California. The Landsat 9 satellite is a joint NASA/U.S. Geological Survey mission that will continue the legacy of monitoring Earth’s land and coastal regions. Photo Credit: NASA/Bill Ingalls

By Jessica Merzdorf Evans //LOMPOC, CALIFORNIA//

11AM, Lompoc Airport

Launch day dawned gray and cool, with low-hanging cloud cover and a light drizzle. While the launch crew ran through their final procedures and checks before launch, I went to the public viewing site at Lompoc Airport, where several tents’ worth of activities and a “not-quite-life-sized” cutout of Landsat 9 greeted visitors.

In the activity tents, families were solving floor and table puzzles with Landsat imagery, while members of the outreach team helped kids make colorful mosaic art, use “pixel” stickers to reconstruct an image, and understand how satellites measure sea ice.

Young guests use colored “pixel” stickers to reconstruct a Landsat image in the activity tent at Lompoc Airport on September 27th. Credit: NASA / Jessica Evans
Young guests use colored “pixel” stickers to reconstruct a Landsat image in the activity tent at Lompoc Airport on September 27th. Credit: NASA / Jessica Evans

Ten minutes before launch, the tents started to empty out as people moved toward the open airport runway that pointed toward the launch site, about 10 miles away. I moved into the VIP viewing area reserved for NASA personnel and invitees. Some settled in for a view from bleachers or sheltered under a tent; some trekked far down the empty runway. I decided to head down the runway and try to get a glimpse of the Atlas V rocket as it cleared the launch pad.

Because of the low-hanging clouds, our view of the launch was three seconds of bright flaming light on the horizon before the rocket was swallowed up in the gray sky. Even from ten miles away, however, I could see the exhaust clouds billowing up from the launch pad and hear the earth-shaking, deep bass roar of the powerful engines powering the rocket toward orbit.

The gathered crowd strained their eyes eagerly toward the sky, hoping to catch a glimpse of the rocket as it hurtled toward space. Some people embraced as they felt the sound wash over them; some pointed or shaded their eyes; some cheered and clapped, while others stood quietly to listen to the rocket’s roar arcing high into the sky and overhead.

The Atlas V rocket carrying Landsat 9 and four CubeSats lifts off from the launchpad at 11:12AM Pacific time / 2:12PM Eastern time, Monday, September 27th, as employees and guests of NASA and partner agencies look on. Credit: NASA / Jessica Evans
The Atlas V rocket carrying Landsat 9 and four CubeSats lifts off from the launchpad at 11:12AM Pacific time / 2:12PM Eastern time, Monday, September 27th, as employees and guests of NASA and partner agencies look on. Credit: NASA / Jessica Evans

The payload and booster reached orbit about 16 minutes after launch, and Landsat 9 separated from its booster about an hour later, joining Landsat 8 and the rest of NASA’s Earth-observing fleet.

One special guest at the airport was Virginia Norwood, affectionately known as the “Mother of Landsat.” Norwood and her team designed and built the Multispectral Scanner System aboard Landsat 1, half a century ago.

Virginia T. Norwood (center, with cane), the “Mother of Landsat,” poses with the “Ladies of Landsat” group at a post-launch talk and celebration at Montemar Wines, Lompoc, California, on September 27th. Credit: NASA / Jessica Evans
Virginia T. Norwood (center, with cane), the “Mother of Landsat,” poses with the “Ladies of Landsat” group at a post-launch talk and celebration at Montemar Wines, Lompoc, California, on September 27th. Credit: NASA / Jessica Evans

Landsat 9 is safely in orbit and ready to start collecting data and taking its place in the nearly 50-year legacy of Landsat Earth observations. But that legacy is not only Landsat’s critical data continuity and technical achievements – it is also the legacy of the engineers, scientists, technicians, and resource managers who keep the program thriving, decade after decade.

In Lompoc, Scientists Gather for Landsat Trivia Night

By Jessica Merzdorf Evans //LOMPOC, CALIFORNIA//

It’s a smoky Saturday evening in the small town of Lompoc, California, and most of the streets are quiet — except for the warmly lit tables and flickering tiki torches in the outdoor dining area at Hangar 7. It’s Landsat Trivia Night, and the small restaurant is bustling with about three dozen scientists, engineers, project managers, and techies of all sorts from NASA, the U.S. Geological Survey, and the United Launch Alliance. They’ve gathered under the lights to enjoy pizza and drinks and to show off their knowledge of the 49-year-old Landsat program and its nine satellites.

I take my position along a stucco wall with a huge mural of local plants and animals and listen as the teams rev up for their first question.

“What was the name of Landsat 1 at the time of its launch?” The voice comes from Ginger Butcher, Landsat’s outreach coordinator. Guests lean in to discuss.

Not being a participant, I quietly check Google for the correct answer. It’s ERTS, the Earth Resources Technology Satellite. Launched in 1972, Landsat 1 / ERTS was the first satellite launched to space with the goal of studying and monitoring Earth’s land masses, and it pioneered the science and technology that undergirds much of our Earth-observing research today.

The teams hand Ginger their guesses on pieces of paper. Unsurprisingly, most get the question right. Many of these people have spent years working in the Landsat program, whether as program managers guiding the satellites from concept to launch, engineers overseeing construction and testing, or scientists interpreting Landsat data.

The next question is harder: Cartographer Betty Fleming discovered a tiny island about the size of a football field using Landsat 1 satellite imagery. Off the coast of what country is Landsat Island?

Landsat Island, I learn, is off the coast of Newfoundland in Canada – and the person who verified its existence almost died while doing so. You can read the full story here, but suffice to say, it involved a scientist who got swatted at by a polar bear while being lowered onto the island by helicopter. (Spoiler alert: he survived.)

I’m impressed when several teams get that question right too. The third one, though, I don’t need Google to answer.

“Set in 1973, a year after Landsat 1’s launch, what origin story movie did Landsat play a role to locate an uncharted island in the Pacific?”

The 2017 film “Kong: Skull Island” features Marc Evan Jackson, who plays a NASA scientist named “Landsat Steve.” Jackson also partnered with NASA in 2020 to narrate the “Continuing the Legacy” video series. Nearly every team gets this question right.

In a break between rounds, I chat with a team that named itself ERTS-1. At the table is Steve Covington, principal systems engineer for USGS’ National Land Imaging Program.

“I’m feeling great about launch on Monday,” he said. “It’s going to be cloudy, but I think it’ll be very successful. I’m excited about Landsat 9 getting up there and joining Landsat 8 — and giving Landsat 7 a well-deserved rest.”

Landsats 8 and 9 will work together to cover all of Earth’s land masses every eight days — cutting in half the current 16-day coverage time. Covering the Earth more frequently means scientists can detect changes that happen over a few days instead of a few weeks, giving them more insights into what’s happening on our planet’s land surface.

The group’s enthusiasm for the mission and the launch spills over into the festive atmosphere of the game. And at the end of the night, the grand prize goes to the New Originals — a group of Landsat communicators, educators, and scientists that includes Landsat 9’s project scientist, Jeff Masek.

Events like trivia night highlight the celebration and camaraderie surrounding a satellite launch, which, for many, often represents a pivotal moment, a demonstration of many years of hard work. When Landsat 9 launches Monday, it will continue a legacy that stretches back nearly 50 years, and includes decades of human stories as well as scientific ones — an achievement that is anything but trivial.

 

 

‘The most exciting beep I’ll ever hear’

 
Mechanical and electrical support equipment for NASA’s Landsat 9 observatory being processed inside the Integrated Processing Facility at Vandenberg Space Force Base in California, on June 24, 2021. The equipment includes a secondary payload adapter and flight system for a group of microsat payloads, called CubeSats, that will launch with Landsat 9 as secondary payloads.
Mechanical and electrical support equipment for NASA’s Landsat 9 observatory being processed inside the Integrated Processing Facility at Vandenberg Space Force Base in California, on June 24, 2021. The equipment includes a secondary payload adapter and flight system for a group of microsat payloads, called CubeSats, that will launch with Landsat 9 as secondary payloads. Credit: NASA / Jerry Nagy

By Jessica Merzdorf Evans // NASA GODDARD SPACE FLIGHT CENTER, MARYLAND //

When the Landsat 9 satellite launches to space next week, it won’t be going alone. NASA is partnering with the U.S. Space Force to launch four CubeSats — miniature satellites — on the same Atlas V rocket that’s taking Landsat 9 to its orbit 438 miles above Earth.

While some of the missions sport adorable names — they’re dubbed CUTE (Colorado Ultraviolet Transit Experiment), CuPID (Cusp Plasma Imaging Detector), and Cesium Satellites 1 and 2 — these little satellites are pioneering some serious science and technology.

The four CubeSats are mounted on a ring-shaped frame, called the ESPA, or the “Evolved Expendable Launch Vehicle Secondary Payload Adapter.” (The program’s name, EFS, stands for ESPA Flight Systems.) The ESPA will ride with Landsat 9 inside the top section of the rocket, the payload fairing. After the rocket’s second stage, called the Centaur, safely boosts Landsat 9 to its orbit, it will drop to a lower orbit and send the CubeSats on their way.

“This is a pathfinder mission for NASA, so the process for doing it was undefined,” said Theo Muench, a NASA engineer and the partnership’s program manager. “NASA has never flown an ESPA ring with secondary payloads inside the fairing before, so we had to work with all our stakeholders to invent a plan to fly.”

Rideshare programs aren’t new — programs like NASA’s CubeSat Launch Initiative (CSLI) regularly coordinate rides for small satellites with larger missions. The Air Force, Space Force and commercial launch providers like SpaceX have let satellites tag along on their missions too. But the new EFS partnership provides access to more missions between NASA and the Space Force, increasing the number of options available to mission designers.

“This program is a big cost-saver, because a lot of times you can buy an ESPA ring for a fraction of what it would take to buy a small launch vehicle,” said Maj. Julius Williams, chief of the U.S. Space Force’s Mission Manifest Office, or MMO. The MMO’s goal is to seek out launch partnerships with other agencies. “If someone were to procure a satellite launch vehicle on their own, they wouldn’t use as much of the vehicle capability, on top of the fact that they’re using those funds themselves. This partnership saves taxpayer dollars for other programs.”

Two of the hitchhikers, CUTE and CuPID, are science satellites. CUTE is funded by NASA and managed by the University of Colorado’s Laboratory for Atmospheric and Space Physics (LASP) in Boulder, Colorado. The little satellite will carry a space telescope and a spectroscope, measuring near-ultraviolet light to learn about the atmospheres of planets outside our solar system. Specifically, they’ll be looking at escaping gases from “hot Jupiters” – large planets that orbit close to their parent stars. The team will study how these planets lose atmosphere in their suns’ heat, to better understand how likely atmospheres are to survive on all types of planets.

University of Colorado graduate student Arika Egan leads installation of the CUTE CubeSat into the EFS dispenser system at Vandenberg Space Force Base on July 23, 2021. Credit: NASA / WFF
University of Colorado graduate student Arika Egan leads installation of the CUTE CubeSat into the EFS dispenser system at Vandenberg Space Force Base on July 23, 2021. Credit: NASA / WFF

CUTE is smaller than the average space telescope, and the team is excited to push the envelope technologically as well as scientifically. “The cool story of CUTE is how all the ambitions we packed in at the beginning came together in the end,” said project scientist Brian Fleming, a researcher at the University of Colorado-Boulder. “In the early days, it was a big challenge to get the science performance we needed from this little ‘cereal box.’ We approached it with a little bit of fun—every time we came up with a new crazy idea, we said ‘okay, let’s try that too.’ That approach really paid off, and CUTE can do some amazing things for its size.”

The second science CubeSat, CuPID, will take measurements closer to home — this mission will study the interactions between the Sun’s plasma and Earth’s magnetosphere, or the protective “bubble” formed by Earth’s magnetic field that keeps harmful solar radiation away from the surface.

(To learn more about CuPID, check out their spotlight here.)

Cesium Satellites 1 and 2 are experimental satellites owned by CesiumAstro, an aerospace company that specializes in space communications. These CubeSats will test an antenna technology called an active phased array, which uses electromagnetic interference to move a signal beam without moving the physical antenna. This technology could make future satellites easier to use and repair, with fewer moving parts to break down. “Riding along with Landsat 9 provides Cesium Mission 1 with the opportunity to test their products in space before selling them to consumers,” said Scott Carnahan, Cesium Mission 1 manager.

Delivering the CUTE satellite marked a bittersweet moment, since it’s been “this presence with us for almost four years,” said CUTE lead investigator Kevin France, an associate professor at the University of Colorado.

“Right now, I’m most excited to hear the first beep back from the satellite on launch day,” Carnahan said. “When you go through all the tribulations to get a satellite up to orbit, you want it to get up there and be safe. That will be the most exciting beep I think I’ll ever hear.”

Landsat 9 is a partnership between NASA and the U.S. Geological Survey.

Meet Landsat 9

An artist’s conception of the Landsat 9 spacecraft, the ninth satellite launched in the long-running Landsat program, high above the agricultural fields in California’s Central Valley and the Western US. Credit: NASA’s Goddard Space Flight Center / Conceptual Image Lab

by Jenny Marder //VANDENBERG SPACE FORCE BASE, CALIFORNIA//

It’s less than four days before the planned launch of Landsat 9, and the perfect time to learn about this amazing satellite and the nearly 50-year-old Landsat program. Did you know:

Landsat gives us the longest continuous space-based record of planet Earth.

Since the first satellite launched in July 1972, the mission’s eight satellites provide five decades of information about our planet’s land and atmosphere. And they show us how our planet is changing. This will continue with the Landsat 9 launch, providing more data and higher imaging capacity than past Landsats.

Landsat 9 will carry two science instruments …

The Operational Land Imager 2, or OLI-2, sees at a spatial resolution of 49 feet for its panchromatic band, which is sensitive to a wide range of wavelengths of light, and 98 feet for the other multispectral bands. Its image swath is 115 miles wide, with enough resolution to distinguish land cover features like urban centers, farms and forests.    

The Thermal Infrared Sensor 2, also known as TIRS-2, measures land surface temperature in two thermal infrared bands using principles of quantum physics to measure emissions of infrared energy.

… and it will orbit the Earth at an altitude of 438 miles. 

That’s roughly the distance between Dallas and Memphis.

Landsat has shown us how dynamic the planet is in response to human activities.

“When you grow up in an area, you don’t really notice the changes that occur over years and decades,” Dr. Jeff Masek, NASA Goddard’s Landsat 9 Project Scientist, told Dr. Alok Patel in December 2020 for PBS’s NOVA Now podcast. “But when you run the movie in fast motion, suddenly we see all these changes: urbanization and changes in forest management, areas where agricultural irrigation suddenly goes into desert environments.”

Watch this video for a Landsat roadtrip through time.

You’ll learn about the first game-changing launches in the 1970s, the advent of natural color composite images in the 1980s, the increased global coverage in the 1990s, the move to free and open data archives in the 2000s, the modern era of Landsat observations in the 2010s, and now, the launch of Landsat 9 in 2021.

And follow us here and on Twitter @NASAExpeditions this week as we count down to Landsat 9’s launch!

Chasing Satellites with Jacques Cousteau

acques Cousteau and his team of expert divers were a key part of the success of the 1975 NASA-Cousteau Bathymetry Experiment. In this photo from left to right: Bernard Delemotte, Chief Diver; Henri Garcia; Jean-Jérome Carcopin, and Jacques Cousteau. Photo credit: NASA
Jacques Cousteau and his team of expert divers were a key part of the success of the 1975 NASA-Cousteau Bathymetry Experiment. In this photo from left to right: Bernard Delemotte, Chief Diver; Henri Garcia; Jean-Jérome Carcopin, and Jacques Cousteau. Photo credit: The Cousteau Society (preserved as large format photo at NASA’s Goddard Space Flight Center)

By Laura Rocchio, Goddard Space Flight Center

Leaving from Nassau on a Tuesday night in August 1975, Jacques Cousteau and his team set out on the Calypso for a three-week expedition designed to help NASA determine if the young Landsat satellite mission could measure the depth of shallow ocean waters.

For days, the Calypso played leapfrog with the Landsat 1 and 2 satellites in the waters between the Bahamas and Florida. Each night, it sailed 90 nautical miles to be in position for the morning overpass of the satellite.

Ultimately, research done on the trip determined that in clear waters, with a bright seafloor, depths up to 22 meters (72 feet) could be measured by Landsat.

The primary test site for the expedition was just west of the Berry Islands on the northern edge of the Great Bahama Bank. The location was chosen as the prime testing site because it gradually changed depth from one meter to deep ocean in a short north-south span (25 nautical miles). This natural-color Landsat 8 image acquired on March 23, 2019, shows where the northern Great Bahama Bank meets the deep ocean. Image credit: NASA/USGS Landsat
The primary test site for the expedition was just west of the Berry Islands on the northern edge of the Great Bahama Bank. The location was chosen as the prime testing site because it gradually changed depth from one meter to deep ocean in a short north-south span (25 nautical miles). This natural-color Landsat 8 image acquired on March 23, 2019, shows where the northern Great Bahama Bank meets the deep ocean. Image credit: NASA/USGS Landsat

This revelation gave birth to the field of satellite-derived bathymetry and enabled charts in clear water areas around the world to be revised, helping sailing vessels and deep-drafted supertankers avoid running aground on hazardous shoals or seamounts.

“It was a tremendous example of how modern tools of scientists can be put together to get a better understanding of this globe we live on,” the Deputy NASA Administrator, George Low, said of the joint Cousteau-NASA expedition in a 1976 interview.

But it couldn’t have happened without the world’s most famous aquanaut, his team of expert divers, and the Calypso.

Astronauts and Aquanauts Together

The ocean’s vastness made Cousteau an early supporter of satellite remote sensing.

Cousteau, by then a decades-long oceanographer, was keenly aware that ocean monitoring from above would be necessary to understand the ocean as part of the interconnected Earth system and to raise the awareness requisite for protecting the sea. There was a growing recognition in the 1970s that helping the planet required understanding the planet.

“Everything that happens is demonstrating the need for space technology applied to the ocean,” Cousteau said during a 1976 interview at NASA Headquarters.

George Low, the Deputy NASA Administrator, himself a recreational diver, connected Jacques Cousteau with former Apollo 9 and Skylab astronaut Russell Schweickart. Schweickart was heading up NASA’s User Services division and both he and Cousteau were looking for ways to advance Earth science.

At the time, it was theorized that the new Landsat satellites might be useful for measuring shallow ocean waters. New deep-drafted supertankers were carrying crude oil around the globe, and to avoid environmental catastrophes it had become important to know where waters in shipping lanes were less than 65 feet (20 meters).

For this experiment, Landsat data was downlinked to NASA Goddard Space Flight Center in Greenbelt, Maryland where it was processed into depth contour data. This was uplinked to the Applications Technology Satellite-3 (ATS-3) and then sent via Very High Frequency (VHF) relay to a VHF receiver system that had been installed on the Calypso for an earlier 1974 experiment in the Gulf of Mexico. Image credit: NA
For this experiment, Landsat data was downlinked to NASA Goddard Space Flight Center in Greenbelt, Maryland where it was processed into depth contour data. This was uplinked to the Applications Technology Satellite-3 (ATS-3) and then sent via Very High Frequency (VHF) relay to a VHF receiver system that had been installed on the Calypso for an earlier 1974 experiment in the Gulf of Mexico. Image credit: NASA

To establish if Landsat could accurately measure ocean depth from space, simultaneous measurements from ships, divers and the satellite were needed.

Schweickart knew a coordinated bathymetry expedition was an essential step. He had honed his diving expertise while training for his Skylab mission in NASA’s water immersion facility and was enthusiastic about scuba work. Teaming with Cousteau was a natural fit.

Chasing Satellites

An elaborate experiment was designed to determine definitively if multispectral data from the Landsat satellites could be used to calculate water depth. The clear waters of the Bahamas and coastal Florida were selected as the test site.

The experiment design involved two research vessels, the Calypso and Johns Hopkins University Applied Physics Lab’s Beadonyan, being in position, or “on station,” when the Landsat 1 and 2 satellites went overhead on eight different days (four consecutive days on each of two weeks).

The overall concept was simple: the research ships would use their fathometers to measure water depth at the exact same time that the satellite flew overhead and then those measurements would be compared (the simultaneous measurements eliminated any environmental or atmospheric differences that could have complicated comparisons). But realizing that plan took extraordinary coordination.

A detail from the planning map used for the 1975 NASA-Cousteau Bathymetry Experiment showing the Berry Islands. The hatched lines show the location of Landsat scene edges. Click on image for full map. Image credit: NASA
A detail from the planning map used for the 1975 NASA-Cousteau Bathymetry Experiment showing the Berry Islands. The hatched lines show the location of Landsat scene edges. Image credit: NASA

As the Landsat satellite flew overhead, Cousteau and his team of divers made a series of carefully timed measurements of water clarity, light transmission through the water column, and bottom reflectivity. This was done both near the Calypso and at two sites 60 meters from the Calypso using small motorized Zodiac rigid inflatable boats.

To make the light transmission measurements, two teams of divers had to use a submarine photometer to measure light at the water’s surface, one meter under the water and in 5-meter increments to the bottom (down to 20 meters).

The divers had to hold the photometer in a fixed position looking up and cycle through four different measurements. They also used specially filtered underwater cameras to measure bottom reflectivity (assisted by gray cards for reference). Everything was carefully timed. Schweickart and President Gerald Ford’s son Jack helped with these underwater measurements.

To make the precision measurements, the skill of these divers – including Cousteau’s chief diver, Bernard Delemotte – was essential.

“I was in charge of the divers,” Delemotte explained in a recent interview. “We were very convinced that we could do serious work together [with NASA].”

Before the satellite overpass, the Calypso and Beayondan were in position, anchored side-by-side, and ready to make all specified measurements.

“Two small Zodiacs left from the Calypso just before the satellite passage,” Delemotte recalls.

The Zodiacs stationed themselves 200 feet (60 meters) from the Calypso, and at the moment that the satellite was overhead someone on the Calypso would call to the divers through the portable VHF radio: “Go now!”

The divers would then start the series of prescribed measurements.

Using these measurements, scientists developed mathematical models describing the relationship between the satellite data and water depth, accounting for how far the light could travel through water, and how reflective the ocean floor was.

“Particular thanks” was given to Cousteau’s team of divers in the experiment’s final report “for their dedication and expertise in the underwater phases of the experiment, without which, measurements of key experimental parameters could not have been made.”

The diving prowess of Cousteau, Delemotte, and the Calypso crew added inextricably to the realm of satellite-derived bathymetry. Because of data collected during the NASA-Cousteau expedition, charts in clear water areas around the world were updated, making sea navigation safer. It was the precision measurements made by Delemotte and Cousteau’s team of divers that made bathymetry calculations for those chart updates possible.