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

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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.

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.”

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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.

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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Tesla says it denied Musk CEO replacement report before it was published

Tesla says it responded to the WSJ’s request for comment, denying that it was in search of a new CEO to replace Elon Musk.

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(Credit: Tesla)

Tesla said that it denied seeking a replacement for CEO Elon Musk before a report was published claiming the company was considering a new frontman.

Last night, The Wall Street Journal reported that Tesla’s Board of Directors was looking for Musk’s replacement after he had devoted too much time to his role within the government. The publication revised its headline to the report no fewer than five times, initially stating the company was still seeking a replacement.

By the time the headline revisions were complete, it had outlined that Tesla had looked for a replacement a month ago, but had stopped its search following Musk’s commitment to Tesla during the company’s earnings call last month.

Shortly after the report surfaced, Board of Directors chairwoman Robyn Denholm officially issued a statement on behalf of Tesla:

“Earlier today, there was a media report erroneously claiming that the Tesla Board had contacted recruitment firms to initiate a CEO search at the company. This is absolutely false (and this was communicated to the media before the report was published). The CEO of Tesla is Elon Musk and the Board is highly confident in his ability to continue executing on the exciting growth plan ahead.  – Robyn Denholm.”

Tesla Board Chair slams Wall Street Journal over alleged CEO search report

Interestingly, Denholm’s statement indicates it had responded to a request for comment from the Wall Street Journal before the report was published. This is especially interesting because Tesla does not typically respond to media outreach, as it dissolved its media department several years ago.

Tesla typically makes its statements publicly on X.

Musk also responded to the report, indicating that the WSJ had committed an “extremely bad breach of ethics” by publishing a “deliberately false article” that did not include Tesla’s “unequivocal denial beforehand.”

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Robotaxis are already making roads safer, Waymo report reveals

Waymo Driver is already reducing severe crashes and enhancing the safety of vulnerable road users.

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Waymo hires former Tesla Executive 
(Credit: Waymo)

Industry leaders such as Elon Musk have always maintained that autonomous robotaxis will make roads safer. A recent blog post from Waymo about the safety of its self-driving cars suggests that Musk’s sentiments are on point.

Way More Safety

Waymo Driver is already reducing severe crashes and enhancing the safety of vulnerable road users. As per a new research paper set for publication in the Traffic Injury Prevention Journal, Waymo Driver had outperformed human drivers in safety, particularly for vulnerable road users (VRUs).

Over 56.7 million miles, compared to human drivers, Waymo Driver achieved a 92% reduction in pedestrian injury crashes. It also saw 82% fewer crashes with injuries with cyclists and 82% fewer crashes with injuries with motorcyclists. Waymo Driver also slashed injury-involving intersection crashes by 96%, which are a leading cause of severe road harm for human drivers. Waymo Driver saw 85% fewer crashes with suspected serious or worse injuries as well.

What They Are Saying

Mauricio Peña, Waymo’s Chief Safety Officer, was optimistic about Waymo Driver’s results so far. “It’s exciting to see the real positive impact that Waymo is making on the streets of America as we continue to expand. This research reinforces the growing evidence that the Waymo Driver is playing a crucial role in reducing serious crashes and protecting all road users,” the Chief Safety Officer noted.

Jonathan Adkins, Chief Executive Officer at Governors Highway Safety Association, also noted that Waymo’s results are very encouraging. “It’s encouraging to see real-world data showing Waymo outperforming human drivers when it comes to safety. Fewer crashes and fewer injuries — especially for people walking and biking — is exactly the kind of progress we want to see from autonomous vehicles,” Adkins stated.

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Tesla hints at June 1 launch of Robotaxi platform in Austin

Tesla has hinted at a potential launch date for the Robotaxi service in Austin, Texas.

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tesla robotaxi app on phone
Credit: Tesla

Tesla just dropped its biggest hint yet about the potential launch date of its Robotaxi ride-hailing platform in Austin, Texas, shedding more light on when to expect it to take off.

In preparation for the ride-hailing service to launch, Tesla has been in talks with the City of Austin for months. It has also spent recent months bolstering its Full Self-Driving suite, aiming for it to handle initially supervised rides with the use of teleoperators to keep things safe and dependable, at least early on.

The company has also said that it expects the Robotaxi service, which will drive passengers in Tesla Model Y vehicles to start, to launch in Austin in June. However, Tesla has not given an exact date.

Now, Tesla is hinting that Robotaxi could launch on June 1, based on a very vague X post it published on May 1:

Of course, this is extremely speculative. However, it’s the first time Tesla has made any suggestions about a potential launch date, so it’s worth taking it seriously.

While the automaker has often missed timelines in the past, most notably the launch of a “feature-complete” Full Self-Driving platform, this is the first time we’ve seen Tesla be so adamant and truly reiterate a target date.

Tesla has not shied away from this June date for the Robotaxi launch yet, something that is worth noting as we move closer to June. All signs point toward Tesla being able to come through on this timeline, and it could be one of its biggest accomplishments yet on the grand scheme of things. The Robotaxi rollout will be controlled and small to start, the company noted on its most recent Earnings Call.

CEO Elon Musk said:

“The team and I are laser-focused on bringing robotaxi to Austin in June. Unsupervised autonomy will first be solved for the Model Y in Austin.”

At first, it also seems as if the first Robotaxi rides will be available to a select group, as Musk said the ability to order one will not be available to the general public until later in the month. He also said the initial fleet will be between 10 and 20 vehicles:

“Yeah. We’re still debating the exact number to start off on day one, but it’s, like, I don’t know, maybe 10 or 20 vehicles on day one. And watch it carefully. They scale it up rapidly after that. So, we want to make sure that you’re paying very close attention the first time this happens. But, yeah, you will be able to — end of end of June or July, just go to Austin and order a Tesla for autonomous drive.”

While the June 1st date of the Robotaxi launch is extremely speculative, Tesla seems convinced that its vehicles could already handle this task. It would be something to see them come through on this date, especially on the first day of the month.

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