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SpaceX CEO Elon Musk explains how Starships will return from orbit

SpaceX's Starship spacecraft will eventually have to survive orbital-velocity reentries, a spectacularly difficult feat for large spacecraft. (NASASpaceflight - bocachicagal)

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In the near future, SpaceX wants to begin putting its first two full-scale Starship prototypes through a series of increasingly challenging test flights, eventually culminating in their first Super Heavy-supported orbital launch attempts.

SpaceX CEO Elon Musk took to Twitter over the last 48 or so hours to answer a number of questions about how exactly Starship is meant to make it through orbital reentries – by far the most strenuous period for the ship and without a doubt the single most challenging engineering problem SpaceX must tackle.

Starship glows from heating as it reenters Earth’s atmosphere in this official render. (SpaceX)

Discussed yesterday on Teslarati, SpaceX technicians began the process of attaching numerous Tesla Model S/X battery packs to a subcomponent that will eventually be installed inside Starship Mk1’s nose, offering a storage capacity of up to 400 kWh. The need for all that power (Crew Dragon relies on a few-kWh battery) is directly related to Starship Mk1’s methods of reentry and recovery, recently described in detail by Elon Musk.

As noted above, ~400 kWh of batteries are needed to power the electric motors that will actuate Starship’s massive control surfaces – two large aft wings and two forward canards/fins. According to Musk, Starship’s “stability is controlled by (very) rapid movement of rear & fwd fins during entry & landing”, meaning that the spacecraft will need to constantly tweak its control surfaces to remain in stable flight.

This official graphic covers Starship’s exotic method of flight and landing. (SpaceX)

By far the biggest challenge SpaceX faces is ensuring that Starship can survive numerous orbital-velocity reentries with little to no wear and tear, a necessity for Starship to be cost-effective. In Low Earth Orbit (LEO), Starship will be traveling no less than 7.8 km/s (Mach 23, 17,500 mph) at the start of atmospheric reentry. In simple terms, the process of slowing from orbital velocity to landing on Earth involves turning the vast majority of that kinetic energy into heat. As Musk noted yesterday, this reality is just shy of unavoidable but there is some flexibility in terms of how quickly one wants to convert that energy into heat.

The fastest route to Earth would involve diving straight into the atmosphere, dramatically increasing peak heating on a spacecraft’s surface to the point that extremely exotic heat shields and thermal protections systems become an absolute necessity. SpaceX wants to find a middle ground with Starship in which the spacecraft uses its aerodynamic control surfaces and body to generate lift, slowly and carefully lowering itself into Earth’s atmosphere over a period of 15+ minutes. Musk notes that this dramatically lessens peak heating at the cost of increasing the overall amount of energy Starship has to dissipate, a bit like cooking something in the oven at 300 degrees for 30 minutes instead of 600 degrees for 10 minutes.

To an extent, Starship’s reentry profile is actually quite similar to NASA’s now-retired Space Shuttle, which took approximately 30 minutes to go from its reentry burn to touchdown. Per the above infographic, it looks like Starship will take approximately 20 minutes from orbit to touchdown, owing to a dramatically different approach once it reaches slower speeds. Originally described by Musk in September 2018 and again in recent weeks, Starship will essentially stall itself until its forward velocity is nearly zero, after which the giant spacecraft will fall belly-down towards the Earth, using its wings and fins to maneuver like a skydiver. The Space Shuttle landed on a runway like a (cement-encased) glider.

This unusual approach allows SpaceX to sidestep the need for huge wings, preventing Starship from wasting far more mass on aerodynamic surfaces it will rarely need. The Space Shuttle is famous for its massive, tile-covered delta wing and the leading-edge shielding that partially contributed to the Columbia disaster. However, it’s a little-known fact that the wing’s size and shape were almost entirely attributable to US Air Force demands for cross-range performance, meaning that the military wanted Shuttles to be able to travel 1000+ miles during reentry and flight. This dramatically constrained the Shuttle’s design and was never once used for its intended purpose.

Space Shuttle Endeavor shows off its main heat shield during an on-orbit inspection in August 2007. (NASA)

SpaceX thankfully doesn’t have its own “US Air Force” stand-in making highly consequential demands (aside from Elon Musk ?). Instead, Starship will continue the SpaceX tradition of vertical landing, falling straight down – a bit like a skydiver (or a brick) – on its belly and flipping itself over with fins and thrusters for a propulsive vertical landing. In this way, Starship doesn’t have to be a brick forced to fly, like the Shuttle was – it just needs to be able to stably fall and quickly flip itself from a horizontal to vertical orientation.

Additionally, Starship is built almost entirely out of steel, whereas the Shuttle relied on an aluminum alloy and needed thermal protection over every square inch of its hull. Steel melts at nearly twice the temperature of the Shuttle’s alloy, meaning that Starship will (hopefully) be able to get away with nothing more than ceramic tiles on its windward half, saving mass, money, and time. Once Starship completes its first 20 km (12.5 mi) flight test(s), currently scheduled no earlier than mid-October, SpaceX will likely turn its focus on verifying Starship’s performance at hypersonic speeds, ultimately culminating in its first orbital-velocity reentries.

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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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Tesla Cybercab ‘breakdown’ image likely is not what it seems

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Credit: TslaChan | X

Tesla Cybercab is perhaps the most highly-anticipated project that the company plans to roll out this year, and as it is undergoing its testing phase in pre-production currently, there are some things to work through with it.

Over the weekend, an image of the Cybercab being loaded onto a tow truck started circulating on the internet, and people began to speculate as to what the issue could be.

The Cybercab can clearly be seen with a Police Officer and perhaps the tow truck driver by its side, being loaded onto, or even potentially unloaded from, the truck.

However, it seems unlikely it was being offloaded, as its operation would get it to this point for testing to begin with.

It appears, at first glance, that it needs assistance getting back to wherever it came from; likely Gigafactory Texas or potentially a Bay Area facility.

The Cybercab was also spotted in Buffalo, New York, last week, potentially undergoing cold-weather testing, but it doesn’t appear that’s where this incident took place.

It is important to remember that the Cybercab is currently undergoing some rigorous testing scenarios, which include range tests and routine public road operation. These things help Tesla assess any potential issue the vehicle could run into after it starts routine production and heads to customers, or for the Robotaxi platform operation.

This is not a one-off issue, either. Tesla had some instances with the Semi where it was seen broken down on the side of a highway three years ago. The all-electric Semi has gone on to be successful in its early pilot program, as companies like Frito-Lay and PepsiCo. have had very positive remarks.

Tesla reveals its first Semi customer after launch

The Cybercab’s future is bright, and it is important to note that no vehicle model has ever gone its full life without a breakdown. It happens, it’s a car.

Nevertheless, it is important to note that there has been no official word on what happened with this particular Cybercab unit, but it is crucial to remember that this is the pre-production testing phase, and these things are more constructive than anything.

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Investor's Corner

Tesla analyst teases self-driving dominance in new note: ‘It’s not even close’

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Credit: Tesla

Tesla analyst Andrew Percoco of Morgan Stanley teased the company’s dominance in its self-driving initiative, stating that its lead over competitors is “not even close.”

Percoco recently overtook coverage of Tesla stock from Adam Jonas, who had covered the company at Morgan Stanley for years. Percoco is handling Tesla now that Jonas is covering embodied AI stocks and no longer automotive.

His first move after grabbing coverage was to adjust the price target from $410 to $425, as well as the rating from ‘Overweight’ to ‘Equal Weight.’

Percoco’s new note regarding Tesla highlights the company’s extensive lead in self-driving and autonomy projects, something that it has plenty of competition in, but has established its prowess over the past few years.

He writes:

“It’s not even close. Tesla continues to lead in autonomous driving, even as Nvidia rolls out new technology aimed at helping other automakers build driverless systems.”

Percoco’s main point regarding Tesla’s advantage is the company’s ability to collect large amounts of training data through its massive fleet, as millions of cars are driving throughout the world and gathering millions of miles of vehicle behavior on the road.

This is the main point that Percoco makes regarding Tesla’s lead in the entire autonomy sector: data is King, and Tesla has the most of it.

One big story that has hit the news over the past week is that of NVIDIA and its own self-driving suite, called Alpamayo. NVIDIA launched this open-source AI program last week, but it differs from Tesla’s in a significant fashion, especially from a hardware perspective, as it plans to use a combination of LiDAR, Radar, and Vision (Cameras) to operate.

Percoco said that NVIDIA’s announcement does not impact Morgan Stanley’s long-term opinions on Tesla and its strength or prowess in self-driving.

NVIDIA CEO Jensen Huang commends Tesla’s Elon Musk for early belief

And, for what it’s worth, NVIDIA CEO Jensen Huang even said some remarkable things about Tesla following the launch of Alpamayo:

“I think the Tesla stack is the most advanced autonomous vehicle stack in the world. I’m fairly certain they were already using end-to-end AI. Whether their AI did reasoning or not is somewhat secondary to that first part.”

Percoco reiterated both the $425 price target and the ‘Equal Weight’ rating on Tesla shares.

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Elon Musk

Donald Trump turns to Elon Musk and Starlink amid Iran internet blackout

Donald Trump has stated that he plans to speak with SpaceX CEO Elon Musk about restoring internet access in Iran.

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Credit: Starlink/X

Donald Trump has stated that he plans to speak with SpaceX CEO Elon Musk about restoring internet access in Iran, as authorities in the country implement an internet blackout amid nationwide anti-government protests. 

Trump points to Starlink

Speaking to reporters in Washington, Trump said Musk would be well-suited to help restore connectivity in Iran, citing his experience operating large-scale satellite networks, as noted in a Reuters report. “He’s very good at that kind of thing, he’s got a very good company,” Trump said. 

Iran has experienced a near-total internet shutdown for several days, severely limiting the flow of information as protests escalated into broader demonstrations against the country’s rulers.

Starlink has previously been used in Iran during periods of unrest, allowing some users to access the global internet despite government blocks. Neither Musk nor SpaceX immediately commented on Trump’s remarks, but Musk has publicly supported efforts to provide Starlink access to Iranians during earlier periods of unrest.

Renewed Trump–Musk ties

Trump’s comments come amid a thaw in his previously strained relationship with Musk. The two had a public falling-out last year over domestic policy disagreements but have since appeared together publicly, including at Trump’s Mar-a-Lago resort. The renewed ties now intersect with foreign policy, as Starlink has become a strategic tool in regions facing censorship or conflict.

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The satellite service has also played a prominent role elsewhere, most notably in Ukraine, highlighting both its potential impact and the political sensitivities surrounding its use. In Iran, Starlink support previously followed coordination between Musk and U.S. officials during protests in 2022.

The current internet blackout in Iran has drawn international attention, with rights groups estimating hundreds of deaths and thousands of arrests since demonstrations intensified late last year. Iranian authorities have not released official casualty figures, and outside verification remains limited due to restricted communications.

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