Tag: ocean

People of PACE: Gary Davis Leads His Team Through Engineering Feats

Gary Davis is the mission systems engineer for PACE at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

What is your favorite ocean or atmospheric related book or movie?

I don’t know if it’s classified as a book, but I do like the Edgar Allan Poe story “A Descent Into the Maelstrom.” My favorite ocean movie? I really liked the movie “Master and Commander.” It’s not really an ocean movie, but a lot of it takes place on sailing ships, and they do have a naturalist in that movie who researches plants, insects, and other creatures.

What is your background?

I went to engineering school at the University of Virginia, got a bachelor’s degree in aerospace there, and then went to Princeton and got a master’s in mechanical and aerospace engineering. Essentially right out of school, I came to Goddard. I started off in the propulsion branch, and I worked on the TRMM mission – Tropical Rainfall Measuring Mission – and then the MAP mission – Microwave Anisotropy Probe. That’s a mouthful. Then I worked on the Solar Dynamics Observatory, I worked on the MMS mission – Magnetospheric Multiscale, another mouthful – and then OSIRIS-REx and now PACE.

A man, seen from his shoulders up, takes up a majority of the picture. He is wearing a white clean suit which covers over his head, and also a white mask that covers his nose and mouth. He has glasses on. Behind him is the PACE spacecraft which is very large and covered in wires and other metallic materials.
Gary with PACE Observatory in SCA Cleanroom. Image Credit: Dennis Henry

What is your role in PACE?

For PACE, I’m the mission systems engineer, so I’m the chief engineer on the project. I have a great team working with me to hopefully make sure it all works.

What are you most looking forward to during launch?

I am most looking forward to the moment when we get the telemetry that the spacecraft is alive and is stable and pointing the solar arrays at the sun. That’s the most critical part for us, is to make sure that the spacecraft has survived the rigors of launch, and that it knows what to do and is pointed in the right direction. So that’s a huge first step for us.

And once that’s all clear, what are you most looking forward to post-launch?

I want to see that first picture. The instrument folks call it first light, and I’m just really excited to see what PACE’s instruments can do. We’ve been testing them on the ground for all these years, but they’re not looking at anything really, just the laser light that we shine in or the ceiling of the cleanroom. When the Ocean Color Instrument is able to see the ocean and the polarimeters see the aerosols in the atmosphere, it will be amazing to get that first image.

Since OCI will be looking at all these different colors of the ocean, what is your favorite color and why?

That’s an easy one. My favorite color is British Racing Green and the reason why is I’m a Formula One fan and my favorite team (though they don’t race anymore) is Lotus. Way back in the day, most of their cars were painted British Racing Green, so I’ve always loved that color. It’s a dark green, and it’s very fast.

Four men stand in a picture. All four are holding trombones in their hands. From left to right, the second man is Gary Davis. He wears a light blue long-sleeved button up shirt and has protective headphones around his neck. The men he is standing next to are all wearing military uniforms with red jackets, white belts, and black pants.
Gary with U.S. Marine Band Trombone Section. Learn more here. Image Credit: U.S. Marine Band

What advice would you give to aspiring engineers who want to someday work on NASA satellites?

The obvious answer that a lot of people give is “study this science or study that math or take that engineering class” and I kind of go in the opposite direction. For folks who want to work on NASA projects in science or engineering, they’re probably already very strong in science and engineering, so they don’t need any more of that. My advice would be to study and be trained as much as possible in human skills, leadership, team-building, and how to work as part of a team. Especially in today’s world, with so many virtual ways to communicate, your team might not be co-located with you. The better communication skills you have and the better you can get an entire team to work efficiently with you, that means a lot. For any big project, you need multiple people, and even with great people, nobody can do it by themselves – you need a whole team.

What’s a fun fact about yourself, something that a lot of people might not know?

Three men stand in the picture. All are holding euphoniums in their hands. From left to right, Gary is the third man in the picture. He is wearing a red sweater and has a red Santa hat on. The man in the middle also wears a red sweater and has a green holiday had on. The man to the left is wearing a military outfit with a red jacket and black pants. They are standing in a large auditorium and wreaths can be seen hanging in the background.
Gary with other double bell friends at Tubachristmas Kennedy Center. Image Credit: A nice Tuba Player

I’m a trombone player, amateur. I did buy a euphonium so I can play it once a year in Tubachristmas, which is super fun because we get to play the melody which you don’t usually get as a low brass player. So, for one night a year, I’m like a quasi-tuba player and it’s really fun.

 

 

What’s one catch-all statement describing the importance of PACE?

PACE is going to teach us answers about the ocean that we haven’t even been able to ask the questions for yet. It’s going to show us stuff that we don’t even know that we don’t know yet.

Header image caption: Gary with PACE Observatory during PACE Family Day. Image Credit: Dennis Henry

By Erica McNamee, Science Writer at NASA’s Goddard Space Flight Center

People of PACE: Ivona Cetinić Studies the Ocean’s Microscopic Organisms

Ivona Cetinić is a biological oceanographer in the Ocean Ecology Lab at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

What is your favorite ocean or atmospheric related book or movie?

I’m a science fiction fan. Definitely “Abyss.” I don’t know why, but it’s been my favorite ever since I was a kid. I’m sure there are better ones, but it’s the only one that comes into my head movie wise. For a movie it was always, always, always “Abyss.”

What is your background? What do you do for PACE?

The image is primarily taken up by the large trunk of a tree on the right side. The left side of the image shows the background of a forest landscape. A woman is centered in the image, wearing jeans and a black jacket. She is hugging the trunk of the tree, but the tree is much larger than her and she cannot fit her arms around the trunk.
Phytoplankton cannot be hugged, but trees can ?. Image Credit: Mary Jane Perry

I am an oceanographer. I am interested in phytoplankton community structure and how it interacts with the environment, and also how the environment interacts with phytoplankton community structure. That’s how I ended up developing better tools to study phytoplankton.

For PACE, I am in charge of anything that has to do with biogeochemical processes in the oceans. Not just phytoplankton, but also the elements (such as carbon) and energy that phytoplankton move around, and other types of carbon, sediment, or organic material that float around the ocean. So, I take care of those algorithms and make sure that they look nice and pretty once we launch.

What are you most looking forward to during launch?

The launch itself, since I have never been to a single launch. So I’m excited for the countdown, and being surrounded by family, friends, and colleagues, and everybody enjoying that moment.

What are you most looking forward to post launch?

The first light images and the first data. I’m looking forward to getting to start playing with the data as soon as I can get my hands on it. We’ve been testing algorithms and I just want to get some real data!

The image is comprised of four of the same phytoplankton, each taking up one quadrant of the image. The phytoplankton is shaped like a hexagon, and each corner of the hexagon has an additional spike coming off of it. They look slightly like snowflakes. The hexagon and spike parts are bright white colored, except the bottom left phytoplankton is more of a dark blue color. Inside the middle of the hexagon is an orange color.
Microphotographs of phytoplankton species Dictyocha speculum. Image credit: Fisheries and Oceans Canada, Dalhousie University, Rajashree Gouda

Do you have a favorite phytoplankton?

I shouldn’t have favorite children! But there is one that I really like a lot – it’s called Dictyocha speculum. It’s really cute. This “guy” looks like a little star, and to me looks a little bit like the star on top of the PACE logo.

Since PACE will be looking at all these different colors of the ocean, do you have a favorite color and why is it your favorite color?

I think you’ll see me in black all the time, which isn’t a color. It’s really hard to define color because the color is dependent on the thing as well as the light that is bouncing off that thing. And when something is black, that means that eats up everything, all the light. There’s nothing coming back towards your eyes, that’s what black is. I think it just kind of goes back to my teenage years everyone was comfortable person in black. But when it comes to real colors, probably purple, lilac, bluish.

What advice would you have for aspiring oceanographers who are interested in working for NASA?

Never give up. Never surrender. Really jump at any opportunity that opens up to you, just because you will never know where it’s going to lead. And it might not lead right to where you want to go, but it’s much better than sitting in one spot and thinking “Oh, what would be happening, where would I be if I didn’t take that opportunity?” Just try to jump on any opportunities out there. I was lucky to have the doors open every time and I was just jumping in everything that was available to me. I think that’s the route that got me to NASA.

A woman is centered in the image wearing a bright red outfit with white, black, and blue patterns and designs in circular shape on the back of her outfit. The woman has down black hair with blue streaks through it. She is carrying a drum that rests on the top of her head. The drum has the same pattern of red, black, white, and blue colors on its face.
Ivona carrying her drum during one of the performances of Batala Washington. Image Credit: Robert Werner

What is a fun fact about yourself? Something that people might not know about you?

I like music a lot, and I play many instruments. Currently, I play drums in an all-women, Afro-Brazilian band.

What is one-catch all statement describing the importance of PACE?

PACE will give us a view of the ocean and atmosphere that we have never had before. It opens up so many possibilities that we don’t even know about. I think PACE is going to give us so much more insight than we expect about the ocean and the atmosphere and interactions between them.

Header image caption: Ivona happily posing with the PACE observatory. Image Credit: Dennis Henry

By Erica McNamee, Science Writer at NASA’s Goddard Space Flight Center

People of PACE: Corrine Rojas Helps Connect Science to Engineering and Back

Corrine Rojas is a scientific programmer in the ocean ecology lab at NASA’s Goddard Spaceflight Center.

Before we dive into your work with PACE, what is your favorite ocean- or atmosphere-related book or movie?

I’m a big fan of ridiculous sci-fi/horror movies, and when it comes to the depths of the ocean, Sphere (1998) is one of my favorites in that genre. It’s a psychological thriller with everything you’d ever want – logistically impossible ocean research vessels, Hollywood science, aliens, spooky deep-sea fish, and even Queen Latifah! 

Corrine stands to the left of the image in a nacy blue polo and black pants. Directly behind and to the right of her is Optimism. The rover has large black wheels and it's main frame is covered in several mechanical pieces and wires. The "face" of the rover is on it's left side, still to the right of Corrine.
A picture of Corrine Rojas and the Perseverance Rover’s twin on Earth, Optimism, at NASA’s Jet Propulsion Laboratory in Southern California. Optimism is a vehicle system test bed used for safety testing of moves and navigation scenarios on Earth before performing them on Mars. (more info here: https://mars.nasa.gov/resources/26356/improved-optimism/) Image Credit: Corrine Rojas

What is your background? What do you do for PACE?

Before PACE, I worked on a lunar mission called Lunar Reconnaissance Orbiter, and then a couple of Mars missions including the Curiosity and Perseverance rovers. And now I’m here, back down to Earth! I’m doing science operations for Earth missions that look at ocean ecology. And there is just so much life to track here! Doing science operations, I’m a liaison between the engineering team that will control the spacecraft and the scientists that will be monitoring the atmosphere and the ocean ecology. I have to have a background in both science and engineering. I moved to Maryland from Arizona, and before PACE I was working on the Jezero Delta on Mars, near where the Perseverance rover landed. So, I’m coming in from two different deserts, and I now live much closer to the ocean flora and fauna looking at the ocean from space for a living. I feel like a little alien!

 

What does programming and science operations entail?

As a programmer, I’m developing tools that will tell the spacecraft where to look. Once we’re in orbit, I’ll make sure that the science team gets their priority observations. For example, if someone’s out on a research cruise collecting samples in the open sea, we can time the spacecraft to take pictures overhead which will be a really good data point for them. We’re making sure those scientists are getting what they want and packaging these spacecraft commands in a way that also works with the mission operations schedule.  

Corrine is standing centered in the image with one hand raised into the air. She is on a large plane of warped ground, cooled lava, which is a dark black and grey color. The sky above her is peeking through as blue at the horizon, but is primarily a cloudy gray color.
Corrine Rojas doing field work on Mauna Loa, Hawai’i using orbital data maps to understand the volcanic origins of the Jezero Crater floor on Mars that the Perseverance rover has been investigating. (more: https://www.nasa.gov/missions/mars-2020-perseverance/perseverance-rover/nasas-perseverance-makes-new-discoveries-in-mars-jezero-crater/) Image Credit: Corrine Rojas

What advice would you give other early career scientists or other people looking to get into science operations or finding their space in… well, space?

I didn’t always see myself working at NASA. I studied political science for a few years before coming into geography and that’s my academic background – modern day geography translated into programming.

But really, what has opened the door to having this as a career, is my love for maps. Creating and reading maps has always been a passion of mine. And that passion translated to creating maps of the surface of the Moon and the geology of Mars through NASA missions. I’m grateful that NASA needs a variety of disciplines to make a mission possible.

NASA has jobs that range from computer programmers like me, to mechanical engineers and scientists, but also writers and photographers. Even finance folks. It takes a lot of different disciplines to make a NASA mission work. And if you find something that you really enjoy, there’s probably going to be a related job that can take you to working on a mission.

Corrine stands to the left of the image, wearing a white clean suit that covers her whole body including torso, arms, and head. She is seen only from the waste up in this picture and is crossing her arms across her chest. She also wears a white mask to cover her nose and mouth. To the right of her is the PACE spacecraft, which takes up a majority of the image. It is primarily a silver color and much of the spacecraft is covered in foil.
A portrait of Corrine Rojas all bunny suited-up in front of the PACE spacecraft a few weeks before it shipped to the Kennedy Space Center in Florida for launch. Image Credit: NASA’s Goddard Space Flight Center/Denny Henry

What are you most looking forward to post-launch?

That’s when my job really starts! After the spacecraft is commissioned, we’ll start commanding the sensors to take scientific observations. I’m looking forward to working with the world’s best oceanographers and atmospheric scientists, making sure that they’re getting the data they want. Hopefully we’ll have more answers regarding Earth sciences and climatology studies, especially aerosol studies since we don’t have a lot of that data. All this data will help anywhere from fisheries to disaster management and more. Everyone relying on that data is about to get a firehose of information, and I’m excited to see them dig into it.

Corrine stands centered in the image wearing pale mauve colored leggings, a white workout shirt, a green ball cap, and a brown weightlifting belt. She stands by a weight rack, directly behind the bar with her right hand resting on the black bar. She is taking this picture in a mirror using her cellphone which is in her left hand.
At the gym on center at NASA’s Goddard Space Flight Center! Image Credit: Corrine Rojas

What is a fun fact about yourself? Something that people might not know about you?

I’m a newbie, but I weightlift pretty consistently. It’s just something that I enjoy doing that takes me away from the screen and into the present moment. I can just focus on the here and now, and my body getting really strong and staying healthy.

What is one catch-all statement describing the importance of PACE?

PACE is going to help us track the heartbeat of ocean, from a few meters below the sea surface all the way up to the top of the atmosphere.

Corrine is standing centered in the image wearing a blue polo. Her hands are raised slightly up and next to her as if she is presenting something with them. Behind her is the PACE spacecraft, large, cube-like, and primarily a silver color. PACE is sitting behind a glass window separating it from where Corrine is standing.
A quick shot in front of the PACE spacecraft after volunteering for a PACE friends and family event. Image Credit: Corrine Rojas

Header image caption: Corrine Rojas during one of her many walks around Washington, D.C. during cherry blossom season. Image Credit: Corrine Rojas

Erica McNamee, Science Writer at NASA’s Goddard Space Flight Center

Friends & Family Meet PACE

With the towering structure of the spacecraft just behind clear plastic curtains, engineers, scientists, and others who worked on the Plankton, Aerosol, Cloud, ocean Ecosystem mission recently had the chance to see the result of their hard work.

“Your dad does amazing stuff for us. He goes and puts out fires all the time,” Juli Lander, the PACE deputy project manager, said to a teenager waiting with his family to take a picture in front of the satellite.

The spacecraft and its instruments are the culmination of more than eight years of hard work, late nights, and early mornings, she said, and this was their chance to see the finished product right before it traveled to Florida to prep for launch.

“It’s really important for us to let everyone see the great work that their family members have been doing,” Lander said. “Everybody who’s coming through is very excited, even if they’ve been here before.”

A large group of people stand in the foreground of the image, facing away from the camera. They are facing a large metal chamber - the thermal vacuum chamber - which has several grey, metal tubes on the side. The chamber takes up the full top right corner of the image.
At one of the stops on the PACE Friends and Family Day tour at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, guests saw the thermal vacuum chamber where the spacecraft was tested to ensure it could survive in the harsh environment of space. Image Credit: NASA/Kate Ramsayer

More than 550 people came to the PACE Friends and Family day Oct. 28, 2023, at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, where the spacecraft and its Ocean Color Instrument (OCI) were built. They toured the cleanroom where PACE was assembled and tested, including the giant thermal vacuum chamber where it was subjected to the temperature and pressure extremes of space.

They heard from scientists about what insights the satellite will provide about the ocean, atmosphere, and climate, and got to peer through a microscope to see some of the tiny phytoplankton that PACE will study from space.

“We’re showing off the science that we’re doing with PACE,” said Carina Poulin, a scientist and outreach specialist who was helping with hands-on activities during the event. There were puzzles of colorful ocean waters, a PACE-themed card matching game, cultures of green and yellow and pink phytoplankton and more.

The visitors were asking lots of great questions, Poulin said. “They all know someone who works with PACE, so they’re excited.”

Sabrina Sharmin, who started with the PACE team almost seven years ago and is now a systems engineer with OCI, introduced her enthusiastic guests to coworkers, and pointed out highlights of the cleanroom facility.

“This remarkable spacecraft is a result of countless hours of collaborative effort by the entire team, and I am so proud of all of us,” Sharmin said. “It’s a momentous occasion, being able to showcase the project to friends and family.

Header image caption: PACE engineer Sabrina Sharmin, in center in brown shirt, brought friends and family to see the spacecraft at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The anticipation and excitement within our team for launch is unparalleled,” she said. Image Credit: NASA/Kate Ramsayer

Kate Ramsayer, Strategic Communications Lead for Earth Science Missions at NASA’s Goddard Space Flight Center

Six Weeks at Sea: NASA Scientists Double-Check Satellite Ocean Color Data

NASA researcher Joaquin Chaves calls it “ground truthing,” even though land is nowhere in sight.

This spring, Chaves boarded the Atlantic Meridional Transect (AMT) research cruise for six weeks of sampling water and taking measurements as the ship traversed the Atlantic Ocean. His team, based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, uses that information gathered at sea to verify and improve ocean data from an array of Earth-observing satellites and instruments in orbit.

Upcoming satellites like the PACE, or Plankton, Aerosol, Cloud, ocean Ecosystem, mission launching in early 2024, will also use field campaigns like this one to help validate their sensors.

A scientist is crouching in front of a gray tank holding a small brown glass bottle. The scientist is wearing purple latex gloves and a green hard hat to safely perform the research aboard the ship.
Chaves is preparing to conduct scientific research while onboard. He worked around the clock to collect samples that will help check the accuracy of satellite data. Image Credit: NASA/Joaquin Chaves

These sensors start collecting data soon after launch, but it takes time to ensure that those observations are accurate and reflect what is happening back on Earth. One of the best ways to do this is to send scientists like Chaves into the field.

On the spring cruise, Chaves was joined by another NASA Goddard scientist, Harrison Smith.

“It was a lot of work, always intense,” Chaves said. “Even before you sail, you’re setting up. Every day is a work day, there are no Saturdays or Sundays.”

During their time on the cruise, the NASA team collected two types of data to build mathematical models to validate satellite data. Validation is the practice of checking the accuracy of data before it’s processed and used by NASA and its partners.

The first data type was the optical properties of water.

“Ocean color satellites measure visible light,” Chaves said. “We must try to replicate what they measure.”

A scientist is standing under a plastic sheet that serves as a barrier for his experiment station in front of him. The experiment includes several containers of liquid and plastic tubing.
Chaves conducting field experiments and validation. Credit: NASA/Joaquin Chaves

In addition to the optical measurements, the NASA scientists also gathered water samples to measure the abundance of phytoplankton pigments and various forms of carbon.

By the end of the campaign, Chaves had collected 700 samples to process, which he is now analyzing back at Goddard.

Chaves and Smith were just two of the research cruise’s passengers, which also included 25 scientists based in the UK, Europe, Africa, and Latin America. Chaves said it was one of the best field campaigns he’s been on. The researchers connected with others and talked of future collaborations.

“It’s hard work,” he said. “It remains one of my best experiences at sea because of how modern the ship was, well trained the crew were and the officers are and willing to help.”

The AMT program, which started in 1995, allows researchers from all over the world to study the ocean’s biogeochemistry, ecology, and physical properties during voyages between the United Kingdom and the South Atlantic.

Learn more about the AMT cruise here.

Header image caption: A map of where the cruise travelled for six weeks in the Atlantic Ocean. Credit: NASA/Joaquin Chaves

By Sara Blumberg, NASA Oceans Communications Lead at NASA’s Goddard Space Flight Center

NASA’s PACE Spacecraft Assembled, Advances Toward Launch

Although PACE was formally authorized in 2015, its concept has been on the minds of NASA Earth scientists for over 21 years.

In 2023, that concept is now an assembled spacecraft at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. 

This past month, the PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) mission advanced closer to launch, passing a critical review demonstrating final tests for its readiness for observatory integration and testing. PACE will continue preparations for its move to NASA’s Kennedy Space Center in Florida, where it is scheduled to launch in January 2024.

“It’s an absolutely huge achievement for the team after having conceived the PACE system architecture, completed the design, implemented and built all the hardware and software systems,” said Mark Voyton, PACE’s Project Manager.

PACE’s solar array deploying in the Goddard cleanroom. Video by Denny Henry, NASA

Once in orbit, PACE will view the atmosphere and ocean surface from space. It will help scientists learn more about the relationships between phytoplankton and the surrounding environment by measuring how light reflects off the ocean and through the atmosphere.

Before any NASA mission can launch, however, it must go through a series of immersive reviews, called key decision points, to show it can operate in space. Getting to this moment has been a long time coming for the team. 

Since its inception, PACE has faced many challenges. Last year, for example, one of PACE’s polarimeters, HARP2, experienced parts failures during testing, forcing the team to reevaluate several of its design concepts. Budget-wise, the mission also experienced hurdles related to the global Covid-19 pandemic.

Testing and moving the PACE spacecraft. Image by: Denny Henry, NASA

“It is somewhat difficult to wrap my head around being fewer than 300 days from launch.  All the ideas and concepts from the past decade have been turned into reality! It’s been a long strange trip, but one we don’t regret pursuing,” said PACE lead scientist Jeremy Werdell.

PACE team members have remained busy in their preparations. Late last year, the team integrated all three of its scientific instruments onto the spacecraft, thus forming the PACE observatory. The mission most recently also completed testing the deployment of PACE’s solar array.

Next steps for the team will focus on final integration and testing activities at Goddard. This includes vibration and acoustics tests that simulate the launch environment, as well as several months of thermal vacuum tests that simulate the environment of space. 

“Once these activities are complete, the observatory will be trucked to Kennedy for additional testing and integration onto the launch vehicle,” Werdell said. 

Header image caption: PACE tech Jean Arnett is cleaning the Aronson table.  The Aronson table is used to tilt the spacecraft over like in the photo below. Image by: Denny Henry, NASA

By Sara Blumberg, NASA Oceans Communications Lead at NASA’s Goddard Space Flight Center

The Journey of a Carbon Atom: From Space, NASA’s PACE Mission Detects Carbon in the Sky, Land, and Sea

Whether in plants or animals, greenhouse gases or smoke, carbon atoms exist in various compounds as they move through a multitude of pathways within Earth’s system. That’s why NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission – scheduled to launch in January 2024 – was designed to peer down at Earth from space to see those many forms of carbon in a way no other satellite has done before by measuring colors not yet seen from the vantage point of space.

“PACE is standing on the shoulders of some giants, but previous and current satellites are limited in how many colors of the rainbow they can actually see,” said Jeremy Werdell, project scientist for the PACE mission at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Although one of the primary goals of the mission is to measure the colors on the ocean surface, in the 420 miles (676.5 kilometers) between PACE in orbit and sea level are parts of the complex carbon web that the satellite will also be able to monitor.

The connection between major wildfires and the subsequent explosion of phytoplankton production is an example of the events NASA’s upcoming Plankton, Aerosols, Clouds, and ocean Ecosystem (PACE) mission will help investigate. PACE’s suite of instruments will allow scientists to get a clearer picture of carbon as it links land use and fires, atmospheric aerosols and marine communities. Credit: NASA’s Goddard Space Flight Center

Atmosphere

From PACE’s location in space, one of the nearest forms of carbon to detect could be the wispy plumes of smoke and ash rising into the atmosphere from fires. Carbon is a key building block of much life on Earth, including plant life. When burned, the vegetation’s carbon-based molecules transform into other compounds, some of which end up as ash in these plumes.

The instruments on PACE will be able to monitor these smoky clouds, as well as other atmospheric aerosol particles, measuring their characteristics including the relative amount of smoke in different places. Combinations of these measurements made by PACE’s two companion polarimeter instruments, SPEXone and the Hyper-Angular Rainbow Polarimeter-2 (HARP2), and the detailed color measurements of the smoke made by the Ocean Color Instrument (OCI) will also help scientists identify what was burnt.

“Each instrument brings something different,” said Andy Sayer, PACE’s project science lead for atmospheres at NASA Goddard. “Putting them all together though, you’re getting the most information.” Sayer is also a senior research scientist for the University of Maryland Baltimore County.

These measurements help scientists understand more about the balance between the incoming energy from the Sun, the outgoing energy from Earth, and where it may be absorbed in between by things in the atmosphere like these smoke plumes. Even at a local level, PACE can provide information about how smoke affects air quality, impacting communities that may be near fires.

Land

Peering through the smoke particles and other aerosols, PACE can also tell us about the health of terrestrial plants and trees. Even after a devastating wildfire, fresh green plant life begins to grow and thrive. With more spectral bands and colors to see from the upcoming satellite, scientists will be able to understand what kinds of plants are recovering from fires over the years.

“In a time where we’re experiencing unprecedented climate change, we need to be able to understand how global vegetation responds to its environment,” said Fred Huemmrich, research associate professor at the University of Maryland, Baltimore County, and a member of the PACE science and applications team.

PACE will be able to monitor the different shades of colors in vegetation, and plant color can be an indicator of health. Just as house plants begin to fade to yellow if they haven’t been watered enough, plant life around the globe changes color as it experiences stress. Healthy plants take up carbon in the form of carbon dioxide as part of photosynthesis, while unhealthy plants that can’t complete photosynthesis leave the carbon dioxide roaming around the atmosphere. Given that carbon dioxide is a greenhouse gas, these measurements also play a significant role in understanding climate change in greater detail.

By measuring a full spectrum of color, PACE will view tiny changes in pigment to detect how plants are responding to stressors, helping scientists learn whether they are utilizing the surrounding carbon or not. Previously, these colors were primarily viewed in field studies of specific areas. Stressors like droughts were inferred using weather data, but covering large expanses was difficult.

“For the first time, we’ll really be able to look at changes in the health of plants over the globe,” Huemmrich said. “It will dramatically improve our understanding of how ecosystems function and how they respond to stress.”

Ocean

From plants on land to organisms in the ocean, PACE will view the expanses of water on Earth to measure phytoplankton – the P in its name. With its ability to measure a wide spectrum of colors, PACE will now not only be able to see more across the surface of the ocean but will also help scientists differentiate between phytoplankton species.

“It’s like you were making a painting with really coarse brushes, and now you have thin, fine brushes that help explain so much more in greater detail,” said Ivona Cetinić, an oceanographer in the Ocean Ecology Lab at NASA Goddard.

Phytoplankton, small organisms that live on the surface of the ocean, play a critical role in the food chain and the global carbon cycle. Each type of phytoplankton provides a different pathway in that expansive web of routes that carbon can take, all depending on the characteristics of the plankton. One pathway may lead to the carbon becoming food for a larger species, while another may lead to carbon becoming waste, sinking deeper into the ocean.

Scientists conducting field work have found that types of phytoplankton vary slightly in color and have identified these phytoplankton on small scales. PACE’s ability to measure a full spectrum of color will help scientists tell the difference between phytoplankton on a global scale by seeing more of these colors, deepening the understanding of carbon pathways and quantities.

Though one of PACE’s key goals is to view the ocean, its line of sight looks over the atmosphere and land as well. With these expansive observations, and the massive quantities of data collected, PACE provides the ability to see in what ways the atmosphere, land, and ocean are connected, including with the complex web of carbon pathways. 

“I’m energized for this opportunity for discovery that this observatory is offering,” Werdell said. “I have every expectation the world is going to do great things with these data.”

By Erica McNamee, Science Writer at NASA’s Goddard Space Flight Center

Observatory, assembled!

The Ocean Color Instrument (OCI) is integrated onto the PACE spacecraft in the cleanroom at Goddard Space Flight Center. Credit: NASA’s Goddard Space Flight Center.

The PACE satellite now has all three of its scientific instruments attached to the spacecraft, as the integration crew bolted the Ocean Color Instrument into place with its two polarimeter neighbors.

With the assembly completed Nov. 21 at NASA’s Goddard Space Flight Center, the team will now be working on the electronic and other connections between the different components of the satellite, then putting the complete observatory through tests to make sure it can work in the harsh environment of space.

By Kate Ramsayer, Science Writer at NASA’s Goddard Space Flight Center

NASA’s PACE Mission Undergoes Milestone Testing

NASA’s PACE mission, which will provide a major boost to scientists studying Earth’s atmosphere and ocean health, completed a milestone test in October at the agency’s Goddard Space Flight Center in Greenbelt, Maryland.

The Ocean Color Instrument (OCI) on the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission passed thermal vacuum tests to ensure it can withstand the harsh space environments.

As we prepare the Plankton, Aerosol, and cloud Ecosystem satellite for launch, we’re gathering all the ingredients, um…instruments, and baking ourselves a fresh new satellite. Credit: NASA’s Goddard Space Flight Center/Scientific Visualization Studio. Video descriptions available. 

PACE will view the atmosphere and ocean surface from space. While highly useful for studying atmospheric aerosols, OCI is specifically designed to look for small aquatic organisms called phytoplankton that can be so numerous they influence the colors of the ocean. Phytoplankton play a large role in the ocean ecosystem — not only are they food sources for larger species, but they also convert carbon dioxide into organic matter through photosynthesis, playing an active role in moving carbon from the atmosphere into the ocean.

The PACE mission will help scientists learn more about the relationships between phytoplankton and the surrounding environment by measuring how light reflects off the ocean and through the atmosphere. Scientists can see these organisms in the ocean using satellites, but currently can’t differentiate the phytoplankton by type easily. Identifying types of phytoplankton help scientists to detangle some of the complex ecological systems in the oceans.

“When you look down at the ocean, you can see phytoplankton there and for the first time, with PACE, the scientists will be able to see what type of phytoplankton there are from space,” said Gary Davis, mission systems engineer at Goddard for the PACE mission. “Hopefully this mission will be able to communicate the importance of ocean health and the health of plankton to the whole world.”

To ensure the satellite is ready to gather this data, engineers put the satellite through, well, its paces. The thermal vacuum test that was just completed reduces atmospheric pressure as close to the vacuum of space as possible and then cycles through a wide range of temperatures. During the sunlit part of a spacecraft’s orbit, it can get very hot, up to approximately 50 degrees Celsius (122 degrees Fahrenheit); at other parts of the orbit, zero solar exposure means extremely low temperatures, as low as -90 degrees Celsius (-130 degrees Fahrenheit).

OCI, which was built at Goddard, can measure light in a multitude of colors, far more than previous satellites that share its frequent global coverage. Light variation by wavelength, the character of light by which it is defined, provides the color we see. OCI can detect a continuous spectrum of different wavelengths of light, and can even see colors beyond what the human eye can detect. By detecting more wavelengths, the instrument will allow scientists to tell the difference between types of phytoplankton from space. This is helpful in understanding the pathways of the carbon cycle in the atmosphere, land, and ocean, and characterizing the phytoplankton as harmful or helpful.

“OCI is really a stretch of the state of the art of what we can do right now,” said Davis. “It’s probably the most advanced thing we have on the observatory.”

Former ocean-observing satellites had the ability to measure light at a small set of wavelengths through the development of multi-spectral instruments. OCI has the ability to measure color continuosly at many ultraviolet, visible, and near infrared wavelengths, also known as hyperspectral imaging.

The previous missions can be imagined as a regular 8-color box of crayons, said Jeremy Werdell, project scientist for the PACE mission. Though still highly valuable for creating a complete picture, there are gaps in between the shades of colors. For PACE, OCI can be imagined as a 128-color box of crayons, filling in those gaps using smaller and continuous intervals of wavelengths.

“With all of the colors of the rainbow here, most of us don’t know what we’re going to discover, because we’ve never had that chance on global scales,” Werdell said. “It’s the only mission planned at NASA or elsewhere that provide global hyperspectral, full colors of the rainbow everywhere, everyday.”

When light from the sun reflects off the ocean, that light has already traveled from the sun, through the atmosphere – clouds and aerosols that compose Earth’s atmosphere – and water before it reaches the plankton in the ocean. The light then bounces off the plankton and travels back through the water and atmosphere again. The light that makes its way through all those stages can tell a story through color but still needs to be analyzed and accounted for any atmospheric effects, which is where the polarimeters on PACE come into play.

The Hyper-Angular Rainbow Polarimeter 2 (HARP2) also recently completed TVAC testing, earlier in September. The instrument is one of two multi-angle polarimeters on PACE, which act as polarized sunglasses for the spacecraft, measuring how light bends as it travels through the water droplets, clouds, and aerosols in Earth’s atmosphere, informing scientists more about their physical properties, as well as providing another source of color measurements. HARP2 was built at the University of Maryland, Baltimore County.

SPEXone, the other multi-angle polarimeter, was built in the Netherlands by engineers from SRON Netherlands Institute for Space Research, Airbus Netherlands and NASA. Each of the three instruments will be integrated into the spacecraft as they complete their individual tests – and in fact, OCI was just lifted onto the spacecraft on November 21.

“We have an observatory!” said Werdell.

As the timeline of events for PACE ticks on, the days are being counted down, all leading to the launch scheduled for early 2024.

For more information on PACE, visit https://pace.gsfc.nasa.gov.

By Erica McNamee, Science Writer at NASA’s Goddard Space Flight Center