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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 dispels reports of ‘sales suspension’ in California

“This was a “consumer protection” order about the use of the term “Autopilot” in a case where not one single customer came forward to say there’s a problem.

Sales in California will continue uninterrupted.”

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Credit: Tesla

Tesla has dispelled reports that it is facing a thirty-day sales suspension in California after the state’s Department of Motor Vehicles (DMV) issued a penalty to the company after a judge ruled it “misled consumers about its driver-assistance technology.”

On Tuesday, Bloomberg reported that the California DMV was planning to adopt the penalty but decided to put it on ice for ninety days, giving Tesla an opportunity to “come into compliance.”

Tesla enters interesting situation with Full Self-Driving in California

Tesla responded to the report on Tuesday evening, after it came out, stating that this was a “consumer protection” order that was brought up over its use of the term “Autopilot.”

The company said “not one single customer came forward to say there’s a problem,” yet a judge and the DMV determined it was, so they want to apply the penalty if Tesla doesn’t oblige.

However, Tesla said that its sales operations in California “will continue uninterrupted.”

It confirmed this in an X post on Tuesday night:

The report and the decision by the DMV and Judge involved sparked outrage from the Tesla community, who stated that it should do its best to get out of California.

One X post said California “didn’t deserve” what Tesla had done for it in terms of employment, engineering, and innovation.

Tesla has used Autopilot and Full Self-Driving for years, but it did add the term “(Supervised)” to the end of the FSD suite earlier this year, potentially aiming to protect itself from instances like this one.

This is the first primary dispute over the terminology of Full Self-Driving, but it has undergone some scrutiny at the federal level, as some government officials have claimed the suite has “deceptive” naming. Previous Transportation Secretary Pete Buttigieg was vocally critical of the use of the name “Full Self-Driving,” as well as “Autopilot.”

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New EV tax credit rule could impact many EV buyers

We confirmed with a Tesla Sales Advisor that any current orders that have the $7,500 tax credit applied to them must be completed by December 31, meaning delivery must take place by that date. However, it is unclear at this point whether someone could still claim the credit when filing their tax returns for 2025 as long as the order reflects an order date before September 30.

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tesla showroom
Credit: Tesla

Tesla owners could be impacted by a new EV tax credit rule, which seems to be a new hoop to jump through for those who benefited from the “extension,” which allowed orderers to take delivery after the loss of the $7,500 discount.

After the Trump Administration initiated the phase-out of the $7,500 EV tax credit, many were happy to see the rules had been changed slightly, as deliveries could occur after the September 30 cutoff as long as orders were placed before the end of that month.

However, there appears to be a new threshold that EV buyers will have to go through, and it will impact their ability to get the credit, at least at the Point of Sale, for now.

Delivery must be completed by the end of the year, and buyers must take possession of the car by December 31, 2025, or they will lose the tax credit. The U.S. government will be closing the tax credit portal, which allows people to claim the credit at the Point of Sale.

We confirmed with a Tesla Sales Advisor that any current orders that have the $7,500 tax credit applied to them must be completed by December 31, meaning delivery must take place by that date.

However, it is unclear at this point whether someone could still claim the credit when filing their tax returns for 2025 as long as the order reflects an order date before September 30.

If not, the order can still go through, but the buyer will not be able to claim the tax credit, meaning they will pay full price for the vehicle.

This puts some buyers in a strange limbo, especially if they placed an order for the Model Y Performance. Some deliveries have already taken place, and some are scheduled before the end of the month, but many others are not expecting deliveries until January.

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Elon Musk takes latest barb at Bill Gates over Tesla short position

Bill Gates placed a massive short bet against Tesla of ~1% of our total shares, which might have cost him over $10B by now

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Elon Musk took his latest barb at former Microsoft CEO Bill Gates over his short position against the company, which the two have had some tensions over for a number of years.

Gates admitted to Musk several years ago through a text message that he still held a short position against his sustainable car and energy company. Ironically, Gates had contacted Musk to explore philanthropic opportunities.

Elon Musk explains Bill Gates beef: He ‘placed a massive bet on Tesla dying’

Musk said he could not take the request seriously, especially as Gates was hoping to make money on the downfall of the one company taking EVs seriously.

The Tesla frontman has continued to take shots at Gates over the years from time to time, but the latest comment came as Musk’s net worth swelled to over $600 billion. He became the first person ever to reach that threshold earlier this week, when Tesla shares increased due to Robotaxi testing without any occupants.

Musk refreshed everyone’s memory with the recent post, stating that if Gates still has his short position against Tesla, he would have lost over $10 billion by now:

Just a month ago, in mid-November, Musk issued his final warning to Gates over the short position, speculating whether the former Microsoft frontman had still held the bet against Tesla.

“If Gates hasn’t fully closed out the crazy short position he has held against Tesla for ~8 years, he had better do so soon,” Musk said. This came in response to The Gates Foundation dumping 65 percent of its Microsoft position.

Tesla CEO Elon Musk sends final warning to Bill Gates over short position

Musk’s involvement in the U.S. government also drew criticism from Gates, as he said that the reductions proposed by DOGE against U.S.A.I.D. were “stunning” and could cause “millions of additional deaths of kids.”

“Gates is a huge liar,” Musk responded.

It is not known whether Gates still holds his Tesla short position.

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