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NASA’s Webb Telescope mirror crushes “most optimistic predictions” after final alignment

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4 years ago

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NASA says that the nascent James Webb Space Telescope’s (JWST) “optical performance…continues to be better than the…most optimistic predictions” after completing the alignment of its record-breaking mirror.

Between 7 and 14 years behind schedule and over budget by a factor of 2 to 10, an Arianespace Ariane 5 rocket sent the Webb Telescope on its way to deep space on December 25th, 2021. Weighing 6.2 tons (~13,600 lb), JWST was almost half as heavy at liftoff as NASA’s iconic Hubble Space Telescope despite packing an unprecedented origami-like mirror with more than six times Hubble’s total collecting area. The combination of extreme mass reduction and extraordinary complexity required to launch such a large mirror so far from Earth with a rocket like Ariane 5 helps to partially explain why the Webb Telescope took so long (~18 years) and cost so much (~$9.7 billion) to design, develop, and build.

Nonetheless, launch it finally did. Ariane 5 did most of the work, sending the telescope on a trajectory that – with some help from its onboard thrusters – would guide it to the Sun-Earth L2 Lagrange point located some 1.5 million kilometers (~950,000 miles) from Earth. In perhaps the largest relief in the history of space-based observatories, the Webb Telescope’s immensely complex deployment process was then completed without a single major issue. 30 days after liftoff, the telescope – fully deployed – reached its operational orbit.

For the past four months, in comparison, almost all JWST work has focused on the less visible and far smaller processes of alignment and calibration. Each of JWST’s 18 main mirror segments has slowly but surely inched micrometer by micrometer into position while large swaths of the telescope slowly cooled to ambient temperatures – essential for maximum performance. Simultaneously, all of Webb’s primary instruments have achieved first light and entered the early phases of calibration and commissioning. Only after the instruments are painstakingly calibrated, the mirror is perfectly aligned, and crucial hardware is chilled to temperatures as low as -449°F (-267°C) can Webb begin to observe the universe and revolutionize large subsets of space science.

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An inward view of the fruits of alignment. (NASA)

The first and most important step – mirror alignment – is now complete. The alignment process began in February 2022, six weeks after liftoff. First, images were captured with the unaligned mirror to help determine exactly what condition it was in. One by one, each of Webb’s 18 mirror segments were individually moved to determine which image each mirror was responsible for, which then allowed ground controllers to properly focus each mirror’s view of a target star. In a process known as “coarse phasing,” once those 18 points of light well-resolved and linked to a specific mirror segment, the segments were gradually steered on top of each other to produce a single image.

“Coarse” heavily undersells the almost unfathomable precision required to complete the step. To reach its full potential, each of the Webb Telescope’s mirror segments must be aligned to within 50 nanometers of each other. According to NASA, “if the Webb primary mirror were the size of the United States, each segment would be the size of Texas, and the team would need to line the height of those Texas-sized segments up with each other to an accuracy of about 1.5 inches.”

The product of coarse phasing – beautiful but not yet scientifically useful. (NASA)

Fine phasing followed, involving an even more esoteric set of processes designed to focus the mirror as perfectly as possible. The resulting image was then tweaked to properly align it over the field of view of each of the Webb Telescope’s four main scientific instruments. Finally, some steps of the seven-step alignment process were redone or refined to fully optimize the mirror to the liking of its Earthbound creators and prospective users.

Ultimately, Webb Telescope alignment was extraordinarily successful, producing an image sharper and cleaner than even the “most optimistic predictions” made by its engineers. NASA says that the image is so detailed that it has effectively reached the physical resolution limit for a mirror the size of the Webb Telescope’s, meaning that it would have to violate the known laws of physics to resolve any more detail.

https://twitter.com/AndrasGaspar/status/1520184730985148418
JWST’s first images with a fully aligned mirror. (NASA)

With mirror alignment complete, JWST has just one main hurdle left before science operations can begin: instrument commissioning. Commissioning is a catch-all phrase that covers a wide range of calibration, analysis, experiments, and optimization required to verify that JWST’s four main instruments are behaving as expected and accomplishing the work they were designed to do as accurately and reliably as possible.

At some point, the use of extraordinarily complex scientific instruments becomes more akin to an art form, and some degree of trust must be built up between scientists and their hopeful tools of the trade before they can confidently set chisel to marble and begin delving into the universe at unprecedented breadth and detail. If commissioning proceeds as smoothly as deployment and alignment, the JWST team could be ready to capture and share the telescope’s first actionable observations of the cosmos as early as July 2022.

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Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

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Elon Musk

Tesla Full Self-Driving set to get an awesome new feature, Elon Musk says

Published

12 hours ago

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February 21, 2026

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Credit: Teslarati

Tesla Full Self-Driving is set to get an awesome new feature in the near future, CEO Elon Musk confirmed on X.

Full Self-Driving is the company’s semi-autonomous driving program, which is among the best available to the general public. It still relies on the driver to ultimately remain in control and pay attention, but it truly does make traveling less stressful and easier.

However, Tesla still continuously refines the software through Over-the-Air updates, which are meant to resolve shortcomings in the performance of the FSD suite. Generally, Tesla does a great job of this, but some updates are definitely regressions, at least with some of the features.

Tesla Cybertruck owner credits FSD for saving life after freeway medical emergency

Tesla and Musk are always trying to improve the suite’s performance by fixing features that are presently available, but they also try to add new things that would be beneficial to owners. One of those things, which is coming soon, is giving the driver the ability to prompt FSD with voice demands.

For example, asking the car to park close to the front door of your destination, or further away in an empty portion of the parking lot, would be an extremely beneficial feature. Adjusting navigation is possible through Grok integration, but it is not always effective.

Musk confirmed that voice prompts for FSD would be possible:

Tesla Full Self-Driving is a really great thing, but it definitely has its shortcomings. Navigation is among the biggest complaints that owners have, and it is easily my biggest frustration with using it. Some of the routes it chooses to take are truly mind-boggling.

Another thing it has had issues with is being situated in the correct lane at confusing intersections or even managing to properly navigate through local traffic signs. For example, in Pennsylvania, there are a lot of stop signs with “Except Right Turn” signs directly under.

This gives those turning right at a stop sign the opportunity to travel through it. FSD has had issues with this on several occasions.

Parking preferences would be highly beneficial and something that could be resolved with this voice prompt program. Grocery stores are full of carts not taken back by customers, and many people choose to park far away. Advising FSD of this preference would be a great advantage to owners.

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Cybertruck

Elon Musk clarifies Tesla Cybertruck ’10 day’ comment, fans respond

Some are arguing that the decision to confirm a price hike in ten days is sort of counterproductive, especially considering it is based on demand. Giving consumers a timeline of just ten days to make a big purchase like a pickup truck for $60,000, and basically stating the price will go up, will only push people to make a reservation.

Published

14 hours ago

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February 21, 2026

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Credit: Tesla

Elon Musk has clarified what he meant by his comment on X yesterday that seemed to indicate that Tesla would either do away with the new All-Wheel-Drive configuration of the Cybertruck or adjust the price.

The response was cryptic as nobody truly knew what Musk’s plans were for the newest Tesla Cybertruck trim level. We now have that answer, and fans of the company are responding in a polarizing fashion.

On Thursday night, Tesla launched the Cybertruck All-Wheel-Drive, priced competitively at $59,990. It was a vast improvement from the Rear-Wheel-Drive configuration Tesla launched last year at a similar price point, which was eventually cancelled just a few months later due to low demand.

Tesla launches new Cybertruck trim with more features than ever for a low price

However, Musk said early on Friday, “just for 10 days,” the truck would either be available or priced at $59,990. We can now confirm Tesla will adjust the price based on more recent comments from the CEO.

Musk said the price will fluctuate, but it “depends on how much demand we see at this price level.”

Some are defending the decision, stating that it is simply logical to see how the Cybertruck sells at this price and adjust accordingly.

Others, not so much.

Some are arguing that the decision to confirm a price hike in ten days is sort of counterproductive, especially considering it is based on demand. Giving consumers a timeline of just ten days to make a big purchase like a pickup truck for $60,000, and basically stating the price will go up, will only push people to make a reservation.

Demand will look strong because people want to lock in this price. The price will inevitably go up, and demand for the trim will likely fall a bit because of the increased cost.

Many are arguing Musk should have kept this detail internal, but transparency is a good policy to have. It is a polarizing move to confirm a price increase in just a week-and-a-half, but the community is obviously split on how to feel.

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Cybertruck

Tesla Cybertruck’s newest trim will undergo massive change in ten days, Musk says

It appears as if the new All-Wheel-Drive trim of Cybertruck won’t be around for too long, however. Elon Musk revealed this morning that it will be around “only for the next 10 days.”

Published

2 days ago

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February 20, 2026

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(Credit: Tesla)

Tesla’s new Cybertruck trim has already gotten the axe from CEO Elon Musk, who said the All-Wheel-Drive configuration of the all-electric pickup will only be available “for the next ten days.”

Musk could mean the price, which is $59,990, or the availability of the trim altogether.

Last night, Tesla launched the All-Wheel-Drive configuration of the Cybertruck, a pickup that comes in at less than $60,000 and features a competitive range and features that are not far off from the offerings of the premium trim.

Tesla launches new Cybertruck trim with more features than ever for a low price

It was a nice surprise from Tesla, considering that last year, it offered a Rear-Wheel-Drive trim of the Cybertruck that only lasted a few months. It had extremely underwhelming demand because it was only $10,000 cheaper than the next trim level up, and it was missing a significant number of premium features.

Simply put, it was not worth the money. Tesla killed the RWD Cybertruck just a few months after offering it.

With the news that Tesla was offering this All-Wheel-Drive configuration of the Cybertruck, many fans and consumers were encouraged. The Cybertruck has been an underwhelming seller, and this seemed to be a lot of truck for the price when looking at its features:

  • Dual Motor AWD w/ est. 325 mi of range
  • Powered tonneau cover
  • Bed outlets (2x 120V + 1x 240V) & Powershare capability
  • Coil springs w/ adaptive damping
  • Heated first-row seats w/ textile material that is easy to clean
  • Steer-by-wire & Four Wheel Steering
  • 6’ x 4’ composite bed
  • Towing capacity of up to 7,500 lbs
  • Powered frunk

It appears as if this trim of Cybertruck won’t be around for too long, however. Musk revealed this morning that it will be around “only for the next 10 days.”

Musk could mean the price of the truck and not necessarily the ability to order it. However, most are taking it as a cancellation.

If it is, in fact, a short-term availability decision, it is baffling, especially as Tesla fans and analysts claim that metrics like quarterly deliveries are no longer important. This seems like a way to boost sales short-term, and if so many people are encouraged about this offering, why would it be kept around for such a short period of time?

Some are even considering the potential that Tesla axes the Cybertruck program as a whole. Although Musk said during the recent Q4 Earnings Call that Cybertruck would still be produced, the end of the Model S and Model X programs indicates Tesla might be prepared to do away with any low-volume vehicles that do not contribute to the company’s future visions of autonomy.

The decision to axe the car just ten days after making it available seems like a true head-scratcher.

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