In early 1989, a series of thermal tests were conducted on the Microwave Limb Sounder (MLS) Instrument, which was part of the Upper Atmosphere Research Satellite (UARS).
The MLS System Thermal Vacuum (STV) test program was designed to evaluate its thermal integrity and functions in a simulated space environment. It included a 24-hour bakeout, six phases of thermal balance tests, and a thermal cycling test of the instrument in flight configuration, using a variety of heaters and lamps.
This photo shows the Ten-Foot Space Simulator located in Building 248, with a quartz lamp array approximately seven feet tall. This array faced the primary reflector during testing and helped to heat the chamber to 80°C (176°F). The vacuum chamber shroud was lowered over the test fixture, and the chamber walls and floor were maintained at -100°C to -179°C during testing.
For more information about the history of JPL, contact the JPL Archives for assistance.
In January 1953, JPL was in the market for its first digital computer.
After investigating the possibilities, a site visit was made to Consolidated Engineering Corporation (CEC) in Pasadena and the CEC Model 30-203 digital computer, shown in this photo, was eventually selected. The prototype at CEC was given the project number 36-101. JPL and the National Bureau of Standards were the first two customers to order the computer – the one ordered by JPL was 36-102, and the one for NBS was 36-103.
JPL's computer was finally delivered and operational in July 1954. It cost approximately $135,000 (more than $1 million in 2016 dollars). That did not include the operator's console, paper tape input and output, punch card unit, or other related equipment. It featured magnetic drum storage of about 4000 words (a "word" being a number or command) and a word length of 10 decimal digits. It contained more than 1,500 vacuum tubes.
For more information about the history of JPL, contact the JPL Archives for assistance. [Archival and other sources: Section 371 photo albums, Combined Bimonthly Summary No. 33, Datatron Chronology.)
Sigh. Sometimes life feels heavy.
Even as the holidays approach and we’re all supposed to be in a holiday spirit, supposed to be joyous. Sometimes we’re just not there.
But, as always, NASA gives me the opportunity to look at Earth from the highest perspective. From above, the world appears remote and untouched. There’s nothing but the timeless, immaculate and infinite beauty of our planet.
Together, you and I get to take this opportunity to share thankfulness for our Earth and everything pristine and beautiful about it.
Thank you for reading. I really mean it.
Slow down and relax. Earth is beautiful.
Earth, from the vantage point of space: Serene, breathtaking, magnificent. No matter how crazy busy your day is, no matter the level of stress, or chaos, or distraction, take a moment today—right now, in fact—to step back and feast on the great wonder of our home planet, Earth.
On October 31, 1968 JPL celebrated the 32nd anniversary of the first rocket motor tests in the Arroyo Seco.
Swoosh! It’s not a sound so much as a feeling.
You feel it in your ears and through your whole body. And everyone on the plane — two NASA G-III pilots, two flight engineers and the rest of the Oceans Melting Greenland (OMG) crew—feels it at exactly the same time. It has become our inside joke.
The swoosh happens every time the flight engineers drop an Aircraft eXpendable Conductivity Temperature Depth (AXCTD) probe through a hole in the bottom of the plane. The AXCTD comes in a 3-foot-long gray metal tube—with a parachute. After it hits the water, the probe measures ocean temperature and salinity from the sea surface down to about 1,000 meters. The tiny difference between cabin and outside pressure pushes the probe out and makes ears pop at the same time.
This is the second week of our three- to four-week mission that will be repeated every September/October for the next five years. We’re finally starting to iron out all the minor details in our protocol. With so many moving parts, the protocol is important, and the intricate timing helps us make sure no one forgets any details and we get the most accurate record of when and where we drop each one.
- 1. Project Manager Steve Dinardo announces “Data recorder ready.”
- 2. Pilots Bill Ehrenstrom and Scott Reagan call out the cloud and ice conditions and the number of minutes to the drop site. Then they determine the altitude for the approach.
- 4. At 50 seconds from the drop site, the plane slows down and cruises at about 5,000 feet.
- 5. At 20 seconds, Lee and Vaughn open the cap of the tube—you know, the one with that hole through the bottom of the plane—and everyone’s ears pop (the first time). Protocol states that they announce “Tube open!” but since our ears just popped, we often hear “Well, of course the tube’s open” or “As you already know—tube’s open.”
- 6. At 10 seconds, the pilots count down to 1 and say “drop.” The engineers reply “Sonde’s away” and we all feel that swoosh. There it is. Our ears pop for the second time as the AXCTD is “swooshed” down the tube and out through the hole in the bottom of the plane. (And yes, we all still look at each other with our sly smiles because it’s so much fun to say, “hole in the bottom of the plane.”)
- 7. It is the swoosh, more than anything said during the lengthy protocol script playing through my headset, that tells me—OMG lead scientist Josh Willis—to mark the drop on my GARMIN, a GPS we use to record the location of each drop.
- 8. After each drop, our aircraft banks steeply and we all silently celebrate the fact that we don’t get motion sickness. We continue circling during the six or so minutes it takes for the science probe to parachute down 5,000 feet to the sea surface and make its way through the water column, sending back data to us in real-time on the plane.
During our many, often challenging hours on the plane together, we share these little inside jokes and laugh—not caring if anyone in the outside world thinks it’s funny. Seems like we are bonding. I couldn’t be happier.
I went off for a day to visit Russell Glacier, which flows from the Greenland Ice Sheet down the Akuliarusiarsuup Kuua River, into the Kangerlussuaq Fjord and out into the Davis Strait. I knew I'd watch it melt right in front of me. And I expected to feel sad standing there so close to such an obvious and intense signal of global warming and climate change.
I stood there as the Arctic sun moved onto the horizon behind me, breathing the cool air, listening to the loud rush of meltwater passing between me and the 200-foot wall of ice in front of me. I thought about the 100,000-year span of time that this ice sheet has lasted on this planet. I looked toward the Akuliarusiarsuup Kuua River valley thinking about the future of that meltwater as it flowed out to sea. As we continue adding heat-trapping gases to our environment, our climate will keep changing and this meltwater will only increase. Someday the whole ice sheet may be gone.
I was supposed to feel sad. But I didn't. Instead I just felt grateful to be alive, right here, right now, in 2016. To be alive in that time between 100,000 years ago and the whatever-will-happen-in-our-climate-changed future.
I hope you understand.
TAGS: WALL ICE TRANSITION
JPL photographers don’t take only technical photos, although you’ll find plenty of images of parts, testing, construction, and spacecraft assembly in the JPL Archives photo collection.
On occasion, photographers explore the surrounding area, and take more artistic photos suitable for publicity, brochures, or for display in a JPL building. The newest Historical Photo of the Month shows one example – an early deep space communications antenna in California’s Mojave Desert.
This photo shows the “Transmitting Station” at what was then called the Goldstone Deep Space Instrumentation Facility (also known as the Goldstone Tracking Station or GTS). The 10-kw radio transmitter and 85-foot antenna were installed about two years after the first station ( the “Receiving Station”) became operational in December 1958. It added voice communication and radio command capabilities to the expanding Goldstone operation.
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.
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.)
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.
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.
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.
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.
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.
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.