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In this 1988 photo, JPL Director Dr. Lew Allen (left) and his Deputy Director Dr. Peter Lyman

Dr. Peter T. Lyman in January 1990

Deputy Director Dr. Peter T. Lyman in his 9th floor office in August 1989

This month we remember Dr. Peter T. Lyman, who passed away in May 2020, with a series of photos from his tenure as Deputy Director of NASA’s Jet Propulsion Laboratory.

Dr. Lyman joined JPL in 1963, after serving in the Merchant Marine and Military Sea Transport Service. He earned three degrees, including a master's in naval architecture and a doctorate in mechanical engineering from the University of California at Berkeley. He worked on several different Mars missions at the beginning of his career, then became a manager with increasing responsibility in spacecraft design, information systems, mission management, and the Deep Space Network. Dr. Lyman became Deputy Director in 1987 and served in that position until he retired in 1992. He passed away on May 6, 2020 at the age of 90.

Explore the archives at https://jpl-nasa.libguides.com/archives.

TAGS: PETER LYMAN, DEPUTY DIRECTOR, JPL

  • Julie Cooper
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Dr. Henry Richter

In 2018 JPL celebrates the 60th anniversary of America’s first satellite, Explorer 1.

Henry Richter started working at JPL in 1955 as an engineer and Supervisor for the New Circuit Elements Group. Later he was a Staff Engineer for the Deep Space Network and then Chief of the Space Instruments Section (322). During the Explorer Project Dr. Richter was project manager for the satellite design, in charge of JPL experiments for the International Geophysical Year, and was liaison between the Satellite Instrumentation Group and the Operations and Data Groups. He published a book in 2015 –America’s Leap into Space: My Time at JPL and the First Explorer Satellites.

On Wednesday, January 31 at 3:30, Dr. Richter will present his JPL Story in the Hub (111-104), followed at 4:30 by a book signing. He’ll share the story of JPL’s role working for the Army/Caltech and of the remarkable people who were part of the Explorer team. During the late 1950s, JPL extended rocket engineering to spacecraft design, using components that were on the cutting edge of technology. When they were finally given the chance to combine the instruments, upper stages, and launch vehicle, they accomplished the task in just a few months.

The JPL documentary Explorer 1 and the 1958 film X Minus 80 Days will be shown in the 111 Hub on Tuesday, January 30 from 12:00-1:15.

Explore the archives at https://jpl-nasa.libguides.com/archives.

TAGS: HENRY RICHTER, DEEP SPACE NETWORK, JPL

  • Julie Cooper
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Icebergs dot the seascape in Baffin Bay,

Baffin Island, specifically, the largest island in Canada.

“What are we doing all the way out here?” I thought. If I looked out the left side of NASA’s modified G-III aircraft, I could see Canada out the window—Baffin Island, specifically, the largest island in Canada, part of its northeast territory. And if I looked out the right side, I could see the west coast of Greenland. We were pretty much halfway between the two, right in the middle of Baffin Bay, and I was surprised.

Baffin Bay in Eyes on the Earth
Baffin Bay as it appears in NASA's Eyes on the Earth interactive.
I was surprised that it was even possible to see Canada from Greenland. Most maps are so distorted in the high latitudes that both distance and perspective are off, and I hadn’t realized that the two islands were as close as they are to each other – just about 200 miles apart in some places. I also didn’t realize that Oceans Melting Greenland had planned to gather ocean temperature and salinity profiles so far offshore from Greenland’s coastline.

At a glacial pace

I went over to where Flight Engineer Terry Lee kept the map of all the scheduled drop positions and stared at it for a while. She’d marked with a green highlighter the places where she’d already released science probes through a tube in the bottom of the plane. (Hahahah, yes! There’s a hole in the plane through which Aircraft eXpendable Conductivity Temperature Depth (AXCTD) probes leave the aircraft to travel 5,000 feet down to the sea surface and then another 1,000 meters into the ocean, sending back data as they go.)

Baffin Bay map with highlighted drop sites
Lee's map of the scheduled drop sites.
And even though I’d seen this map before, the yellow dots representing scheduled probe drops were right in front of me, out in the middle of the sea, about 100 miles off the coastline. And that confused me because I presumed that this location, this far out at sea, wouldn’t have a layer of fresh water at the sea surface. I figured this far out we’d find salty 3- to 4-degree North Atlantic Ocean Water at the sea surface. So why weren’t we closer to shore where the land ice was melting?

I looked out the window as we flew on. Icebergs dotted the seascape. Each one had once been part of a vast ice sheet that’s been around for hundreds of thousands of years. Each one had moved – at a glacial pace, mind you – from the interior, down through one of the many fjords that slice through the Greenland coastline, and finally out to sea, where they would ultimately melt away. The ‘bergs were large, and it was fun to fly over them and look at their perfect whiteness against the stunning blue sea. All of us would gather on one side of the plane as we passed over a ‘berg, and then quickly jump to the other side to look for it again as we passed by it. But even though there were hundreds of icebergs floating around out there, Baffin Bay is vast — more than 250 thousand square miles. So, in the grand scheme of things, the icebergs seemed inconsequential, incapable of affecting the ocean salinity more than a small amount.

Real-time data

Project Manager Steve Dinardo
Project Manager Steve Dinardo tracks the real-time data coming from the ocean probes.
I was in the midst of pondering all this, not wanting to bother any of the busy team members, when Oceans Melting Greenland Project Manager Steve Dinardo called me over to the bank of computer monitors where he was working. He motioned for me to trade headsets. After I gave him mine and I put on his, I could hear the AXCTD probe sending its signal to the plane as it descended through the water column, and the noise reminded me of the sound a Wookiee from Star Wars makes.

As I was listening, I could see temperature and salinity values arriving in real-time on the monitor. “Wow, no way!” I exclaimed. “That’s insane.” All the way in the middle of Baffin Bay, 100 miles offshore, the ocean was fresher on the surface. I watched the salinity values increase as the probe sank. The temperature profile also reflected a scenario of near-zero-degree water at the surface with 3- to 4-degree ocean water below. That upper layer is Arctic Ocean Water, which is way less salty than the warmer North Atlantic Ocean Water that lies beneath it.

An iceberg
One of the many icebergs we flew by.
And this is the whole point of NASA’s Oceans Melting Greenland mission—to find out how far that warmer North Atlantic Ocean Water has penetrated. Knowing this will help us measure the quantity and rate at which the warmer North Atlantic Ocean Water is melting the Greenland Ice Sheet.

I walked back to look at the yellow dots on the map of the scheduled probe drops one more time. We were as far away from the coast as we would be; the rest of the drops were closer to shore. I wondered how the temperature and salinity profiles in the coastal waters would compare to those from the open ocean.

And the point of the mission flooded my mind again. I looked out the window, across the stretch of Baffin Bay at the Greenland coastline, where groups of icebergs dotted the horizon. In this vast expanse, no one’s done this before, no one knows what this ocean water is like, and we are about to find out.

Find out more about Oceans Melting Greenland.

View and download OMG animations and graphics.

Thank you for your comments.

Laura

TAGS: CLIMATE, OCEANS, MELTING, GREELAND, NASA, JET PROPULSION LABORATORY, JPL

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Earth with directions

Greenland is one of the few places that’s harder to get to than outer space

I’m going to Greenland. I told my brother, and he replied, “Oh cool, I’m headed to Ireland.” That’s the typical response, as if Greenland were just some place one could book a ticket to, with commercial airports, and hotels, and restaurants and stuff. But … no, Greenland is different. It’s actually not an independent country, for example. (It’s a territory of Denmark.)

The other response I keep getting is that dumb, corny comment about it not being green. So it seems like the only thing we collectively understand about Greenland is that it’s a place to go and it has a hypocritical name.

But that is just so wrong. My husband and I finally got on the same page this morning when he opened the Google Maps satellite view of Kangerlussauq Airport, where I’m scheduled to land. “Oh,” he said. “It’s a barren dirt strip in the middle of nowhere and nothing.”

At last, an acknowledgement of the truth. The only place that’s harder to get to than Greenland is outer space. I know that sounds funny, but I’m not even kidding. (Okay, okay, Antarctica is also hard to get to, along with the Marianas Trench. Ugh.)

I first became aware of how little we know about Greenland when I was creating NASA’s Global Ice Viewer for our climate website. I found shots from Alaskan glaciers that dated all the way back to the late 1800s for the gallery. Gents with top hats and ladies in bustles with Victorian cameras stood on the ice. But Greenland? Photos taken before the 1980s are extremely rare.

Muir Glacier, Alaska, disappears.
Muir Glacier, Alaska, disappears. Left image: 1891. Right image: 2005. Photographed by G.D. Hazard in 1891 and by Bruce F. Molnia in 2005. Courtesy of the Glacier Photograph Collection. Boulder, Colorado, US and the National Snow and Ice Data Center/World Data Center for Glaciology.

And while most people understand that increased atmospheric temperatures have been melting the ice sheet from above, global warming has also been increasing ocean temperatures. And this means the ocean waters surrounding Greenland are also melting the ice sheet from around its edges.

Which is the reason I’m headed up there with NASA’s Oceans Melting Greenland (OMG) campaign in the first place: to measure the temperature and salinity of those unknown waters. See, the fresh water that flows into the ocean from ice melt is about 0 degrees and less dense, so it floats right at the sea surface. The North Atlantic Ocean Water is about 3 or 4 degrees, salty and denser, so it sits right below the fresh melt water. And these two waters don’t really mix much. When the 3- or 4-degree North Atlantic Ocean Water gets in contact with Greenland’s ice sheet, it’s warm enough to melt it.

But no one knows the melt rate yet. No one.

Even though Greenland’s melting ice sheet impacts each and every one of us right now. The rate of ice melt will determine how much sea level rise we’re going to get, 5 feet or 10 feet or 20, everywhere, all over planet Earth, not just in Greenland, but at coastlines near you and me.

This is where that whole NASA “exploring the unknown” theme comes in. Next week, the OMG team (including yours truly) will be in Greenland on NASA’s G-III aircraft. We’ll spend five weeks flying around the entire coastline, measuring the salinity and temperature of the coastal waters by dropping 250 Aircraft eXpendable Conductivity Temperature Depth (AXCTD) science probes through a hole in the bottom of the plane. The reason we’re going in September is that’s the warmest time of the year in the ocean, the ice will reach its lowest extent and we’ll be able to measure as much of the coast as possible. The plan is to repeat the same mission for five years to find out what the melt rate is and how much that rate is increasing.

Am I excited? Yes, beyond. Aside from the science preparation, it took months and months of personal prep. I passed a Federal Aviation Administration medical exam, then got trained in First Aid, CPR, AED, hypoxia, disorientation, survival, and hearing conservation, and then had to buy steel-toed shoes, which are required to fly on that NASA plane. Today, I am psyched beyond belief.

Underwater disorientation training in action.

Why else would anyone work so hard to do something? Just like the rest of the team, I hope our work really makes a difference.

TAGS: GREENLAND, EARTH, NASA, JPL, JET PROPULSION LABORATORY, GLOBAL WARMING, OCEANS

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