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NASA’s JPL Lays Off Another 325 People
NASA’s Jet Propulsion Lab has announced a second round of layoffs for 2024, this time laying off 325 people – about 5% of its workforce. The announcement was made on Nov. 12 in a memo sent to employees, which notes the layoffs could have been even larger. The last cut was made this past February, when 530 employees were let go. Part of the issues which forced the layoffs comes from the the possible cancelation of the Mars Sample Return mission. With the October 2024 launch of Europa Clipper, JPL doesn’t have a flagship mission in the pipeline right now.
As with the layoffs in February, the cuts have nothing to do with the individual performance; it’s all budget-related and an attempt to balance the books. NASA Headquarters passed on funding constraints in the current budget to JPL, and while JPL has tried to manage them, the results are the two rounds of difficult layoffs.
“This is a message I had hoped not to have to write,” JPL Director Laurie Leshin said in the memo sent to all staff members. “Despite this being incredibly difficult for our community, this number [of layoffs] is lower than projected a few months ago thanks in part to the hard work of so many people across JPL.”
Dr. Laurie Leshin has been the director of the Jet Propulsion Laboratory since May 2022. Credit: JPL.Leshin said the lab’s leadership has had to deal with “continued funding challenges” and an uncertain future as NASA has been juggling and reconsidering its priorities for deep space exploration. She noted that the reduction was spread across nearly all areas of JPL, including technical, project, business, and support areas to meet the available funding for Fiscal Year 2025. Leshin said that the outcome of the presidential election last week did not have any bearing on the layoffs.
“We have taken seriously the need to re-size our workforce, whether direct-funded (project) or funded on overhead (burden). With lower budgets and based on the forecasted work ahead, we had to tighten our belts across the board, and you will see that reflected in the layoff impacts,” Leshin wrote.
All employees were told to work from home today (Nov. 13) and everyone would receive an email whether their position was being eliminated or not. Leshin said JPL would offer “personalized support to our laid-off colleagues who are part of the workforce reduction, including offering dedicated time to discuss their benefits, and several other forms of assistance.”
Artist’s concept of a Europa Clipper mission. Credit: NASA/JPLThis second round of layoffs were not a surprise. During a recent town hall with employees, Leshin discussed the continued funding challenges and projections of what the potential impact on the JPL workforce could look like. She indicated her team had been working through multiple workforce scenarios to address the changes in funding, with the goal of minimizing adverse effects on JPL’s capabilities and workers. But despite their efforts, the conclusion was that this additional workforce reduction was inevitable.
After the layoffs today, JPL will be left with about 5,500 regular employees.
“These are painful but necessary adjustments that will enable us to adhere to our budget while continuing our important work for NASA and our nation,” JPL said in a statement.
On social media, JPL employees called the news “devastating,” and “awful.” Another said, “Can’t imagine the stress this will produce.”
But Leshin also said she believed this would be the last workforce reduction needed for the foreseeable future and that staffing levels at this point are now “stable and supportable.”
“While we can never be 100 percent certain of the future budget, we will be well positioned for the work ahead,” Leshin wrote. “This may not help much in this difficult moment, but I do want to be crystal clear with my thoughts and perspective. If we hold strong together, we will come through this, just as we have done during other turbulent times in JPL’s nearly 90-year history.”
Dare Mighty Things The “Dare Mighty Things” sign at JPL. Image by Nancy Atkinson.JPL has a long and storied history — “Dare Mighty Things” is the Lab’s motto — with the Lab’s origins dating back to the 1930s, when Caltech professor Theodore von Kármán oversaw pioneering work in rocket propulsion. In the 1960s, JPL began to develop robotic spacecraft to explore other worlds, beginning with the Ranger and Surveyor missions to the Moon, quickly followed by Mariner missions to Mercury, Venus and Mars. Now, missions and instruments built or managed by JPL have visited every planet in our Solar System as well as studying the Sun. The iconic Voyager missions have now entered interstellar space.
Despite the difficult layoffs, Leshin was hopeful for what’s to come for JPL.
“We are an incredibly strong organization—our dazzling history, current achievements, and relentless commitment to exploration and discovery position us well for the future,” she wrote.
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Lessons From Ancient Earth’s Atmosphere: From Hostile to Hospitable
Will we ever understand how life got started on Earth? We’ve learned much about Earth’s long, multi-billion-year history, but a detailed understanding of how the planet’s atmospheric chemistry evolved still eludes us. At one time, Earth was atmospherically hostile, and its transition from that state to a planet teeming with life followed a complex path.
What made Earth so special? Research shows that while Earth is completely different from its neighbouring planets now, in the past, it shared many atmospheric characteristics with modern-day Venus and Mars. How did Earth turn out so different?
A better understanding of Earth’s atmospheric journey can help us understand some of the distant exoplanets we’ve detected. In the near future, new telescopes will be revealing more details of exoplanet atmospheres. Many puzzles await, and some of the solutions to understanding them could be found on ancient Earth.
Ancient Earth had a reducing atmosphere, which means that there was a lack of free oxygen. The atmosphere contained reducing gases like hydrogen and methane. These gases quickly react with oxygen and remove it from the atmosphere. Some of those same molecules also react with UV light, and the chemical reactions produce organic molecules.
While that’s a general outline of some aspects of ancient Earth’s atmosphere, there’s a lot of detail that needs to be constrained before a clearer picture emerges of Earth’s transformation.
Researchers at Tohoku University, the University of Tokyo, and Hokkaido University have developed a new model of atmospheric chemical reactions that sheds light on how Earth’s atmosphere evolved and how the first life may have arisen.
The research is “Self-Shielding Enhanced Organics Synthesis in an Early Reduced Earth’s Atmosphere.” It’s published in the journal Astrobiology, and Tatsuya Yoshida from Tohoku University is the lead author.
Before life could appear, Earth needed a good supply of important prebiotic molecules like formaldehyde (H2CO) and poisonous hydrogen cyanide (HCN). These molecules are critical because they can undergo a wide variety of reactions to produce the more complex molecules life requires. They produce amino acids, sugars, and nucleobases, which are the building blocks for DNA and RNA.
Research shows that a highly reduced atmosphere like ancient Earth’s is a candidate for producing these important prebiotic molecules, especially if it’s above a primordial ocean. Earth’s primordial ocean, or proto-ocean, was also much different from the modern ocean. Among other things, it was acidic because of volcanic gases. It was also hot.
Ancient Earth had hot, acidic oceans and a reducing atmosphere that lacked free oxygen. Image Credit: NASA/T.Pyle“Ancient Earth was nothing like our current home,” explains co-author Shungo Koyama, also from Tohoku University. “It was a much more hostile place; rich in metallic iron with an atmosphere containing hydrogen and methane.”
The Sun’s UV radiation bombarded ancient Earth unimpeded by an ozone layer, driving chemical reactions in the ancient Earth’s atmosphere, oceans, and crust.
That much is understood. But what scientists desire is a better understanding of all of the details. “However, the branching ratio between organic matter formation and oxidation remains unknown despite its significance on the abiotic chemical evolution of early Earth,” the authors explain.
The researchers developed a photochemical model for a reduced Earth’s atmosphere primarily containing H2 and CH4. Their model is based on one that’s been successfully applied to Jupiter’s atmosphere, the atmospheres of ancient and modern Mars, and runaway greenhouse atmospheres. The model considers 342 separate chemical reactions and also includes atmospheric hydrogen escape and atmospheric mixing.
The young Sun emitted more intense UV radiation than the modern Sun. The UV broke water molecules down into hydrogen and oxygen radicals. Radicals have one unpaired electron, which makes them chemically reactive. Much of the hydrogen escaped to space, while the oxygen did not.
Illustration of what the Sun may have been like 4 billion years ago. Scientists think that overall, the young Sun was fainter than it is now. But it was also more active and had a higher level of magnetic activity. That activity made the Sun emit more UV than it does now. Credit: NASA’s Goddard Space Flight Center/Conceptual Image LabThe oxygen radicals combined with methane led to the creation of organic molecules like HCN and H2CO.
Hydrocarbons, such as acetylene (C2H2) and methylacetylene (C3H4), were also present in the atmosphere. These chemicals absorbed some UV, shielding the lower atmosphere from photodissociation. “According to our results, UV absorptions by gaseous hydrocarbons such as C2H2 and C3H4 significantly suppress the H2O photolysis and following CH4 oxidation,” the authors explain. The atmospheric methane helped drive the production of organics.
That allowed organic molecules to accumulate into a prebiotic soup, which could’ve provided the building blocks for life.
“Accordingly, nearly half of initial CH4 possibly becomes converted to heavier organics along with deposition of prebiotically essential molecules such as HCN and H2CO on the surface of a primordial ocean for a geological timescale order of 10-100 Myr,” the authors write.
This diagram shows the evolution of Earth’s ancient atmosphere estimated by this study. Earth initially had a reducing atmosphere with lots of H2 and some CH4. Intense UV energy from the Sun split water into hydrogen and oxygen radicals, with much of the hydrogen escaping into space. CH4 that remains in the atmosphere is converted into organics. Earth loses its ancient CH4 and H2-rich atmosphere, the CH4 decomposes, and a layer of organics several hundred meters thick accumulates. Image Credit: Yoshida et al. 2024As time went on and the reduced atmosphere evolved, H2CO and HCN were continuously synthesized and accumulated in the ocean. H2CO and HCN are considered to be critical in prebiotic chemistry. According to these results, Earth’s early atmosphere was a major source of these important prebiotic molecules. They didn’t need to come from meteorites or comets.
The authors calculate that a layer of organic several hundred meters thick may have covered the ocean. “The continuous supply of these prebiotically important molecules could potentially lead to the synthesis of amino acids, nucleobases, sugars, and their polymers,” the researchers write.
“There may have been an accumulation of organics that created what was like an enriched soup of important building blocks. That could have been the source from which living things first emerged on Earth,” said lead author Yoshida.
The model shows that Earth’s early atmosphere was eerily similar to modern-day Mars and Venus. However, Earth evolved into a completely different world. How?
This research doesn’t explain it all. But it does deepen our understanding of the evolutionary track Earth followed.
The question becomes, is Earth unique? Or is it a common path that exoplanets in other Solar Systems can follow?
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