Titan

nasa-awards-spacex-a-contract-for-one-of-the-few-things-it-hasn’t-done-yet

NASA awards SpaceX a contract for one of the few things it hasn’t done yet

Notably, the Dragonfly launch was one of the first times United Launch Alliance has been eligible to bid its new Vulcan rocket for a NASA launch contract. NASA officials gave the green light for the Vulcan rocket to compete head-to-head with SpaceX’s Falcon 9 and Falcon Heavy after ULA’s new launcher had a successful debut launch earlier this year. With this competition, SpaceX came out on top.

A half-life of 88 years

NASA’s policy for new space missions is to use solar power whenever possible. For example, Europa Clipper was originally supposed to use a nuclear power generator, but engineers devised a way for the spacecraft to use expansive solar panels to capture enough sunlight to produce electricity, even at Jupiter’s vast distance from the Sun.

But there are some missions where this isn’t feasible. One of these is Dragonfly, which will soar through the soupy nitrogen-methane atmosphere of Titan. Saturn’s largest moon is shrouded in cloud cover, and Titan is nearly 10 times farther from the Sun than Earth, so its surface is comparatively dim.

The Dragonfly mission, seen here in an artist’s concept, is slated to launch no earlier than 2027 on a mission to explore Saturn’s moon Titan. Credit: NASA/JHUAPL/Steve Gribben

Dragonfly will launch with about 10.6 pounds (4.8 kilograms) of plutonium-238 to fuel its power generator. Plutonium-238 has a half-life of 88 years. With no moving parts, RTGs have proven quite reliable, powering spacecraft for many decades. NASA’s twin Voyager probes are approaching 50 years since launch.

The Dragonfly rotorcraft will launch cocooned inside a transit module and entry capsule, then descend under parachute through Titan’s atmosphere, which is four times denser than Earth’s. Finally, Dragonfly will detach from its descent module and activate its eight rotors to reach a safe landing.

Once on Titan, Dragonfly is designed to hop from place to place on numerous flights, exploring environments rich in organic molecules, the building blocks of life. This is one of NASA’s most exciting, and daring, robotic missions of all time.

After launching from NASA’s Kennedy Space Center in Florida in July 2028, it will take Dragonfly about six years to reach Titan. When NASA selected the Dragonfly mission to begin development in 2019, the agency hoped to launch the mission in 2026. NASA later directed Dragonfly managers to target a launch in 2027, and then 2028, requiring the mission to change from a medium-lift to a heavy-lift rocket.

Dragonfly has also faced rising costs NASA blames on the COVID-19 pandemic and supply chain issues and an in-depth redesign since the mission’s selection in 2019. Collectively, these issues caused Dragonfly’s total budget to grow to $3.35 billion, more than double its initial projected cost.

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Infamous $30 Logitech F710 called out in $50M lawsuit over Titan sub implosion

what could go wrong? —

Family of dead Titanic expert blasts “hip” electronics.

Stockton Rush shows David Pogue the game controller that pilots the OceanGate Titan sub during a CBS Sunday Morning segment broadcast in November 2022.

Enlarge / OceanGate CEO Stockton Rush shows David Pogue the 2010-era game controller that pilots the Titan sub during a CBS Sunday Morning segment broadcast in November 2022.

CBS Sunday Morning

In a 2022 CBS Sunday Morning segment, CEO Stockton Rush of deep-water submersible company OceanGate gave journalist David Pogue a fun reveal. “We run the whole thing with this game controller,” Rush said, holding up a Logitech F710 controller with 3D-printed thumbstick extensions. The controller was wireless, and it was the primary method for controlling the Titan submersible, which would soon make a visit to the wreck of the Titanic. Pogue laughed. “Come on!” he said, covering his eyes with his hand.

Journalists loved the controller story, covering the inexpensive F710 and the ways that video game controllers have become common control solutions in various military and spaceflight applications in recent years. After all, if your engineers and pilots grew up using two-stick controllers to waste their friends in Halo multiplayer, why not use that built-in muscle memory for other purposes?

So the use of a video game controller was not in itself a crazy decision. But after the Titan sub imploded on a June 2023 dive to the Titanic site, killing all five passengers including Stockton Rush, the use of a wireless $30 control interface began to look less “cool!” and more “isn’t that kind of risky?” The only question at that point was how long it would take the Logitech F710 to show up in a lawsuit.

This week, we got our answer. In the first Titan wrongful death lawsuit, filed this week by the estate of Paul-Henri Louis Emile Nargeolet, the Logitech controller comes in for some prominent criticism.

“Hip, contemporary, wireless”

Nargeolet “was known worldwide as ‘Mr. Titanic,'” says the new lawsuit (PDF) against OceanGate, Rush’s estate, and various companies that helped build the Titan. Nargeolet had been on 37 dives to the Titanic wreckage and, on his final dive, was working with OceanGate as a Titan crewmember who would “guide other crewmembers and assist with navigation through the Titanic wreckage, which he knew so well.”

The lawsuit reiterates all the main criticisms of the Titan.

First, the sub was not made from titanium (as most submersibles are), which gets stronger under compression; it was made instead from carbon fiber, which can crack under repeated compression. Rush, who saw himself as an innovator like “Steve Jobs or Elon Musk,” the complaint says, once told Pogue, “At some point, safety just is pure waste.” Rush thought he had found a lighter way to build subs.

Second, the complaint singles out the Titan’s “hip, contemporary, wireless electronics systems.” (Those adjectives are not compliments).

TITAN was piloted using a mass-produced Logitech video game controller (normally used with a PlayStation or Xbox) rather than a controller custom-made for TITAN’s design and operation. Moreover, the controller worked via Bluetooth, rather than being hardwired. TITAN also had only “one button” (for power) within its main chamber—the remainder of its controls (for lights, ballast and so on) and gauges (for depth, oxygen level and so forth) were touchscreen. RUSH stated that TITAN was “to other submersibles what the iPhone was to the BlackBerry.” As with an iPhone, however, none of the controller, controls or gauges would work without a constant source of power and a wireless signal.

OceanGate’s previous submersible, the Cyclops I, had also used a video game controller (a Sony DualShock 3) and some other wireless tech.

The DualShock 3 controller used to run the Cyclops I.

Enlarge / The DualShock 3 controller used to run the Cyclops I.

The complaint quotes an expert saying that such systems provided “multiple points of failure” and that “‘every sub in the world has hardwired controls for a reason,’ namely that a loss of signal would not imperil the vessel.” But such issues were “disregarded by OceanGate, as Titan employed nearly identical systems to Cyclops I,” says the complaint.

The lawsuit also attacks the engineering team that designed and integrated all the electronics systems into Titan, saying that the team was made up mostly of current or recent Washington State University grads with “virtually no real-world experience and no prior exposure to the deep-sea diving industry.”

The complaint does not allege that the Logitech wireless controller, the carbon fiber construction, Titan’s innovative porthole, or the use of disparate materials with differing expansion/compression coefficients—four main areas of criticism—were individually responsible for the sub’s implosion. But it does suggest that these systems could have together contributed to a “daisy chain of failures of multiple improperly designed or constructed parts or systems.” The complaint says that Nargeolet’s estate is entitled to at least $50 million in damages.

Too good to be true

A final investigatory report from various government agencies has been in process for over a year and has not yet been completed, but it seems likely that the Logitech controller—along with the five people on the sub—is gone forever.

But the prospect of a cheap piece of plastic surviving the catastrophic implosion was just too good for social media to ignore. Shortly after the Titan disaster, people began “sharing a photo that purports to show the controller resting on the bottom of the sea,” according to a 2023 AP fact check. “The image shows a sandy ocean bottom with a part of the photo magnified to supposedly show a close up of the controller.”

“The cheapest part survived,” one X (Twitter) user posted.

Alas, it did not; the photo was a fake.

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Saturn’s moon Titan has shorelines that appear to be shaped by waves

Surf the moon —

The liquid hydrocarbon waves would likely reach a height of a meter.

Ligeia Mare, the second-largest body of liquid hydrocarbons on Titan.

Enlarge / Ligeia Mare, the second-largest body of liquid hydrocarbons on Titan.

During its T85 Titan flyby on July 24, 2012, the Cassini spacecraft registered an unexpectedly bright reflection on the surface of the lake Kivu Lacus. Its Visual and Infrared Mapping Spectrometer (VIMS) data was interpreted as a roughness on the methane-ethane lake, which could have been a sign of mudflats, surfacing bubbles, or waves.

“Our landscape evolution models show that the shorelines on Titan are most consistent with Earth lakes that have been eroded by waves,” says Rose Palermo, a coastal geomorphologist at St. Petersburg Coastal and Marine Science Center, who led the study investigating signatures of wave erosion on Titan. The evidence of waves is still inconclusive, but future crewed missions to Titan should probably pack some surfboards just in case.

Troubled seas

While waves have been considered the most plausible explanation for reflections visible in Cassini’s VIMS imagery for quite some time, other studies aimed to confirm their presence found no wave activity at all. “Other observations show that the liquid surfaces have been very still in the past, very flat,” Palermo says. “A possible explanation for this is at the time we were observing Titan, the winds were pretty low, so there weren’t many waves at that time. To confirm waves, we would need to have better resolution data,” she adds.

The problem is that this higher-resolution data isn’t coming our way anytime soon. Dragonfly, the next mission to Titan, isn’t supposed to arrive until 2034, even if everything goes as planned.

To get a better idea about possible waves on Titan a bit sooner, Palermo’s team went for inferring their presence from indirect cues. The researchers assumed shorelines on Titan could have been shaped by one of three candidate scenarios. They first assumed there was no erosion at all; the second modeled uniform erosion caused by the dissolution of the bedrock by the ethane-methane liquid; and the third assumed erosion by wave activity. “We took a random topography with rivers, filled up the basin-flooding river valleys all around the lake. Then, we then used landscape evolution computer model to erode the coast to 50 percent of its original size,” Palermo explains.

Sizing the waves

Palermo’s simulations showed that wave erosion resulted in coastline shapes closely matching those actually observed on Titan.

The team validated its model using data from closer to home. “We compared using the same statistical analysis to lakes on Earth, where we know what the erosion processes are. With certainty greater than 77.5 percent, we were able to predict those known processes with our modeling,” Palermo says.

But even the study that claimed there were waves visible in the Cassini’s VIMS imagery concluded they were roughly 2 centimeters high at best. So even if there are waves on Titan, the question is how high and strong are they?

According to Palermo, wave-generation mechanisms on Titan should work just like they do on Earth, with some notable differences. “There is a difference in viscosity between water on Earth and methane-ethane liquid on Titan compared to the atmosphere,” says Palermo. The gravity is also a lot weaker, standing at only one-seventh of the gravity on Earth. “The gravity, along with the differences in material properties, contributes to the waves being taller and steeper than those on Earth for the same wind speed,” says Palermo.

But even with those boosts to size and strength, could waves on Titan actually be any good for surfing?

Surf’s up

“There are definitely a lot of open questions our work leads to. What is the direction of the dominant waves? Knowing that can tell us about the winds and, therefore, about the climate on Titan. How large do the waves get? In the future, maybe we could tell that with modeling how much erosion occurs in one part of the lake versus another in estimated timescales. There is a lot more we could learn,” Palermo says. As far as surfing is concerned, she said that, assuming a minimum height for a surfable wave of around 15 centimeters, surfing on Titan should most likely be doable.

The key limit on the size and strength of any waves on Titan is that most of its seas are roughly the size of the Great Lakes in the US. The largest of them, the Kraken Mare, is roughly as large as the Caspian Sea on Earth. There is no such thing as a global ocean on Titan, and this means the fetch, the distance over which the wind can blow and grow the waves, is limited to tens of kilometers instead of over 1,500 kilometers on Earth. “Still, some models show that the waves on Titan be as high as one meter. I’d say that’s a surfable wave,” Palermo concluded.

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